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I would like some advice from members on the topic of blocking the bass ports on nearfield speakers.

I have a set of KRK Rokit 5 Gen2 (I know, I know, before you get started they were cheap and I was on a budget at the time and have'nt upgraded yet) pictured below, which have a front bass port below the driver at the front.
Although the pic does not show it, I have them sitting on neoprene mouse pads to isolate them from my desk, I do plan to pick up some speaker feet early next week to replace said el cheapo isolation option.

These are situated around 6 inches from the wall behind and I have acoustic tiles which are 2 inches thick behind said monitors.

I have read differing opinions on whether or not blocking the bass ports is a good idea, bad idea, better /worse, so I experimented with a piece of high density memory foam cut and placed into the front port to see if I could hear any difference.

To my ears the difference is very minimal, but I would like to know the following from those in the know:-

a) does it tighten up the bass sound ?

b) Does it effect the driver response by restricting the air pressure / flow thereby limiting the driver travel or slew the response?

c) Would using something like the HD memory foam I have used allow air pressure to escape as opposed to something more solid such as, dare I say it, styrofoam?

c) What effect would this have on say EQ and the overall sound / how it translates?

d) Any other thoughts or considerations I would need to take into account?

Thanks in advance for any advice on the matter.

Edit - I am not running a subwoofer with these as the room is not that large (11ft x 15ft)

Attached files

Comments

pcrecord Sun, 09/13/2015 - 05:10

I'm gonna follow this thread to read what others think about it.
Here is my guess : Yes, it will change the frequency response of the speaker but making the bass thighter would be a complete 1 to a million chances.
Most of what will happen is unbalance it and make things worst. A small piece of foam would more affect low mids than bass...
Usually bass ports are there to recover some sound pressure created by the speaker to produce bass frequencies otherwise not present in the box.

In my opinion, messing with it won't correct room accoustic problems and won't make a 100$ speaker sound like a 1000$.

Sean G Sun, 09/13/2015 - 05:35

Thanks for your reply pcrecord

In my opinion, messing with it won't correct room accoustic problems and won't make a 100$ speaker sound like a 1000$.

I'm not looking to fix room acoustic problems, (the room for what it is has some acoustic treatment at first points of reflection, main walls at strategic spots and some bass trapping & a carpeted floor) or make them sound like $1000 monitors, just wanting to know if it does or does not improve the overall sound of these budget boxes.

The plan is to upgrade shortly to maybe something like a hs-10 or JBL LS 305P ???, there is a store here in Sydney where you can try out many different sets before you buy, but that does not give you any idea how they sound in your room environment or through your set up

I have even read of the "old bundle of straws in the bass port trick", I can't say Iv'e tried that one.

DonnyThompson Sun, 09/13/2015 - 05:40

I've done this occasionally, but only in situations where the monitors were located in close proximity to walls and/or control room windows; and as Marco mentioned, it's only ever going to be so effective; the larger determining factor is the room in which you are monitoring, and you won't be able to correct that without actually treating the space.

You might be able to compensate a little bit; if perhaps you are in a space where you have little to no choice about where the monitors are located, and if they are if close proximity to corners or boundaries, and are perhaps creating standing waves because of their location and placement... but you also need to keep in mind that by doing this, you could also be over-compensating too, and perhaps even skewing the monitors for the worse... ending up very far away from their original response/tuning, to the point that other frequencies would also be affected - and they could very well end up being frequencies you might not want to change.

By plugging the ports, for better or worse, you are changing the way the speakers were designed and intended to be used, and how they were measured in regard to frequency response.

The only thing you can do is to try it, and then listen to how the mixes sound on other systems, to see how well they translate outside of your mixing space.

FWIW

DonnyThompson Sun, 09/13/2015 - 05:51

As a follow up Sean -
I'd personally place a lot more importance on the acoustics of the space over the types of monitors. Put it this way - If given a choice, I'd rather use a pair of "okay" Alesis Monitor Ones in a treated space, than I would a pair of "boutique" Genelecs in an untreated space.

Now, there have been recent advancements made in room modeling and software compensation, that will allow monitors to be tuned to rooms via artificial modeling processing; and at the rate that Modeling Technology is moving these days, I wouldn't be surprised if at some point, someone comes up with an acoustic modeling program that actually works; something that will allow for accurate frequency compensation in monitors of all types... but I don' think that these companies are there quite yet; so for now, you'll be better off to look into treating the space you are in. as opposed to messing with the original physical design of the monitors you are using.

Out of curiosity, what monitors are you using?

Sean G Sun, 09/13/2015 - 05:52

Thanks for the advice Donny.
Monitor placement is situated in the centre of one of the longer 15 ft walls, with monitors around 2 to 4 inches from the wall.
I have placed some acoustic tiles 2 inches thick behind the monitors, allowing for them to rise with the addition of some speaker feet.
I have treated the wall behind my monitoring space with 4 x 20x20 inch x 2 inch thick acoustic tiles directly behind me grouped together in a large square, with 2 more placed centre either side of that between those 4 and the corners. I have treated the corners with some bass traps to help cut down the build up of bass frequencies in the 4 corners of the room but due to the limitations with the size of the room compared to the typical wavelength of bass frequencies I am aware that these are limited to what they can cut down. I have also treated the wall behind my desk and above my LCD screen.
There's also a really heavy 2 seat fabric sofa with a fold out sofa bed inside it directly behind me along that other long wall below those 4 tiles grouped together to help break up the reflection. But as always, I can only work with the environment until circumstance allows me to move up and try to improve things where I can.
Edit : First points of reflection are treated and so too is the rear of the solid timber door.

DonnyThompson Sun, 09/13/2015 - 06:46

Sean G, post: 432372, member: 49362 wrote: with monitors around 2 to 4 inches from the wall.

That's a factor right there, Sean. If you are hearing too much low end, or, are hearing low end as "undefined" of "frumpy" (loose), this would be one of the reasons why.

Sean G, post: 432372, member: 49362 wrote: I have placed some acoustic tiles 2 inches thick behind the monitors, allowing for them to rise with the addition of some speaker feet.

Depending on the type of material these tiles are made of, that probably isn't thick enough to handle the frequencies you are having problems with. If you are using something similar to Auralex, 2" will only be effective down to around 500hz or so. It won't attenuate the low frequencies; those that are down around 200hz... and lower.

When you place a monitor in close proximity to a boundary ( walls, ceilings, floors) some of those various low-frequency and frequency ranges will emanate from the rear of the monitor, and will reflect off of these boundaries.

Depending on what the distance is, some frequencies will bounce back in phase, resulting in peaks in that frequency range, while others might come back out of phase, and could end up cancelling out certain frequencies, which then ends up giving you "nulls", which can really play havoc with your ears - because what you are hearing isn't what is really going on.

The short of it is, your ears are being lied to by the frequency response of the room, along with the sound coming out of your monitors in that room.

Try walking around your room while music is playing, and listen for "hot spots" as well as for "nulls". Hot spots will reveal themselves as a "jump" in level for a certain frequency or range, while nulls will sound much lower in volume, and in some cases, these frequencies can even disappear completely.

