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Proper use of the preamps

My converter and i/o is the Mbox Pro (3rd generation in case it matters)

It uses the preamp if it's switched to Mic. It does not apply the preamp section with line inputs.

I have a set of Roland TD-11's that have a line out, L/R. When I first set them up I got almost no volume at all. With everything cranked, it was barely even audible. The kind people here helped me figure out that it was the fact that I was using stereo cables instead of mono. I didn't know it mattered going from S > M, but I switched out the cables for mono, and the volume problem was gone.

So, it's mostly gone. If I plug the drums in the rear (this post is just full of double entendres) it's line level, no preamp. There is a sensitivity switch in the back of -10db or +4db (iirc) which is set to +4 and the drums are fairly quiet. With the brain showing 5 bars of output (clipping) PT maxes out at 3 bars. I have to crank the track the whole way to get the right volume. So one question I have is, if I turn down the volume from the brain so it's not sending clipped signal (the brain of the TD-11 has a volume knob that controls headphone out and line out) but kept the PT track at +12db, is there anything inherently wrong with that?

My second question is about the mic section. If I move the drums to the front side of the Mbox, it's mic level (is there a better term for that?) input so it runs through the preamp section of the Mbox. When I connect them this way, I can turn the volume up, and THEN, I don't have to crank the PT track.

Is there anything "wrong" with doing it that way?

This is what I would think is ideal; turn the volume on the drums down so it's nowhere near clipping. Run them through the preamp section and amplify the signal from the Mbox, bc it's probably the best piece of equipment I have. But I'm not sure if there is something I'm not thinking about/aware of, e.g. am I going to cause a failure by running the drums through the preamp section. I would think it doesn't matter so long as the signal isn't too hot, which it obviously isn't.

Comments

Kurt Foster Mon, 10/31/2016 - 11:52
use the -20 setting on the line inputs. most keyboards / drum machines and other line level devices run at -20 or -10. it's rare you will find a line level device that runs at +4 unless it's a piece of pro gear like an LA2a limiter.
btw, i'm pretty sure the line level ins on the MBox still go through the mic pres. they are just padded down. it's not a true preamp bypass. (just for future reference)

Brother Junk Tue, 11/01/2016 - 09:34
Kurt Foster, post: 442815, member: 7836 wrote: use the -20 setting on the line inputs. most keyboards / drum machines and other line level devices run at -20 or -10. it's rare you will find a line level device that runs at +4 unless it's a piece of pro gear like an LA2a limiter.

Thanks, in the back there is only -10/+4. They are both way too quiet.

The -20db is only on the front inputs, if you pull the knob out.

But I think they just need to go in the front inputs. Plugging it into line level is just way too quiet. And I think this is why, (from the manual)

"DI Input (Front Panel) Instruments such as elec- tric guitar or electric bass that usually have a lower level of output than line level instruments use the front panel DI (“Direct Inject”) input. " So the Rolands must just fall in that category.

Kurt Foster, post: 442815, member: 7836 wrote: btw, i'm pretty sure the line level ins on the MBox still go through the mic pres. they are just padded down. it's not a true preamp bypass. (just for future reference)
I looked everywhere for where I found that and I can't find it. I believe you are correct...it didn't make sense to me either, but I'm positive I didn't pull it from thin air. I would think that it must run through the preamp stage. But that's what I read....it's gonna bug me till I find it.

The front inputs, at 11 o'clock, with the soft limiter on, and with the brain set to about 75% output and it sounds good.

I was just worried that I might damage something, but apparently those two front inputs are fine for any level input.

Boswell Tue, 11/01/2016 - 09:46
From the SOS review of the MBox 3rd generation:
Also worth noting is that, as on previous Mboxes, the line inputs also pass through the preamps. This is great if you have old analogue synths that put out weird and unpredictable levels, less good if you want to accurately transfer a stereo signal from another source.

Brother Junk Tue, 11/01/2016 - 11:39
pcrecord, post: 442882, member: 46460 wrote: I have a TD-9 and always used it with a DirectBox. Lately I also used the instrument input on my ISA preamps.
A DI might be something to try (if you have one)
If you mean direct inject, that's what the two fronts are apparently. To be humbly honest, I've never heard that term. Alas the front of the Mbox is labeled "Mic/DI"
So, I guess the fronts are a free for all. It's got the -20db attenuation, so a very hot LI, a normal LI, instrument, mic, whatever.

My question was based on the premise that the LI's don't use a preamp path. And also that the TD-11's are line level out. Neither of those is correct. So I needn't worry about damaging anything.

