Here are a couple of good links

http://en.wikipedia.org/wiki/Talk:Audio_level_compression

even a humorist version at

http://journalscape.com/keithsnyder/2003-09-13-11:44

Hope these will help if not come back and ask some specific questions and I and others will try and answer them.

1. Different settings for different gear. And it isn't so much the mic that determines how much compression you want; it is the source you are recording and your own tastes for compression usage.
2. Software compression is much cheaper than hardware. Good hardware compressors cost thousands of $$$, but most will agree they sound better than software.
3. During, after, both, neither; It's up to you.

I think the best thing you can do is get a cheapy compressor (RNC or DBX or something) and just fiddle with it, read the manual, and so on. Or just spend some time fiddling with some software compressors and reading their help files. Hands-on experience is a must to understand compression.

macbodock wrote: I read the white sheet from dbx and well have no clue about what is said. Thats right I'm an old disk jockey and all this technical stuff is lost on me so forgive the stupid question(s).

"Spinning wax at parties" DJ or "You're listneing to KRAK, I'm Bones and THIS is the new one from Mother's Finest!" DJ? They each have their reasons to die, so I'm glad to see you're clawing your way up from the depths of depravity. Welcome to the light.

macbodock wrote:
1) Does settings change with the equipment you use? Different setting for diffrent microphones? Or is it just a general setting that is different with what you are recording
(can you tell I am lost?)

Yeah, I can tell. But no biggie, compression has brought many a big, strong man to their knees. What you've got here is the classic mistake of somebody who's read too much about compressors from people who don't use them often enough theirselves. For example, 99% of the people on this forum. Sorry to be blunt about that, but the "some compression to excite my dynamics" discussion really gave me a sad outlook on the local intelligencia.

The assumption I read from your question is that there are certain "settings" one can dial up on a compressor and that these "settings" (defined, I assume, as a set of positions for each of the common compressor controls) match up with either certain situations or certain other combinations of gear.

For example, I would imagine you expect it to be true that if you use an SM57 on a guitar amp playing heavy metal that you should use compressor setting group 621951-b which consists of attack = 8ms, release = 25ms, ratio = 4:1, threshold = -15dB. Which is absolutely untrue. Plenty of people will be here shortly to reiterate this, but compressor settings are variable per each use regardless of the source or, other gear involved with, or destination of the signal. However, all is not lost, read on...

What you need to effectively use compression are two things, one of which I can give you here. The other one you're going to have to get on your own.

Shotgun's Compressor Tools 1 of 2
What you have to do is understand what compressors do, and what each of the controls do IN GENERAL. Then you apply that knowlege to what you want out of using the compressor and what your ears hear AT THE TIME OF USE so that you can adjust as necessary. So, read below for an overview of the box as a whole and each knob you're likely to find on it.

Compression
From the name, one can surmise that a compressor is going to squish, squash, mash or pulverize something. Given that we plug audio signals into it, we can further surmise that what is getting squished, squashed, mashed or pulverized is, indeed, our audio signal. And one would be completely correct in assuming that. But what does that really mean?

Well, consider an audio signal. Let's say it's a recording of my mom yelling at me about leaving my laundry piled haphazardly in the hallway. First, mom starts out trying to reason with me, gently, "Shotgun, you know, it's just not condusive to laundry efficiency leaving that stuff piled haphazardly like that..." her voice is calm, even and even somewhat soft. As I stare at her blankly, not understanding the finer points of sorting one's laundry and transporting it to the appropriate room in the house her voice becomes stronger and louder. "SHOTGUN! I'M GOING TO BEAT THE LIVING SHIT OUT OF YOU WITH A TIRE IRON IF YOU DON'T PICK THIS SHIT UP IMMEDIATELY AND PUT IT WHERE IT BELONGS SO HELP ME GOD!" Now she's yelling, screaming, in fact. Her face is red and frankly, I've just soiled myself which makes the entire laundry issue even more complicated.