This is where room treatment can help - through Bass Traps ( corners especially) that will attenuate low end frequencies from a certain point on down ( example, 200hz and lower), BB Absorbers ( broad band) which will attenuate a wider range of frequencies ( example 200hz and higher - depending on the thickness/ mass/density of the material used) - and Diffusion, which is meant to "scatter" frequencies, so that they aren't hitting each other ( and your ears) all at the same time.

You could try plugging the ports on your monitors, but honestly, it probably won't be very effective, and as I mentioned arlier, you could end up with other issues as well. A better, more effective option, and one that is proven because it's largely based on physics and actual calculations - would be to look into room treatment. The good news with room treatment is that it doesn't have to be expensive to be effective. There are many materials available at home improvement stores that are very effective; things like Roxul Safe and Sound, or OC ( Owens Corning) rigid insulation, etc., and because these materials are so light in weight, you don't have to build huge, heavy frames to hold the material in place.

But, you first need to find out what your room is really doing. If it were me, I'd start by measuring the room; there are some good measurement programs available on the web, some even free:

http://www.roomeqwizard.com/

You'll need a measurement microphone... the standard go-to for this is the Earthworks Omni; although it's pricey. Behringer makes an omni-directional measurement mic, the ECM8000; and while I've personally never used it, I have colleagues who have, and with success:

http://www.zzounds.com/item--BEHECM8000

So for a grand total of $59 (U.S.) you could measure your room and get a fairly accurate idea of what is happening. The cost of your treatment could also end up being very affordable... you might even be able to do if for under $100; the more handy you are with building frames and installing the treatment, the more money you'd save.

I guess what I'm suggesting Sean, is that you may very well be able to end up fixing ( or at least greatly improving) your mixing environment for really not all that much money. Not only will this help you with mixing, it could also prove to be advantageous for recording, too.

FWIW, here's an article on monitor placement that you might want to take a look at:

http://www.soundonsound.com/sos/mar02/articles/monitors.asp

Sean G Sun, 09/13/2015 - 07:06

Thanks for the advice, much appreciated.
I have looked at the room EQ wizard after reading another post here on RO, its good advice.
When I get to that point I may post a thread to get some further advice as to how to correctly measure the room going forward.
I shall definitely have a read of the article above also...cheers.

dvdhawk Sun, 09/13/2015 - 07:15

Some questions:

Are you suffering from too much bass as is?
Do they have to sit so close to the wall?
Are they angled inward, or firing straight out?
Are you using any EQ now to add or subtract bass response?
How do your mixes translate to the outside world and other playback systems now?
Have you run any kind of analyzer to identify problem frequencies?

Plugging the port will certainly restrict the movement of the woofer, which would generally produce less low-end on two fronts. (Neither the woofer, nor the port would be moving as much air)
I couldn't say it will 'tighten' the bass response, but I would guess it would reduce it some.
My concern would be that you might over-compensate EQing more lows into everything across the board.

The engineers at KRK calculated the port size and port depth based on how that particular 5" woofer behaves in a ported box with a very specific volume (in terms of cubic cm or inches). But like everyone else, manufacturers can often fall prey to their own hype and sacrifice accuracy for exaggerated bass. And even though it's ported out the front, bass frequencies are still radiating out the back and sides of the box - frequencies probably too low to be very effectively absorbed by foam.

This might even be a case where, even though you say your room isn't very large, a subwoofer might be a better way to tighten up the bass by taking some of the burden off the smallish 5" woofer in the KRKs. There is only so much bass you can get from a 5".

So I don't really have any concrete answers, just more questions to consider moving forward.

Sean G Sun, 09/13/2015 - 07:21

As a side note, I wanted put it on the record how appreciative I am to be part of the RO community, its such a great resource for learning and its a credit to RO members who are openly willing to share their time, knowledge and experience on recording, especially with someone who made the transition from playing to recording late in the game.
A huge thank you from the Land Down Under.(n)(n)(n)

Sean G Sun, 09/13/2015 - 07:51

dvdhawk, post: 432378, member: 36047 wrote: Are you suffering from too much bass as is?
Do they have to sit so close to the wall?
Are they angled inward, or firing straight out?
Are you using any EQ now to add or subtract bass response?
How do your mixes translate to the outside world and other playback systems now?
Have you run any kind of analyzer to identify problem frequencies?

Thanks for your input dvdhawk, there are some good questions there.
I'll see if I can cover them all.
I can't really say I'm suffering from too much bass, I suppose that also comes down to levels set during the tracking process.
Some of the work I have mixed so far also is a collection of tracks that I have recorded over a course of some years in different environments, rooms etc, some treated, some not, that have to date been works in progress so to speak. Not a lot of live tracking in this room to date.
At present, they are close to the wall, probably too close to it for my liking. I am playing with the idea of bringing the desk out from the wall and trying to get my seating position more centred to the room, but not in the centre. Any suggestions on the room size dimensions (11 x 15 ft x 9ft high) you could recommend? - I see from your room build you would be more versed in monitor placement than I would in that department.
As for EQ, so far it has come down to what tracks I have been mixing but I don't appear to be doing too much either way. Listening to my mixes on other systems such as the car, phone + tablet with earbuds, dvd home theatre are translating well although on a couple of tracks the bass was a little harsh, which supprised me somewhat at first because I thought with the room size it may have been the other way around. My headphones I use as a reference are AKG 701s' which can be somewhat biased in the mid / highs so they could be coming into play also, but I try to mix using a balance of both monitors and headphones (HP mostly in the late hours).
I have not used an analyser to look for problem frequencies as such but definately now you have mentioned it, theres' something to look at.
Consideration has been given at a sub, due to thinking about upgrading to a better grade of monitor I have put that on hold for the time being but something worth pondering.
You are spot-on, theres' only so much low end you can get out of a 5 inch driver. If not a sub, maybe even going to an 8 inch monitor may be worth considering also.
I know that these are designed by a team who do their research and put the port there for a very good reason, so I'm probably upsetting the apple cart by blocking the port and changing the way the monitors are supposed to sound.
Having read different pros / cons on the idea of blocking the port, I thought it was worth throwing it out there to see what came back from those in the know.
I suppose doing a mix with them blocked / unblocked may be worth trying also...

Edit : they are approx 26 inches apart, angled towards my seating position, directed at ear level height and I'm in the sweet spot with each monitor 26 inches from each ear.

DonnyThompson Sun, 09/13/2015 - 07:57

dvdhawk, post: 432378, member: 36047 wrote: My concern would be that you might over-compensate EQing more lows into everything across the board.

Ya. I have the same concern(s) Hawk... as well as what might else occur by altering the physical properties of the cabinet - in regard to the way the cabinet was originally designed and tuned for... although I have to be honest and admit that I wasn't aware that the KRK's he has are front-ported...

Sean G, post: 432372, member: 49362 wrote: I have treated the wall behind my monitoring space with 4 x 20x20 inch x 2 inch thick acoustic tiles directly behind me grouped together in a large square, with 2 more placed centre either side of that between those 4 and the corners.