TY

pcrecord Tue, 11/01/2016 - 12:48
Brother Junk, post: 442885, member: 49944 wrote: If you mean direct inject, that's what the two fronts are apparently. To be humbly honest, I've never heard that term. Alas the front of the Mbox is labeled "Mic/DI"
So, I guess the fronts are a free for all.
I was talking of DI boxes..
Here's an idea about levels you can find :
+4 dBu is "professional" line level, common in modern pro recording gear, and it is about 1.25 V.
0 dBv is an average line level, typical output from rackmount guitar/bass preamps.
-10 dBv is "consumer" line level, common with older and cheaper recording gear.
-20 dBu is roughly in the neighborhood of a typical instrument's output.
-30 dBu is again in the neighborhood of a typical microphone or DI box's output.
However, instruments and microphones can have a very wide range of output levels in reality, so it is most practical to think of instrument-level and mic-level in/outputs as just "a lot lower than line level", rather than calculating specific dB amounts.

If you plug the TD11 in a DI box, the DI XLR to a mic input, you should get better levels without adding noises (common of long unbalance/mono cables)
In any case, you may already have your recipe with the front mic inputs.

Did you consider recording the midi only and use a Vsti in the DAW ? Like Addictive drums or others..

Kurt Foster Tue, 11/01/2016 - 15:25
most all interfaces do not have dedicated line ins on the mic pre channels. it's a cost saving feature. i'd love to see an affordable interface with line only ins as i think the pres we get on most of these boxes are a compromise to be kind. the last inexpensive interface i found that had line ins only was the Alesis AI3. 24/48. no good.

kmetal Tue, 11/01/2016 - 16:39
The focusrite clarett 8preX has dedicated line in jacks.

Now I'm not sure if this completely bypasses the pre amp sections op amps or whatever else might be in the path, I'm not great w my understanding of Circuitry yet.

The review says the sound quality is pretty high for a project studio oriented device comparable to apogee and ua.

http://www.soundonsound.com/reviews/focusrite-clarett-8pre-8prex

I think your point brings up a very important issue a lot of us may not have considered.

The more I learn about these all in one interfaces the more I dislike them. They offer a lot of compromises to Some of most important parts of the chain the pre amp, and adda.

kmetal Tue, 11/01/2016 - 17:53
Kurt Foster, post: 442909, member: 7836 wrote: they always say that. o_O and again, it's thunderbolt. that means a new computer and not a cheap one.

Lol they do always say that. Sos in particular has a soft spot for focusrite in general.

New computer not necessarily. You can put a $25 pcie TB card in if you have an open slot. As long as it's the pcie x4 type which would be on anything 6 years or so or newer your in cheap.

Kurt Foster Tue, 11/01/2016 - 18:39
but you need the ram and the HD capacity to run it and you need a 64 bit system that means windoze 7 or better and if you go there you might as well update to the newest os and that means chasing bugs ..... lol. this is what i'm saying. it's a constant go round of new computers , os upgrades and then a DAW upgrade to take full advantage of the updates on the computer. by that time, there's a new and better interface on the market that will do everything except wipe your bum (or so they promise). meanwhile that MARA machine in the corner still works in spite of it being 30 years old.

kmetal Tue, 11/01/2016 - 19:47
Kurt Foster, post: 442914, member: 7836 wrote: but you need the ram and the HD capacity to run it and you need a 64 bit system that means windoze 7 or better and if you go there you might as well update to the newest os and that means chasing bug ..... lol. this is what i'm saying. it's a constant go round of new computers , os upgrades and then a DAW upgrade to take full advantage of the updates on the computer. by that time, there's a new and better interface on the market that will do everything except wipe your bum (or so they promise). meanwhile that MARA machine in the corner still works in spite of it being 30 years old.

Pretty much. It's pretty much a given that every 3-10 years your computer system and audio conversion will be completely replaced.

basically it's about 15k over that period assuming you've established a bassline of stuff.

To maintain a basic modest daw/converter setup is about 1-2k per year on average all (most) things considered. Start talking anything more than pro standard the number doubles or triples.

It doesn't seem like the trend is slowing either.

Last time I bought a setup was an 800 laptop and 500 interface. I used it for 8 years, and didn't upgrade at the 5 year mark when it really needed it cuz I worked at the studio.

Interestingly the Mics and speakers are worth about 80% or more of what I paid back then in '05.

It's a terrible business. I'm just s sucker for the best and biggest sounds. I'm a fan. For money im gonna end up doing some real estate or something. Or teaching or something. For fun, listening to tunes in a dark room is still amazing.