Now, let's assume we're going to lay this recording of mom over some Nine Inch Nails-style door slamming, pipe clanging, fuzz guitar backing tracks. It's going to be an artistic tour-de-force. However, when mom starts out, her voice was hitting only about 65-70dB--normal conversational speech. By the time she's done it's more like 105dB worth of banshee howling. Unfortunately, our backing tracks are a pretty even volume the whole way through. So, at the beginning of the track mom will be virtually inaduible whereas at the end she'll be drowning out my samples of whacking a stapler on a desk. How do we deal with that?

WE USE A COMPRESSOR!

You see, what a compressor compresses is volume. That is, technically, it compresses the amplitude of the signal, or its "gain". So for every decibel that goes into the compressor, only a fraction of it will come out. That means that (depending on our settings, see below) if mom's voice uncompressed winds up at 105dB then we can set our compressor so that it only gets as high as 52dB if we want. How does that help you ask? Won't it still be too low to hear over the backing music? Yes it will, but read on and we'll cover that in the controls discussion.

Threshold
The threshold control on a compressor sets a level below which the compressor will do no work. The control is graduated in dB (in this case dBV of signal level) and allows you to set an "on/off" point so that you can compress the LOUD parts of a signal, and leave the soft parts alone. At times you may want to set this control low enough so that you're affecting the entire signal, at times you may not. In the case of mom's rant-on-tape, what we may want to do is set the compressor so that it doesn't touch the signal until her voice reaches something like 85dB or so***, say, about halfway up the scale from softest to loudest. So, we set the threshold so that we only see activity on our "gain reduction" meter when the track gets to a certain point.

To USE the threshold control effectively, you generally need to use your ears. Have some idea, before you start, of what you hope to accomplish by using the compressor and set the threshold to capture the part of a signal you wish to do whatever that is to. In our example I want to lower the louder parts of my mom's tirade so I set the threshold to activate the compression at some arbitrary point in the track. I could have done it several other ways and the only way to learn which is best is to experiment and listen.

Ratio
This is the control that tells us how much signal comes out of the box relative to what's coming in. It is graduated in terms of a ratio (hence the name) of output to input. So, let's say we set the control to point at "2:1". That means that for every 2dB of incoming signal, we're only going to get 1dB of outgoing signal. Which means that at its very loudest, mom's voice isn't going to be nearly as loud as it was originally. Keep in mind that this ratio only applies to signals that meet or exceed the threshold setting. Any signal that is below the threshold just passes through as though the compressor weren't there (kinda).

To use the ratio control effectively you, again, need some idea of what you want out of your compressor overall. In our case I just need mom's voice to be more easily mixed in with the backing tracks so I just want it to be kind of even. However, I still want it to start softer and get louder, just maybe not AS soft at the beginning and not AS loud at the end. That is, still changing, just not as much.

Attack
The attack control tells us that, once a signal meets or exceeds the threshold, how quickly does the compressor put the smack down on said signal? The control is usually graduated in intervals of time, usually marked in milliseconds. So, let's say that I set my attack control to say 5ms. That means that when the signal passing through reaches the threshold I've set, the compressor waits an additional 5ms before it begins to reduce the amplitude (again, gain). This seems counter-intuitive doesn't it? I mean, we want the level controlled WHEN it reachest threshold, right? Not 5ms later. Well, there are reasons for slightly delaying the attack (and for that matter release) times.

To use the attack time effectively (and by now you should have seen this coming) you need to know what you want out of your compressor in general. Do you want the signal clamped down on fairly quickly? Or not? How do you know? This brings in one of the most important concepts of recording: attack and decay. Each sound has an attack and a release. Imagine hitting a drum (the easiest place to see this concept). You hear the sharp, immediately loud sound as the stick hits the head, but you also hear the sound gently fade away, also. That initial WHACK, that initial spike in amplitude is the sound's attack. Everything else is it's decay. Note that I use these terms in a "Shotgun" type of way and there are more correct ways to say this, I think, but I tend to, over time, develop my own language, so you're at a disadvantage.