Remember Sean... in regard to room treatment, that the effectiveness of frequency attenuation - and in your case, low frequency attenuation - is determined by the thickness/mass/density of the material being used.
(Side note: There is also the possibility that you can increase the effectiveness of the material's attenuation properties by providing an air gap in-between the treatment material and the boundary it is attached to... Again, this is largely dependent on the material being used )

And because of the density and mass - or more accurately, the lack thereof - your current use of 2" "acoustic" tiles placed behind the monitors, (or anywhere in the room for that matter) isn't doing anything to help those lo end frequencies. It will help with mids and hi's, and tame some flutter echo and "pinging" in the room, but it's not doing anything for problematic low frequencies.

As Hawk mentioned, the low end on the speakers will emanate in all directions, so... even if the material you are using would be dense enough to be effective, placing the treatment behind the monitors is only one area of many that you need to be concerned with.

I think your best bet would be to measure the room before you look into upgrading your current monitors ( you may find out that your current KRK's will work just fine once they are used in a room that has been acoustically adjusted)... and I certainly wouldn't just start randomly installing various materials to your walls and ceilings ( or your floors) until you get an idea of just what issues you are treating for.

I don't think you'd be doing anything wrong by installing some corner bass traps, I think most experts (of which I am most definitely NOT) would tell you that you'll likely end up having to treat your corners anyway, but beyond that, I wouldn't just start throwing up 1" or 2" Auralex / Sonex tiles "randomly"... I think you need to figure out what your problems are before you start adding treatment to the room.

Brien ( @Brien Holcombe ) is our resident bad-ass when it comes to acoustics. Perhaps he can chime in here with further info regarding port-filling and speaker placement, along with perusing the thread and making sure that I haven't given you inaccurate info ...

You've mentioned your room dimensions being 11 x 15 ft x 9ft... I'm pretty sure that Brien will probably also want details of the shape of the room, dimensions of certain walls... and probably also an idea of the materials that the room is made of ( plaster, wood, drywall, windows, doors, drop ceiling, wood floors, carpet, etc). Pictures and drawings showing the room's layout can also be very helpful.

FWIW

-donny

Sean G Sun, 09/13/2015 - 08:22

DonnyThompson, post: 432382, member: 46114 wrote: Brien ( [[url=http://[/URL]="http://recording.or…"]@Brien Holcombe[/]="http://recording.or…"]@Brien Holcombe[/] ) is our resident bad-ass when it comes to acoustics. Perhaps he can chime in here with further info regarding port-filling and speaker placement, along with perusing the thread and making sure that I haven't given you inaccurate info ...

You've mentioned your room dimensions being 11 x 15 ft x 9ft... I'm pretty sure that Brien will probably also want details of the shape of the room, dimensions of certain walls... and probably also an idea of the materials that the room is made of ( plaster, wood, drywall, windows, doors, drop ceiling, wood floors, carpet, etc). Pictures and drawings showing the room's layout can also be very helpful.

Thanks Donny, all sound info there to take into account.

DonnyThompson, post: 432382, member: 46114 wrote: I think your best bet would be to measure the room before you look into upgrading your current monitors ( you may find out that your current KRK's will work just fine once they are used in a room that has been acoustically adjusted)... and I certainly wouldn't just start randomly installing various materials to your walls and ceilings ( or your floors) until you get an idea of just what issues you are treating for.

Thats also worth considering, no good throwing money into new monitors until I look at how to improve the room treatment with regards to doing it right.:D

OBrien Sun, 09/13/2015 - 11:40

b) Does it effect the driver response by restricting the air pressure / flow thereby limiting the driver travel or slew the response?

Back in the day we heard that sticking a potato into the tailpipe of a car would create a buildup and shoot the potato out. Sometimes it changed the flow and the vehicle would sputter for a while and then die.

Come to find out, it was just a bad idea and caused an other wise well tuned system to behave poorly or cause damage or both.

So would I do it? The potato...hell yes! The bass port...no way.

Sean G Sun, 09/13/2015 - 17:50

DonnyThompson, post: 432382, member: 46114 wrote: Brien ( [[url=http://[/URL]="http://recording.or…"]@Brien Holcombe[/]="http://recording.or…"]@Brien Holcombe[/] ) is our resident bad-ass when it comes to acoustics. Perhaps he can chime in here with further info regarding port-filling and speaker placement, along with perusing the thread and making sure that I haven't given you inaccurate info ...

You've mentioned your room dimensions being 11 x 15 ft x 9ft... I'm pretty sure that Brien will probably also want details of the shape of the room, dimensions of certain walls... and probably also an idea of the materials that the room is made of ( plaster, wood, drywall, windows, doors, drop ceiling, wood floors, carpet, etc). Pictures and drawings showing the room's layout can also be very helpful.

Brien, I may ask you for some expert advice regarding room treatment in this thread shortly if you don't mind.
I shall endeavour to draw up a room diagram as suggested by Donny with dimentions and construction materials of the room and if its OK I'll rack your brain on which way would be the best way to improve the room in regards to treatment with thought going into the rooms use (ratio @ mixing 60 % to live tracking 40%).
I'm sure that different specific treatments may be required for each scenario in regards to room use, while I'm trying to kill two birds with one stone due to space limitations, I'm sure this may be a determining factor in what would be the best way to make / improve the room for a dual purpose use over my current set-up, which is pretty basic and coupled with the limited knowledge on the subject I have gained before starting this thread..
Your advice as recommended by Donny would be wise before I even consider spending a cent on acoustic treatments, let alone consider upgrading my current monitors, if this is required at all.
Many thanks to everyone who has shared their knowledge & thoughts up to now.

OBrien Sun, 09/13/2015 - 18:05

Sure...you can start with this here link. http://recording.org/threads/newbie-control-room-acoustic-treatment-help.55413/
Some knucklehead called "Space" gives a great introductory on basic mix positions. Its good stuff and can be trusted, no testing involved since that has already been handeled by the Masters we follow.

Also, go to http://www.bobgolds.com/Mode/RoomModes.htm and plug in your room measurements. With a 1,400 cubic foot room like yours, you still have low frequency issues but they start to become not as bad as a typical 9X11X8 bedroom. So bass trapping is still needed at least in front of the mix.

The Bonello curve on your existing space is nice and smooth...that is considered a good thang :)

Oh, and get Sketchup... http://www.sketchup.com/

Sean G Tue, 09/22/2015 - 03:12

Ok, so Iv'e stumbled my way through Sketchup, and in no means being an architect, :p I have come up with a very rudimentary room sketch.
The room I am looking to move my set-up into is a secondary room at the back of the house, a lot quieter and away from the current location near the front of the house & major thoroughfare / entry.
It is a little smaller than the current set-up, so its more closer to the typical 9x11x8, it is actually 12x8.5x8.

Unfortunately, what I trade off in size I gain in the room being in a quieter location in the house, plus it adjoins a large rumpus room approx 3 times this size in length which is ideal for tracking in.(And also closer to my pianos...bonus)

Please...hold your laughter :LOL:until you see my sketch...lol:ROFLMAO: (I apologise to those in advance who have more experience with this program)

The room is constructed of plasterboard (drywall) single skin on an oregon frame (was lined in the 60's by my father) with no insulation.
The ceiling is also plasterboard with crown moulding cornice. There is a solid timber door at one of the shorter 8'5" ends, the opposite shorter 8'5" end has a double sash style window with a softwood (meranti?) type frame with single pane glass, with heavy fabric vertical blinds from one corner of the wall. The flooring is a pine timber floor with hard wearing/high traffic short pile carpet with a rubber underlay.