To me the worst part is knowing that your buying something that's obsolete because it is by the time it's released in most cases. That hurts. Lol.

But when you get a thunderous sound system in a good room time stops.

So is it a good business move nope. Practical nope. Worth it? For me it still is. I just don't connect w anything else.

Fortunately I'm good with numbers and there's allowances for whacked folks like me so I won't starve completely and I'll have a place to stay of my own.

Frankly I've invested fairly lightly and I've gotten about 3-4of the 8-10k I put in back. So it's certainly a financial loss, but I call it cost of entry. I've had some great moments w that old m audio interface and mackie HRs. Worth every penny from a fans perspective. Buieness wise, they barely paid for themselves if at all. Being a tech and consulatant and designer made the money.

I'm just chomping at the but to hear my VSL thru a 6 core playing realtime in surround. lol that's a 2k ball of fun. Completely impractical.

The speakers and Mics are places to safely drop big coin. Good quality speakers last decades.

Acoustics and speakers won't change significantly until we start employing new space age materials.

So fuck it. Damn right I'm putting a 15kw surround system in. It'll make me smile...

As for the computer. It'll be worthless in a year and I'll ride it till it chokes.

DonnyThompson Thu, 11/03/2016 - 01:26
Kurt Foster, post: 442914, member: 7836 wrote: but you need the ram and the HD capacity to run it and you need a 64 bit system that means windoze 7 or better and if you go there you might as well update to the newest os and that means chasing bugs ..... lol.
Well, yeah, except that most who are doing DAW production already have those things. You're the exception to this, Kurt. I'm not saying that to be a d i c k ... I'm just confirming what you've been saying about your computer rig all along.

No one who is serious about DAW production is using Windows Vista anymore, or using a single ( or even dual) core, 32 bit system with 4 gig of RAM and a 50 gig HDD.

Most are using 64 bit, 2.5 ghz (or better) quad-core cpu's, an HDD with at least 500 gig of storage, and running an OS of W7 or later.

For you, it's a much bigger jump to get current, because you stopped upgrading so long ago. ;)

Brother Junk Thu, 11/03/2016 - 14:18
bouldersound, post: 442984, member: 38959 wrote: By now someone should have asked what you are considering to be the right volume. What exactly is your idea of "the right volume"?
Well, the context is how loud the drums are, coming through the daw. So if I have to crank the brain output, and crank the track to +12db even to be heard, the volume isn't right. I think maybe no one asked bc they already knew how drastic the problem was (I mentioned it in another thread before starting this one).

I didn't measure it (the signal), but with the PT track cranked to +12db, the brain output lowered to "non-clipping" (it has a meter) I get 3 green bars in PT. That's plugged in the rear inputs with the -10db switch on. Which is the louder of the two, bc apparently that's based on the typical levels of signal from various gear. E.g. Pro Gear, might be at a +4, so it's more like an attenuation switch (am I making sense?) and the labels aren't the effect, it's what signal level is coming in? I'm sure you understand it already...I just learned it, so I'm sure I'm not explaining it well.

If I plug into the front inputs, I have the knobs, so with that, my volume problems are gone. The knobs are at like 11 o'clock and I stay just under clipping in PT.

Brother Junk Thu, 11/03/2016 - 14:35
Kurt Foster, post: 442995, member: 7836 wrote: i think you are doing something terribly wrong. you should not need to get anywhere near clipping in PT.

-18 (digital scale) roughly equates to 0dB Vu @ +4 levels, give or take a dB or two either way depending on the DAW program.
I'm giving him the best volume references I can. Nothing is terribly wrong.

Brother Junk Fri, 11/04/2016 - 08:44
Kurt Foster, post: 442997, member: 7836 wrote: are you saying you are not getting close to 0 dB in PT?
He asked about volume levels.

I haven't measured them, nor the signal coming in. So I'm simply trying to relate the volume levels I can achieve with each input and setting.

With the Roland TD-11's, plugged into the line inputs in the back of the Mbox Pro 3, attenuated to +4, it's inaudible. If I jack the PT track up to +12db I can hear something, but barely.

When I put the switch into the -10db setting, if the PT track volume is jacked to +12, and the Roland Brain also cranked, I get 3-4 green bars in PT.

When I plug into the front, and set the Roland's output safely below clipping, leave the PT track at 0db, and turn the knobs to about 11 o'clock, when I bang on the drums I still stay under clipping in PT.