So then, we can hear an attack in mom's voice, too. It's more subtle than the attack of a drum hit with a stick, or a guitar player's pick against a string, but it's there. And if we set our compressor's attack time too short, we will lose all the definition of the attack of the sound. Sometimes that's desirable, but in our case it is not. A very large percentage of how people perceive sounds comes from the attack. You must strive to preserve that unless it is your desire to purposely not. Therefore, be very careful with the attacks under your care. In the case of a vocal track, the attack of the voice will lend very much to the intelligibility of the track, so we do NOT want to destroy it. So, we may want a slightly longer attack time than 5ms here. But we can only tell BY LISTENING. LISTEN to the track, sweep the attack control back and forth and listen to what happens to the attack of the sounds. If it sucks, move the control. Don't look at where it's pointing until you're satisfied with how it sounds. Then only look for the sake of curiosity because that setting may never work the same way again. if you're using a plug-in make sure you allow ample time for the movement to take effect. Moving a plug-in's controls can sometimes not take effect for a full second or two after you move it so if you're sweeping it back and forth rapidly you'll fool yourself. In the case of plugins, make a move and pause until it changes. If it doesn't change within 2-3 seconds, maybe you didn't move it far enough.

Release
As you might guess the release control handles the other end of the signal from the attack. That is, when a signal drops back below the threshold, how long does the compressor wait to actually stop compressing. All the same counter-intuitiveness applies here as well. However, remember that the decay or "tail" of a signal isn't as important to the listener as the attack so you can get away with a little more here. Again this control is going to be graduated in units of time, usually ms. However, the numbers will be larger than the attack times. Sometimes up into the 100's of ms or even full seconds.

To set a proper release time, again, understand what you want out of your compressor. Do you want a major thrashing to your sound, or do you just want kind of a gentle corrective measure? What you have to look out for in the case of release times is pumping. If your release time is set too short then the sound will drop below the threshold, the compressor will release it, but the sound will then jump UP in level because the compression is no longer making it softer, but it's below threshold. That probably sounds confusing, but it happens. And it will sound pretty odd. The first time you hear it you'll understand why it's called "pumping". It sounds almost like there's a new "attack" near the end of the signal's decay. As I've said before, sometimes this is actually desirable. Usually it's not though. Your goal is to set a release time long enough to give the sound time to naturally decay to a point that when the compressor lets go it won't "pump" yet short enough so that the compressor isn't still active when the next "attack" comes along. If you set your release time too long it will start fucking around with the attacks because it's taking so long to let go the next loud signal is there before the last one is finished compressing. So, if you get your attack set where you think it's right, but then you start losing your attack again, consider dropping that release time lower (faster).

Make up gain
Here's where we answer your initial question of "Won't it still be too low to hear over the backing music?" Remember that we noted that mom's voice started out so low that it was lost in the music. And all we've done so far is to use our compressor to take the bite out of the louder part of the track so that it's not overpowering. So, doesn't this leave the softer part still lost? And, possibly, doesn't it make the WHOLE TRACK too soft now? Yes, it absolutely does. But that's what we have makeup gain for.

The makeup gain is going to look very similar to any other gain control you have seen. It will be marked off in dB, possibly starting at 0dB and moving up to some obscene amount like 20 or 40 or 60 or 100,000 or something. (It won't really be 100,000). The makeup gain does just what it says it does, too. It allows you to "make up" the gain that you're losing by compressing in the first place. Now, that doesn't mean it UNDOES what you just did, not by any means. It means that you can now take your newly compressed signal and make the WHOLE THING louder. This is how we're going to get the parts that are too soft up where they belong.