My plan is to have my desk /pc / monitors centred along one of the larger 12' walls. The desk measures 6'3" long.

The room is located in a back corner of the house situated approx 24' from the neighbours house. Although it is closer than I would like, the neighbour has just built a double brick house on the block, lives alone (has resided there all her life, so we get along) and is the head of music at the local secondary school, so doesn't mind at all if she hears a little noise. The main living area of the adjoining house is situated at the front of that house so not too close to where I'm located on my block.

I have put my room dimensions into -

Brien Holcombe, post: 432398, member: 48996 wrote: http://www.bobgolds.com/Mode/RoomModes.htm

as suggested by you Brien and have come up with the following Bonello curve for the 12x8.5x8 (see below)

How does this result look??? Good /Bad /Ugly???

Any suggestions as to which way I should go in regards to room treatment?:confused:

Thanks to all in advance for any suggestions put forward.

- Sean.

Attached files

Brother Junk Mon, 08/15/2016 - 12:08

Blocking the bass port will absolutely change the response. I've built and measured so many driver cabinets it makes me dizzy to think about it.

Long story short, drivers are built to work optimally in certain cabinets. The specs of the driver's suspension will dictate how it responds in a particular cabinet. Or what type of cabinet it will work in at all. You have to assume that the mfr knows what they are doing. That's why I often just build it myself lol.

While it will change the fr, who is to say it is for the worse or better unless you have an RTA to get flat and then tune by ear? I read through most of these posts...do none of you have an RTA to measure your rooms? Or some measurement device? Bc almost no room will be flat.

There is an inherent danger in blocking the port. It's one of those things that probably wouldn't happen, but it is theoretically possible. A bass driver's cooling often depends on cone movement. As the cone moves, it wisks air across the voice coil/s. Remember the driver's suspension and box size are correlated. If you block the port, you will likely restrict cone movement, but you are still pumping the same amount of wattage (heat in this case) to the voice coil. So you can cook the voice coil. If you drive your monitors hard, and block the port (which in turn restricts cone movement) for long periods, in theory it's possible. I've only done it once, and it was under extreme circumstances...and not with studio monitors, with a 15" in an 8 ft^3 box tuned to 20 hz...a different world, but do with the info what you like.

Personally, I would try a-periodic membrane before fully blocking the port. And have a way to measure. I use True RTA if I can't get a hold of a Termpro or something. It works well. I forget what mic but it's a behringer condenser and True RTA has the correction files for it.

I am in no way affiliated with True RTA, I'm just telling you what I use.

bouldersound Mon, 08/15/2016 - 12:50

Welcome to the forums. You know this thread is almost a year old, right? And, no, I don't use a simple RTA because they are time blind. I use transfer function software which is capable of, to some degree, unraveling speaker response from room response, something an RTA can't do. RTAs are great for pinpointing feedback frequencies on stage monitors but they suck for room measurement.

Brother Junk Tue, 08/16/2016 - 06:47

Sean G, post: 440545, member: 49362 wrote: What a croc of BS...time travel in theory is possible too...but guess what?...it aint going to happen.

I didn't expect something like this to happen this soon on this site.

Your English, grammar, manners, and logic, all need work. You just stated that it's possible, but also BS (?) You are also saying that time travel and blowing a driver with heat are equally possible. And I'm the "b.s." guy here? But let's start with this...

Sean G, post: 432364, member: 49362 wrote: I would like some advice from members on the topic of blocking the bass ports on nearfield speakers.

Oh, I'm sorry Sean G, here I was thinking I was a member. And one with a fair bit of driver/cabinet experience that could actually answer your question. I was simply doing what you asked in your first sentence. But hey, your a mod...

I thought I explained it pretty well. The driver has a magnet, sitting inside that magnet is a (usually copper) voice coil, that is essentially wound copper thread. Imagine a toilet paper core that you wrapped fine copper thread around. The copper is then glued. The amp sends electricity to that coil, and that makes it move because it's surrounded by a very strong magnetic field. That electricity then becomes heat. At some point, you will reach critical temperature, and the copper either roasts, breaks, or what is often the case, the glue gets fried, releasing all the copper winding, so it will no longer ride freely in the magnet channel. This is why drivers/speakers etc say they can handle 100w rms etc. That's the amount of heat that driver can displace or deal with. That is physics my friend. Sometimes the havoc of the copper unravelling is enough to make the driver stick, sometimes the glue, now a melted mess, once cooled, glues the driver in place.

If the driver doesn't make sound anymore AND

You can move the cone in it's regular motion, and no scratching sound, the coil overheated and cooked or broke. Either way, electricity will no longer pass through it.
You can move the cone but it makes a scratching sound, the voice coil unraveled. That scratching is the sound of the copper rubbing inside the channel.
You can't move the cone at all, the glue melted, and has now glued the driver in place

Let me ask you Sean G, how do you think drivers blow? Does the speaker fairy come down and take it to speaker heaven? 9/10 times it's heat (the other 1 time is usually pushing the cone beyond mechanical limits)(no speaker fairy).

Now, I know your a mod, and I know I would like to continue to come and learn from this site (e.g. not be banned). So I'm only going to intimate stupidity/arrogance. Turnabout is fair-play.

How do we deal with anything that gets too hot? We cool it. With air, water, whatever. Or in the case of these newer "mega-drivers", we add more voice coils/copper, which allows the driver to absorb more heat before failure. This is how many drivers these days accomplish 1000w rms. And most of them also rely on air movement from the cone. The cone is moving anyway, just design the driver so that the movement will also help cool the coil. It works well.

Maybe I need to be hyperbolic. Take your driver, put it face up, and put something heavy on the cone (don't worry about the cone, the driver will be dead in a few minutes anyway) so that the driver cannot move. Now, you are only sending heat to the coil, and the driver cannot cool it at all. A driver that can take say, 100 w rms, feed it 100w rms now, and it will fail in very short order, because the cone is not moving.

Blocking the bass port is nowhere near as drastic. But depending on the driver, it can, and WILL, restrict cone movement, which is real life version of the hyperbole above.

I am the one who said it's unlikely, but possible. You then jump in and say, it's possible, but B.S.? I can't help but wonder if you are piggy-backing for points, or because you think you can push around the new guy. I am new to this forum, and in comparison to yourself, probably newer to this field (production etc) But I've been buying, building, designing drivers and cabinets for 25 years. Even got my share of accolades along the way. If you want to compare posts and info in this thread...I gotta say, yours sounds like the B.s. one. I was just telling people what was theoretically possible because of the design drivers use. Forgive me for not wanting someone to blow their monitors over something silly. I wasn't rude, I was downright pleasant. Is this a place to share facts and experience? Or a place where the older members @#%$ on the perceived newer people?

Sean, if you want to call it B.S. bring some new facts to light, or disprove the ones I brought up. I don't think you have the knowledge to do either based on your initial question. So, I will leave it here if you can. Also, time travel is possible. W/out getting into the cosmological physics of how it exists in space, here on earth we are also time traveling, it's just our perceived "forward." (y)

bouldersound, post: 440544, member: 38959 wrote: Welcome to the forums. You know this thread is almost a year old, right? And, no, I don't use a simple RTA because they are time blind. I use transfer function software which is capable of, to some degree, unraveling speaker response from room response, something an RTA can't do. RTAs are great for pinpointing feedback frequencies on stage monitors but they suck for room measurement.