I'm trying to describe to him what volumes I get with each method.

I think you are reading what I said as "this is how loud they should be run." When I go back and read what I wrote, I can see why you are thinking what you are thinking. But I'm just trying to explain (the best way I can) what volumes I get.

Using the rear LI's set to +4, and the PT track at +12db, I get almost nothing.
Set to -10, and the PT track set to +12db, I get 3-4 bars max
Plugged into the front with the PT track set to zero, the knobs at about 11 o'clock, it stays just under clipping.

For all intents and purposes, I could have said if I set to 12 o'clock I start clipping, or 10 o'clock and I get 8 green bars. I just chose maximum unclipped volume as the benchmark. I can't actually play them at that volume bc they would be too loud relative to the other tracks.

But you seemed to have a point you wanted to make, or something you wanted me to learn....if so, I'm interested regardless of the misunderstanding. How should I be setting my volume in PT? (I'm being sincere)

DonnyThompson Fri, 11/04/2016 - 09:25
Just to rule out every possibility...

Have you checked the Roland control device to make sure that you are sending the drums out to the outputs you are using? Or that you have the volumes on the Roland set for a decent level?

I guess I'm asking... are you sure that the Roland itself is sending out what it should be? Sometimes internal settings can be changed inadvertently; there might be individual drum volumes that need to come up in the Roland brain...?

Brother Junk Sat, 11/05/2016 - 06:37
DonnyThompson, post: 443021, member: 46114 wrote: Just to rule out every possibility...

Have you checked the Roland control device to make sure that you are sending the drums out to the outputs you are using? Or that you have the volumes on the Roland set for a decent level?

I guess I'm asking... are you sure that the Roland itself is sending out what it should be? Sometimes internal settings can be changed inadvertently; there might be individual drum volumes that need to come up in the Roland brain...?
Yes, I'm sure. I have the right volume now...it's all set. I spoke to another TD-11 user at Sweetwater (experienced though) and he said his are the same. He said it has to go DI, or Direct Inject. Granted, I'm new to all this, but I have never heard of that term. I think it's just a fancy way of saying instrument level vs line level. But here it is....page 19, Direct Inject (I learn something new every day) http://akmedia.digidesign.com/support/docs/Mbox_Pro_User_Guide_v90_69711.pdf

That's why DonnyThompson when you mentioned going to a DI, I thought you meant "direct inject." But it was just coincidence.

But for the sake of information, I looked everywhere in the Roland menu for every adjustment I could make. I can alter the kit volume from like 80-100 (iirc) the pad sensitivity is at 12 and can be bumped to 20, and the knob adjusts the signal out. I also changed the firmware, and did several resets.

The volume problem was the same, whether using the outputs or USB. I can adjust USB volume output from the menu too...but it has the same effect of putting me into the zone of clipping. The drums are fairly dynamic, so you need that headroom they give you.

So what happens when I do any of that is the drums start to clip. There is a small 5 bar meter on the brain screen, the last bar means clipping. So, it's pretty much setup straight from the factory, minus a couple personal adjustments. And the volume knob on the drums needs to stay at about 3 o'clock to avoid clipping too.

I think my main mistake was thinking the drums were line level out. They aren't. It's instrument level. I actually don't know why I assumed they were line level....it's basically an instrument. Noob mistake I guess? I'm new to this side of a studio. I've used them...but I paid by the hour to use, an already setup system. Setting up my own has come with some growing pains. I'm not used to setting up mics, and guitars, etc. I'm not a roadie....I designed speaker enclosures, and car audio, and home theatre. So, I have an idea of what I'm doing? Meaning, I'm not totally in the dark?

Here is a good way to explain it. You take a car audio system apart, and I could put it back together very quickly. I recognize all the parts, I know what they do. I know where they should go, I know what every cable does. I don't have that familiarity with studio gear. If you took a studio apart, and asked me to put it back together, I would do better than the average person off the street, but I would definitely be concerned that it was wrong when I was done lol.

I really like the drums. It takes a little getting used to, but I love that they are practically silent, and I can have 50 different kits with hardly any work. But the kick feels like a real kick, you can get used to the high hat setup, the tom rebound isn't bad. For $850, you can't go wrong. I think I paid $750 actually.

So, is "Direct Inject" a term you guys use often?

Brother Junk Sat, 11/05/2016 - 07:04
P.s. My question about the "Direct Inject" is mostly because the guy a Sweetwater asked me what equipment I had. I told him the Mbox Pro. So I'm not sure if he was just taking that term from a help sheet, e.g. It's a digidesign/avid proprietary term or if it's actually used universally and I've just never heard it.