To set this control we're going to, of course, listen. What we've done thus far is to compress down the loudest parts of the signal so that they're not so loud. You can say that the loud parts are now "closer" to the soft parts so to speak. So what you do with your makeup gain is to take the whole lot and move it back UP some smaller amount so that now the loudest parts are just still loud, but not AS loud and the softer parts are still soft, but loud enough to be heard. Think of yourself playing basketball. If you're short like me, there's no way you can slam dunk a basketball. However, let's say you can lower your basketball goal by one foot. Now it's lower, but you still can't slam dunk it, but lowering it any more would ruin the rest of the game because you'd just be dropping the thing in and not shooting. So what you do is you make yourself magically grow a foot as well. Now the goal is still a reasonable height, but you can slam dunk because you've grown a bit yourself. Same sorta thing. Your signal isn't so low it sucks now, but it isn't so high you can't get anything useful out of it as well.

Here's a shocker: in terms of makeup gain there IS a general rule you can keep in mind. As you're setting your compressor's other settings you will notice the meter marked "gain reduction" giving you some idea of what you're doing to the signal. It could be a schitzophrenic little peak meter or it could be a big, slow, thoughtful VU meter. Either way it'll tell you "hey, you're getting about 5dB of gain reduction here pal!" So, this tells you you can START your makeup gain at a setting of +5dB. That should give you a compressed signal at the same general level as the uncompressed signal. Kinda. Sorta. It's a really ROUGH starting point, but it's a starting point nonetheless. Again, though, twist it and listen to get it where it really needs to be. You may want more, you may want less.

The BS you'll hear
Now, as you get replies to this thread there will be plenty of numbskulls along to give the following answers:

(1) Shotgun you're such a fucking asshole. The guy just wanted some basic info, some basic starting points for his compressor why do you have to be such a prick?

(2) Shotgun, you don't understand compression and you've never done any recording, HAVE you?

(3) Here are my basic settings and they'll probably work

None of that is even remotely true. Sure, there are plenty of basic starting points anybody here could give you. In fact, many of these folks have only been using compressors for about 6 months, but even THEY will have ONE setting group that they like for some reason and are DYING to tell you it in order to appear knowlegeable. Do not listen to any of this shit. Develop your own views on good starter compression settings by appying what you learn and what you hear and what you observe in your own experience. There are so many different kinds of compressors that anybody who gives you a rough setting diatribe is just pissing in the wind. In fact, many types of compressors don't even HAVE some of the controls I mentioned. Some have more. Also, there are plenty of points we haven't covered. For example limiting, which is a special kind of compression that uses a very high ratio (often infinity:1).

macbodock wrote:
2) Hardware compression or software. (why are software compression so much $$$?) Which should one use?

Software compressors are so expensive because it's a royal pain in the pussy to write that particular software. The stuff that a compressor does to a signal is ungodly complex. Not necessarily the "reduce gain by x when level reaches y, wait b ms and hold for r s.". That part is easy. The hard part is trying to model, in software, the "sound" of all the individual components of a compressor and how they interact with each other to product a "sound". You may be familiar with people talking about the "tube sound." Well, each electronic component is going to impart its own "flavor" onto the signal passing through it. Some compressors, in fact, are used not so much for compressing as they are for the mere sound imparted when signal passes through their components. For example, a studio I used to work at very often tracked vocals through an LA3 tube compressor set to very very low compression, hardly any audible compressing at all, just so that the vocal could pass through the tubes on the way in.

As to which of the two you use, well, it's up to you. One cannot say one way or the other is better without knowing many factors. Budget is one of them. There are several GREAT freeware compressor plugins available. Additionally, you may not have the facility to use hardware compressors effectively. It would require a mixing console, plenty of A/D and D/A and all the cabling and so forth to run a signal out of your DAW and into a compressor and back into your DAW (that is, I am assuming you're using a DAW since you ask about software compressors). On the other hand, many of the expensive, much sought-after hardware compressors have NO software equivalent and their "sound" can only be had by using hardware. (regardless of what that twit from Bombfactory says). The bottom line is that you should use whatever you can get your hands on because there's no such thing as too much experience.

macbodock wrote:
3) Add Compression during or after?