I appreciate the welcome!

I did notice the age of the thread, but I thought it a topic that was very simple to explain. And it didn't really seem to get resolved here. I felt like I could resolve it.

I have other programs for waterfall plots, time decay etc. I want to say S.a.a.r.t? I haven't used it in a while as it's on a windows machine, and I haven't had reason to use it in a bit. I would respectfully disagree that RTA's suck for room measurement. I think I know what you mean by time blind, but it's an average for the room, and I will have to check this, but the pink noise is a relative constant (to our ears).

But in the way that you mean it, our ears are also time blind no? Our ears don't get to cancel out early/late reflections, it's the average...so how is a measurement that is time blind beneficial? (I'm genuinely asking) But also, we may be talking about entire different spaces. If you have a room with a lot of reflection, I definitely see your point...the RTA is going to be very tricky to sort. I'm a bit OCD when it comes to this, so, I wouldn't ever build a room like that in the first place. A reasonably "dead" room, I've never had a problem using an RTA. That being said, I'm not saying it's the best tool for room measurement, and happily defer to others on whatever that product is.

While I am genuinely interested in what you are saying, perhaps we can talk via PM or whatever. My main point was this; this thread was all about if blocking the bass port will alter the FR. And it appeared that no one had an empirical means of checking that? I'm assuring people it will. For better or worse, it will. But any decent monitor, if the driver is in a ported cabinet, that's likely where the driver will function best.

So the question is, can I take a driver that was intended for a ported enclosure, and block the port to make the monitor function better in the room. If you want to plug the port to see if it helps your room response, more power to you. That's how to truly learn imo. But you need a way to measure it. Or if you can get the t/s parameters of the driver you can input it into some box software and see what will happen. It will tell you the new x-max of the driver etc. If your cone used to travel 12mm total (in your ported box) and in the sealed version it travels 6mm, you have cut your vc cooling in half. Not only that, but your box used to have a "window" (the port breaths to the outside) Now, you have sealed it, so heat builds up easier in the box. The cone doesn't move as much (depending on it's specs) so heat is also building up in the vc. I'm not saying something WILL happen, but if you are going to play like that, I just thought it would be more informative/safer for all, if everyone truly understood what is going on under the hood.

Will it change the FR? Absolutely
Will it change the FR for the better? Only the people in that room could tell you. If it does, it's most likely not a problem w/the cabinet, but a problem with the room/placement/compatibility.
Will it kill my monitors? Unless you are driving them pretty hard for long periods, probably not. But understand, heat is the #1 enemy of a driver. You had a box that breathed before, and now it's closed. So heat from the driver stays inside, if you are active, heat from the amp stays inside. Imagine your car on a hot day with a window wide open, vs. all windows closed. In this analogy, the solar gain is like the heat build up from closing the port. Do what you like, but understand that is what is happening. And all of this is the result of the sealing of the box, and the suspension design of the driver. So, I can't tell you that I plugged my HS8's and they were fine, so you can plug the ports on your JBL's and it will be ok. It's different drivers.

I hope this was at least somewhat educational to someone.

bouldersound Tue, 08/16/2016 - 10:31

No, really, welcome. I'm all for a fact based approach.

Some powered speakers probably do rely on cabinet ventilation for cooling. For a passive speaker running well below it's rated maximum output it's probably inconsequential. I think that may be the basis of the B.S. comment. PA speakers are different from studio monitors because they're big and you have to move them around. You naturally want to get the maximum output for a given size and weight so you assume they'll be run at or near maximum output much of the time. When riding the edge like that one little change, like a blocked port or a HPF set incorrectly can let the smoke out of the voice coils. Studio monitors just aren't run near their limits much so they tend to have capacity to spare.

Yes, SMAART is one, TEF and SIM are two others. I use REW because I'm cheap. RTAs only see amplitude and frequency. Transfer function software adds time to the equation, which allows it to separate source from reflections. Yes, the ear is sort of time blind like an RTA, which is one reason you need a tool that is not time blind. The ear has advantages that a measurement tool does not, paired receptors and comparative processing. That is, we have two ears and binaural perception. So we get arrival times, head shading and pinna effect which our brains process to extract directional cues. We can tell the difference between source and reflection by direction. Transfer function software relies on generating its own signal and detecting the time(s) it takes to reach the mic to distinguish them.

You know, it's not that hard to calculate the right box and port design for a given driver. If that wasn't done or wasn't done correctly by the manufacturer then blocking the port isn't likely to make it more accurate, just different.

And, for your amusement, one of my "learning experiences":

Brother Junk Tue, 08/16/2016 - 11:49

bouldersound, post: 440554, member: 38959 wrote: No, really, welcome. I'm all for a fact based approach.

Really, Thank you.

bouldersound, post: 440554, member: 38959 wrote: Some powered speakers probably do rely on cabinet ventilation for cooling.

If it's mfr'd by anyone with a brain/education in this field, it's definitely factored in. Probably not a problem most of the time, but someone is getting paid to think about it. If you have an amp and a driver in the same enclosure, it has to be thought about. Take a driver that uses a vented pole piece like this. The design incorporates cooling to the coil. What do you suppose happens if you plug that hole? The voice coil will be hotter. On a smaller scale, the same will happen by plugging the port of an enclosure. It's unlikely to be a problem, but, I've killed a driver that way, once.

bouldersound, post: 440554, member: 38959 wrote: Studio monitors just aren't run near their limits much so they tend to have capacity to spare.

I agree, that's why I qualified by saying pumping them for extended periods. I just wanted people to understand what was happening.

bouldersound, post: 440554, member: 38959 wrote: You know, it's not that hard to calculate the right box and port design for a given driver. If that wasn't done or wasn't done correctly by the manufacturer

In a round-a-bout way, that's my point. The driver and the enclosure are a match by design. If something isn't right (assuming quality monitors) it's most likely not the driver enclosure. That doesn't rule out the possibility that it could, potentially, make a beneficial change in a room, but I doubt it.

The potentially serious issue heat wise, is changing the suspension of the driver. Since most drivers these days have a large x-max, they use that movement to their benefit. If you alter the travel significantly, which you "could" by blocking the port, you are pumping the same wattage to a coil, but it's not cooling itself as efficiently.

Lol @ your driver failure. That's a doozie. Appears to be mechanically induced failure, if I'm wrong I'd be curious. I'll see your mechanical failure. This driver was working fine, then all of a sudden a loud snap came out of the port. It was no doubt a mfr failure that just manifested itself later, but it is a funny one. You seldom pull a previously working driver from an enclosure in this condition.

Sean G Tue, 08/16/2016 - 16:13

Brother Junk, post: 440553, member: 49944 wrote: was simply doing what you asked in your first sentence. But hey, your a mod...

Being a mod has nothing to do with my response

Brother Junk, post: 440553, member: 49944 wrote: Your English, grammar, manners, and logic, all need work

My english, grammar, manners and logic are all fine thank you

How do explain unported speakers?...are they just bought to us by your so-called speaker fairy ?...or are they irrelevant as they do not factor into your logic ?