My studio use was supplemented by my home use with a MBP, a focus rite scarlett 2i2, and a usb Novation Impulse. My only guitar is acoustic. So my "studio setup" experience basically consists of plugging in a Scarlett converter via USB to the MBP, and the Impulse, also via USB. The scarlett went to a pair of JBL LSR's with XLR cables.

I would set up and break down in my living room, every time I needed to work on something. So, having a permanent setup was my goal, and not having to plug/unplug stuff all the time...just turn everything on, and go!

So all the cables, and inputs, and sends and outputs...it's a learning experience for me. Half of my problem started bc I didn't know that I needed to use mono cables with the drums. Stereo does not work. I'm making dumb mistakes like that.

So I appreciate all the patience. I wish I had more to offer you guys.

bouldersound Sat, 11/05/2016 - 08:20
Brother Junk, post: 443019, member: 49944 wrote: But you seemed to have a point you wanted to make, or something you wanted me to learn....if so, I'm interested regardless of the misunderstanding. How should I be setting my volume in PT? (I'm being sincere)

The target level in digital is typically -18dBFS. I believe that's indicated in the channel meter by the transition from dark green to light green. For any signal that's more or less continuous the level should be crossing that boundary regularly. Percussion is different because it's usually momentary rather than continuous. In that case set the level by peaks, to about -12dBFS. Since there are no numbers on the meter I just make it go into the light green a bit, staying out of the orange. At no time (until mastering) should any level approach the top of the meter.

Brother Junk Sat, 11/05/2016 - 09:34
bouldersound, post: 443042, member: 38959 wrote: The target level in digital is typically -18dBFS. I believe that's indicated in the channel meter by the transition from dark green to light green.
Awesome!!! I will double check that, (if it's indicated by the color) but that's something I had never learned in my PT lessons.

So, what is the reason for the -18dBFS? When I submit stuff for iTunes or whatever, they will "re-master" it. I'm not sure if they still use that term. I'm pretty sure they are just setting volume limits etc.

Let's assume for a moment that there is no indication readily seen in the track meter in PT...is there a plug in or meter/monitor type thing to make sure I'm at the right levels?

DonnyThompson Sat, 11/05/2016 - 09:35
Brother Junk, post: 443038, member: 49944 wrote: I think my main mistake was thinking the drums were line level out.
Yup. There it is. Line levels are generally sent by devices that have amplifiers in them. Your drum module does not, and requires that the output signal be amplified up to an acceptable level through a preamp, and in your case, this would be using the instrument inputs ( DI's) of your audio i/o.

bouldersound Sat, 11/05/2016 - 10:16
Brother Junk, post: 443044, member: 49944 wrote: So, what is the reason for the -18dBFS?

If you keep your average levels around there you'll never run out of digital headroom. It's just the convention in digital to use the highest possible level, 0dBFS (full scale) as the reference point. The usual scale used in analog is VU, where the 0dBVU point is your target and you've usually got 12-24dB of headroom above. In most cases, depending on the converter, 0dBVU in analog becomes -18dBFS in digital. If your preamp has decent metering you should be able to set the analog level appropriately and end up with proper digital levels without even seeing an meters in the software.

Brother Junk, post: 443044, member: 49944 wrote: When I submit stuff for iTunes or whatever, they will "re-master" it. I'm not sure if they still use that term. I'm pretty sure they are just setting volume limits etc.

As far as I know iTunes doesn't permanently change your file but it does have a playback option to even out the volumes of different music files in a playlist. Either way, keep average levels around -18dBFS until mastering. Bounce your mix out at that level then import it to a new session for mastering.

Brother Junk Sat, 11/05/2016 - 12:06
DonnyThompson, post: 443045, member: 46114 wrote: Line levels are generally sent by devices that have amplifiers in them. Your drum module does not, and requires that the output signal be amplified up to an acceptable level through a preamp, and in your case, this would be using the instrument inputs ( DI's) of your audio i/o.

Perfect explanation, thank you. I get it now, and I don't think I'll ever forget it.

bouldersound, post: 443047, member: 38959 wrote: Bounce your mix out at that level then import it to a new session for mastering.
Ahhh....tricky!!!!!

And no, iTunes doesn't change the file. I'm pretty sure they just run it through some sort of limiter to get fairly even volume levels. The reason I wanted to know about the -18db was I figured the closer I was to their standard, the less they would mess with my product. But they used to call it "mastering." Maybe they still do, I dunno.

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