Brother Junk, post: 440553, member: 49944 wrote: I did notice the age of the thread, but I thought it a topic that was very simple to explain. And it didn't really seem to get resolved here

It did get resolved...the ports were not blocked up...you are about 12 months too late to the party

Brother Junk, post: 440553, member: 49944 wrote: I don't think you have the knowledge to do either based on your initial question.

Please, enlighten me, as you seem to be the one who has an answer for everything

OBrien Tue, 08/16/2016 - 17:56

Mans got chops...good luck Junk...it is difficult to walk in here and address things without validation...especially when you kinda attack a resident. You will get better and they will respect your education in this area....or you will show your google experience and vanish.

Choice is yours...be strong...and be right.

Brother Junk Wed, 08/17/2016 - 07:20

Brien Holcombe, post: 440569, member: 48996 wrote: Mans got chops...good luck Junk...it is difficult to walk in here and address things without validation...especially when you kinda attack a resident. You will get better and they will respect your education in this area....or you will show your google experience and vanish.

Choice is yours...be strong...and be right.

Brien,

First off, I appreciate the support. There are a lot of "sub-fields" to this career in which, I'm am 100% confident, if I were enter into a "knowledge duel" with Sean G, he would kick my arse from wall to the other. You would be scraping me off the ceiling (metaphorically speaking).

But, this isn't one of them. And from what I can see, the knowledge gap here is so wide, Sean G seems to have fallen in. I have challenged him to either disprove what I've said, or bring new facts to light. He hasn't done either one. (Nor can he, what I'm telling you is how it works).

However, ime, in situations like this, what usually happens is the attacker eventually concedes, or recognizes I'm not talking out of my butt and we become friends. That's how it happens almost every time. The last person I got in a tangle with (different subject altogether), I talk to frequently now...he even mailed me a gift! Sometimes it just takes a bit for a place to get used to your style. So, I look forward to getting this over with and learning from Sean in the ways his knowledge is superior to mine. Which as I said, I'm sure, there are many. It's just not this one.

Sean G, post: 440560, member: 49362 wrote: My english, grammar, manners and logic are all fine thank you

That's what most board bullies say. Read your response to my, informative, and happy post. Then you came along and said everything was B.S. and implied everything I stated was as plausible as time travel. I can take a punch, but remember...turnabout.

Sean G, post: 440560, member: 49362 wrote: It did get resolved...the ports were not blocked up...you are about 12 months too late to the party

I see. So I missed a post (still missing it, but that might be me) that detailed what happens when you block the port. What is your problem?

Sean G, post: 440560, member: 49362 wrote: Please, enlighten me, as you seem to be the one who has an answer for everything

Certainly not everything. But I have an answer for this thread and the couple other things you have entered into it. That is all I have addressed. Again, what is your problem?

Sean G, post: 440560, member: 49362 wrote: How do explain unported speakers?...are they just bought to us by your so-called speaker fairy ?...or are they irrelevant as they do not factor into your logic ?

I really do mean it when I say I look forward to putting this behind us and learning. But for now...

I have mentioned, several times now, the suspension of the driver, is correlated to the box design. A driver in a sealed cabinet, (unless YOU built it lol) was meant to be there. The suspension is designed to work in that environment, a weak vacuum of sorts. The box will compliment the mechanical limits of the sub. So, the driver is traveling along it's safe limits, cooling the coil as it moves. I'm not even sure of what you are getting at with this question, but if you mean that heat will build up in the box, I've stated several times, the problem with blocking the port is excess heat build up in the coil because you have restricted cone movement. The fact that the heat now has nowhere to go was just a side point. Perhaps it was a mistake adding that. It's true, but I seem to have confused you further.

Look at it this way...

The reverse of your initial question would be a driver that is in a sealed box, and we decide to port it. But instead of heat being an issue (the box will be cooler actually) now we run into an issue called unloading, which will especially affect a "sealed" spec driver. Any frequencies played a few hz below the port tune, the driver's suspension will often bottom out and cause a structural (mechanical) failure. This is most likely what happened in the pic above mine (not unloading per se, but exceeding the mechanical limits) I can't see the coil to be conclusive, but that type of damage is usually what you see when a driver has handled the heat, but we exceeded the mechanical limitations. It bottoms out, or pushes out too far and the coil structure gets hung up on something thus breaking the cone And in the real world, this would kill a driver much more often than your initial question (sealing a ported cabinet).

Now a driver in a ported cabinet, the suspension was designed to be in a ported box. IF you seal that box, because of the way a ported spec driver works, you are most likely restricting cone movement. You are putting the driver in, for lack of a better term, a loose vacuum, or a box so small, it will suffocate the driver. When a driver is working correctly, the more power you push to the coil, the more cone travel there is, which = cooling. It is balanced.

If you restrict cone movement, you restrict cooling. Every stroke that cone makes, brings a wave of air across the coils, constantly cooling them. It acts like a fan blowing across the coils at all times. If you make changes to the box design that effectively pump the same heat to the coil, but reduce cone stroke, you are cooling the coil that much less. You are dialing down that "fan" action. Try it yourself, stop a cone from moving at all, and bump the drivers for a bit. It will fail in very short order. Because that cone travel/cooling, is part of the design. It's really not that hard to understand. And if you plug the port, and I'm giving a very loose "average" here based on recollection of drivers I've experimented with (every driver is different) you could reduce cone travel 20-70%. That's 20-70% less cooling. Get it? So now, the same driver, same wattage, is MUCH more likely to fail or shorten the life span.

I just thought people should know that before sealing their boxes.

Apparently you don't believe me, or you don't like that I mentioned it. Either way, you're drowning in the shallow end of the knowledge pool in this topic so just let it go. I didn't come here to cause problems. Especially not with a mod. I came here to learn, and where I can, teach. And I seldom step out of my box when it comes to the latter.

How bout some speaker porn Seas Excel Lotus 6.5"s They are a royal pita to work with, but I've yet to hear better midrange when they are done right.

Sean G Wed, 08/17/2016 - 21:05

Seriously...I have come across some downright idiots in my time, but you take the cake.

Firstly, I did not attack you or bully you...my one line post (as the OP of the thread mind you) was the following -

Sean G, post: 440545, member: 49362 wrote: What a croc of BS...time travel in theory is possible too...but guess what?...it aint going to happen.

Where is the attack in that?...If you cannot handle someone who doesn't take everything you state as gospel or agree with you, taking it on board as some sort of personal attack, then you don't belong on forums of any kind.

Brother Junk, post: 440553, member: 49944 wrote: I didn't expect something like this to happen this soon on this site.

Your English, grammar, manners, and logic, all need work. You just stated that it's possible, but also BS (?) You are also saying that time travel and blowing a driver with heat are equally possible. And I'm the "b.s." guy here? But let's start with this...

Oh, I'm sorry Sean G, here I was thinking I was a member. And one with a fair bit of driver/cabinet experience that could actually answer your question. I was simply doing what you asked in your first sentence. But hey, your a mod...

I thought I explained it pretty well. The driver has a magnet, sitting inside that magnet is a (usually copper) voice coil, that is essentially wound copper thread. Imagine a toilet paper core that you wrapped fine copper thread around. The copper is then glued. The amp sends electricity to that coil, and that makes it move because it's surrounded by a very strong magnetic field. That electricity then becomes heat. At some point, you will reach critical temperature, and the copper either roasts, breaks, or what is often the case, the glue gets fried, releasing all the copper winding, so it will no longer ride freely in the magnet channel. This is why drivers/speakers etc say they can handle 100w rms etc. That's the amount of heat that driver can displace or deal with. That is physics my friend. Sometimes the havoc of the copper unravelling is enough to make the driver stick, sometimes the glue, now a melted mess, once cooled, glues the driver in place.

If the driver doesn't make sound anymore AND

You can move the cone in it's regular motion, and no scratching sound, the coil overheated and cooked or broke. Either way, electricity will no longer pass through it.
You can move the cone but it makes a scratching sound, the voice coil unraveled. That scratching is the sound of the copper rubbing inside the channel.
You can't move the cone at all, the glue melted, and has now glued the driver in place

Let me ask you Sean G, how do you think drivers blow? Does the speaker fairy come down and take it to speaker heaven? 9/10 times it's heat (the other 1 time is usually pushing the cone beyond mechanical limits)(no speaker fairy).

Now, I know your a mod, and I know I would like to continue to come and learn from this site (e.g. not be banned). So I'm only going to intimate stupidity/arrogance. Turnabout is fair-play.

How do we deal with anything that gets too hot? We cool it. With air, water, whatever. Or in the case of these newer "mega-drivers", we add more voice coils/copper, which allows the driver to absorb more heat before failure. This is how many drivers these days accomplish 1000w rms. And most of them also rely on air movement from the cone. The cone is moving anyway, just design the driver so that the movement will also help cool the coil. It works well.

Maybe I need to be hyperbolic. Take your driver, put it face up, and put something heavy on the cone (don't worry about the cone, the driver will be dead in a few minutes anyway) so that the driver cannot move. Now, you are only sending heat to the coil, and the driver cannot cool it at all. A driver that can take say, 100 w rms, feed it 100w rms now, and it will fail in very short order, because the cone is not moving.

Blocking the bass port is nowhere near as drastic. But depending on the driver, it can, and WILL, restrict cone movement, which is real life version of the hyperbole above.

I am the one who said it's unlikely, but possible. You then jump in and say, it's possible, but B.S.? I can't help but wonder if you are piggy-backing for points, or because you think you can push around the new guy. I am new to this forum, and in comparison to yourself, probably newer to this field (production etc) But I've been buying, building, designing drivers and cabinets for 25 years. Even got my share of accolades along the way. If you want to compare posts and info in this thread...I gotta say, yours sounds like the B.s. one. I was just telling people what was theoretically possible because of the design drivers use. Forgive me for not wanting someone to blow their monitors over something silly. I wasn't rude, I was downright pleasant. Is this a place to share facts and experience? Or a place where the older members @#%$ on the perceived newer people?

Sean, if you want to call it B.S. bring some new facts to light, or disprove the ones I brought up. I don't think you have the knowledge to do either based on your initial question. So, I will leave it here if you can. Also, time travel is possible. W/out getting into the cosmological physics of how it exists in space, here on earth we are also time traveling, it's just our perceived "forward." (y)

I appreciate the welcome!

I did notice the age of the thread, but I thought it a topic that was very simple to explain. And it didn't really seem to get resolved here. I felt like I could resolve it.

I have other programs for waterfall plots, time decay etc. I want to say S.a.a.r.t? I haven't used it in a while as it's on a windows machine, and I haven't had reason to use it in a bit. I would respectfully disagree that RTA's suck for room measurement. I think I know what you mean by time blind, but it's an average for the room, and I will have to check this, but the pink noise is a relative constant (to our ears).

But in the way that you mean it, our ears are also time blind no? Our ears don't get to cancel out early/late reflections, it's the average...so how is a measurement that is time blind beneficial? (I'm genuinely asking) But also, we may be talking about entire different spaces. If you have a room with a lot of reflection, I definitely see your point...the RTA is going to be very tricky to sort. I'm a bit OCD when it comes to this, so, I wouldn't ever build a room like that in the first place. A reasonably "dead" room, I've never had a problem using an RTA. That being said, I'm not saying it's the best tool for room measurement, and happily defer to others on whatever that product is.

While I am genuinely interested in what you are saying, perhaps we can talk via PM or whatever. My main point was this; this thread was all about if blocking the bass port will alter the FR. And it appeared that no one had an empirical means of checking that? I'm assuring people it will. For better or worse, it will. But any decent monitor, if the driver is in a ported cabinet, that's likely where the driver will function best.

So the question is, can I take a driver that was intended for a ported enclosure, and block the port to make the monitor function better in the room. If you want to plug the port to see if it helps your room response, more power to you. That's how to truly learn imo. But you need a way to measure it. Or if you can get the t/s parameters of the driver you can input it into some box software and see what will happen. It will tell you the new x-max of the driver etc. If your cone used to travel 12mm total (in your ported box) and in the sealed version it travels 6mm, you have cut your vc cooling in half. Not only that, but your box used to have a "window" (the port breaths to the outside) Now, you have sealed it, so heat builds up easier in the box. The cone doesn't move as much (depending on it's specs) so heat is also building up in the vc. I'm not saying something WILL happen, but if you are going to play like that, I just thought it would be more informative/safer for all, if everyone truly understood what is going on under the hood.

Will it change the FR? Absolutely
Will it change the FR for the better? Only the people in that room could tell you. If it does, it's most likely not a problem w/the cabinet, but a problem with the room/placement/compatibility.
Will it kill my monitors? Unless you are driving them pretty hard for long periods, probably not. But understand, heat is the #1 enemy of a driver. You had a box that breathed before, and now it's closed. So heat from the driver stays inside, if you are active, heat from the amp stays inside. Imagine your car on a hot day with a window wide open, vs. all windows closed. In this analogy, the solar gain is like the heat build up from closing the port. Do what you like, but understand that is what is happening. And all of this is the result of the sealing of the box, and the suspension design of the driver. So, I can't tell you that I plugged my HS8's and they were fine, so you can plug the ports on your JBL's and it will be ok. It's different drivers.

I hope this was at least somewhat educational to someone.

Then you go on with this half page rant where you actually attack me, where you make claims that I attacked you and bullied you, which in fact is the opposite of what actually happened, contrary of what you think happened in that head of yours.

Brother Junk, post: 440553, member: 49944 wrote: Turnabout is fair-play.

Oh yeah, I get that, considering you managed to turn it all around and make out it was me having a go at you personally...when in fact you got in with the personal attack towards me quoting the following -

Brother Junk, post: 440553, member: 49944 wrote: Your English, grammar, manners, and logic, all need work.

Then you follow it up with this classic

Brother Junk, post: 440553, member: 49944 wrote: I can't help but wonder if you are piggy-backing for points, or because you think you can push around the new guy.

I got some news for you sunshine...this has nothing to do with you being the new guy whatsoever, or about point scoring. There are plenty of posts here on RO if you had even bothered to look prior to working those little fingers overtime on the keyboard, or bother to look now, where new members have come onto the forum that I have welcomed and helped. In many cases, if you again had bothered or bother to look now, you will see on many occassions I am usually the first to welcome and help them. So get your facts straight before you go posting claims about others you do not either know or know anything about. Rookie error #1

Brother Junk, post: 440553, member: 49944 wrote: Now, I know your a mod

Being a mod does not mean I give up my right to have an opinion. Like I stated above, if you cannot handle the opinion of others who do not hold the same view as you on forums, them maybe you are too thin-skinned to participate, going by the way you go off half-cocked accusing others of attacking and bullying you who disagree with you. Rookie error #2.

I resent the statement you imply that I bully others on forums, let alone this one. I was asked by the administrator of this forum to be a mod because of my participation on this forum and because of my character, two things you know absolutely nothing about. You have been here 5 minutes, you accuse me of bullying you, then you start throwing mud.
So before you come onto a public forum and think you can start throwing accusations around about members that are unfounded, moderators or not, think again. Rookie error #3.

One thing that really annoys me, is when new members come onto a forum, without any form of introduction of who they are or what they do (yes, if you had done your research here before blowing off at the mouth you may have found that thread instead of searching for the first and only thing you probably know about), then they inject themselves into the conversation by sharing their "expertise" on subject matters to try to impress other members...trying to throw their "intellectual weight" around, so to speak. This is not a pissing contest, contrary to what you believe.
When these people are called out for what they usually are, which in 99% of the cases are no more than google researchers, they drop off never to be seen again. Most of these types garner their so-called "expertise" from google them parlay it parrot fashion to try become part of the conversation.

Now, I'm not accusing you of this, heaven forbid after the way you carried on after my initial one-liner, but, I must say you are starting to resemble it...I've seen it before and not just here on RO. The internet has florished a whole new breed of those who are the types who stand around in the dark corners at social gatherings not saying a world for fear of being corrected, but try to lead and direct conversation when veiled by the annonimity of a keyboard and a chat forum. When anyone questions their logic, or dare I say disagree with their statements, they take it as a personal attack on themselves then defend themselves the only way they know how...by accusing others of attacking them and throwing mud to deflect the fact that what they state or proclaim or who they are may have been called into question.
But these types soon get found out and called out for what they are....mere charlatans.

RO is a problem based learning forum, new members are welcome any time, in my time here as a member then as a moderator I have always welcomed and helped new members.
Sure, there is debate, thats how we learn. Sure there is disagreement on a range of topics, and hardy, at times robust debate at that. But if you cannot handle someone who does not agree with you, then maybe it is not for you. And don't come into this forum throwing mud. We don't need people like that in our house. If you cannot handle people who do not agree with you or your opinion, then maybe you should join the other cork-sniffers at Speakerafficionardo.com

In summing up...

Brother Junk, post: 440580, member: 49944 wrote: However, ime, in situations like this, what usually happens is the attacker eventually concedes, or recognizes I'm not talking out of my butt and we become friends. That's how it happens almost every time.

That's how it happens almost every time,eh?...do you go onto forums and make a habit of this, do you?...sounds like you have form in this area going by that statement of your first-hand experience at situations like this.

You think you can personally attack me on a public forum, and I'll have anything to do with you in the future?...and I thought from your earlier posts you were seriously deluded...

You have done your dash with me...and I wouldn't have anything to do with you if we were the last two people left on RO.

- Sean.

EDIT :- How's the english and the grammar ?.....good enough and clear enough for you ?

Brother Junk Thu, 08/18/2016 - 07:36

Wow, I really hurt your feelings lol. (and I didn't even read most of your post :)

I'm bored with this, let's just put it to bed.

Tweeter's aside, most drivers are "air cooled."

If you seal a ported box, the likely outcome is to restrict cone movement. Not every driver, but most, that would be the result. That inhibits the built in air cooling. A driver that used to be able to handle a genuine 100w rms, now, will not. So you sealed off the port noise that was causing you problems or whatever it was doing, but now, you should be aware, that your driver is most likely running hotter. Run 'em that way if you want. The best way to learn is to botch something up. But some people would rather have it explained to them ahead of time.

I thought it would be good for people to know. As I said, I've done it, once. And the reason for the failure was confirmed by the speaker designer at Kove Audio (no longer in biz) who is a friend of mine.

I played too much with box specs, and markedly reduced power handling...by blocking the port. I reduced power handling because I reduced the cone stroke to wattage ratio. It's not hard to understand.

It's an unlikely outcome to blow your monitors up, but repeating myself, it depends on how hard and long you bump them. But it is possible. You should at least know, your drivers will be running hotter. And I can't tell you how much hotter, because every driver is different.

Sean G, post: 440590, member: 49362 wrote: EDIT :- How's the english and the grammar ?.....good enough and clear enough for you ?

Still pretty bad buddy. Here is the correction, since you asked.

How is the English and grammar? Is it good enough for you? Is it clear enough for you? (not how I would choose to write it, but I'm trying to use your words)

DonnyThompson Fri, 08/19/2016 - 02:26

Brien Holcombe, post: 440603, member: 48996 wrote: Frankly I thought my potatoe in the tailpipe was sufficient enough

See, that's where I went wrong. Instead of plugging the ports on a pair of Event passives with Roxul, I shoulda used a potato instead... more to the point, not a Redskin, but a Russet.

Sigh.... Live and learn.

;)

Brother Junk Fri, 08/19/2016 - 07:57

DonnyThompson, post: 440610, member: 46114 wrote: See, that's where I went wrong. Instead of plugging the ports on a pair of Event passives with Roxul, I shoulda used a potato instead... more to the point, not a Redskin, but a Russet.

Sigh.... Live and learn.

;)

If you would have simply asked about putting potatoes in ports I could have given you data sheets to show the differences. Potato plugged vs non potato plugged. Redskin vs Regular etc.

Beets are the better option. Not because of performance, but because of the pun. The beats aren't right w/o the beets.

Do not cook your beet plugs though. And organic beets will sound more natural, less phase-y.

For real though, I'm sorry for letting myself turn into an arse over this thread. Everything I said is the absolute truth, but I shouldn't have let myself get irritated over it.

And I sincerely apologize to Sean G. Whether he has me on ignore by now or not, I truly am sorry. There are about 4 things in this world I know a lot about. Decades of experience "in the trenches" (going on 3 for some) Dogs, Horses, Drivers/designs/crossovers, and building race cars/racing. Most other subjects, I'm fine with being told (essentially) that I don't know what I'm talking about. I can be very humble. I can also be prideful. And I was prideful.

I should have handled it a different way, so, apologies to all.

P.s. DonnyThompson

Congrats on breaking the, what was it, 58 year curse? Maybe you don't care about sports, I don't know. But I'm happy for all the people in Believeland.

DonnyThompson Fri, 08/19/2016 - 13:02

Brother Junk, post: 440614, member: 49944 wrote: congrats on breaking the, what was it, 58 year curse? Maybe you don't care about sports, I don't know. But I'm happy for all the people in Believeland.

I appreciate that... it was a nice diversion for us, especially since the RNC rolled into town two weeks later, LOL. Then again, the Browns lost to the Falcons last night, so I can already here people saying "well, guess we'll get 'em next year..."

;)