Again, a judgement call. I assume you mean during or after TRACKING. Because, if you use compression after you press a few CDs of a mix, it's not going to do you much good. As I mentioned earlier plenty of people use some compression during tracking. Sometimes that's for the actual compression, sometimes just for the sound of the compressor's components but hardly any actual compression. The cardinal rule to remember here is that you can ALWAYS add compression if you feel like you need it and didn't use it tracking. However, it's next to impossible to REMOVE compression if you used it tracking and later decide you don't like it. When in doubt, track as raw as you can and add stuff later. That's way easier than trying to make up for a bad compression choice in the beginning. Furthermore, as a beginner, you're probably not going to have a good enough handle on what types of compression are going to work for the mix as a whole during tracking to really make a good judgement. It would be a shot in the dark at best.

~S

***IMPORTANT NOTE: Please understand that the dBSPL of mom's voice is NOT the same as the dBV of the signal to which we are applying compression. If we knew what type of microphone was used, and what type of recording medium we could make rough calculations as to what dBV we would be working at, but we don't, so just suffice it to say that mom's voice was soft, then very loud and that the signal starts off weak and becomes accordingly stronger. Just don't make the mistake of assigning any particular significance to the numbers I'm using, I picked them at random.

oh, MAN.. this is an INSTANT CLASSIC.

Shotgun, I'm currently looking around the kitchen to find some Bounty(tm) brand paper towels to clean up the puddle that appeared in my chair as I read that.

I'm DYIN' here! Friggin' CRYIN' !

Not necessarily the "reduce gain by x when level reaches y, wait b ms and hold for r s.". That part is easy.

OMFG...that's TOO FUNNY!

The first time you hear it you'll understand why it's called "pumping".

Damn, I hate it when coffee comes out your nose like that...You owe me a new keyboard, Shotgun!

Just don't make the mistake of assigning any particular significance to the numbers I'm using, I picked them at random.

this is my new sig line!

(3) Here are my basic settings and they'll probably work

here are my settings: attack 0ms; release 3000ms; ratio: 50:1; threshold: -30db

I dont really no much about it but this setting always makes my trax better, u might want 2 try it anyways HAHA. Just thought it might help u.

Seriously, though, kids...school's in session. Take good notes.

dwoz

dwoz wrote:

(3) Here are my basic settings and they'll probably work

here are my settings: attack 0ms; release 3000ms; ratio: 50:1; threshold: -30db

I dont really no much about it but this setting always makes my trax better, u might want 2 try it anyways HAHA. Just thought it might help u.

Seriously, though, kids...school's in session. Take good notes.

dwoz

I can see we think alike! Although I don't usually use such a pussified ratio, but to each his own.

Oh, and this part:

"I dont really no much about it but this setting always makes my trax better, u might want 2 try it anyways HAHA. Just thought it might help u."

I bet'cha money we'll see a post JUST like that.

I dont really know much about it but this setting always makes my trax better, you might want to try it anyways ;) . Just thought it might help you:

Ratio 2.5 Threshold -38 Attack 50ms Release 250ms

TheRealShotgun wrote: [quote=macbodock]I read the white sheet from dbx and well have no clue about what is said. Thats right I'm an old disk jockey and all this technical stuff is lost on me so forgive the stupid question(s).

"Spinning wax at parties" DJ or "You're listneing to KRAK, I'm Bones and THIS is the new one from Mother's Finest!" DJ? They each have their reasons to die, so I'm glad to see you're clawing your way up from the depths of depravity. Welcome to the light.TheRealShotgun,
Thanks for the response I will get time to read it later. DJ of the radio variety. I worked at serveral stations including WAJI, WYHT, WFWI, WGL and WMEE.

Warmest Regards,

I'm probably going to 'sticky' this one as a service to the "99%" in the reference.

I'm also obligated to HATE you Mr. Shotgun for exposing me as the lazy bastard I am ....ie: Not spending enough time actually answering questions like this which would have an impact.

Language aside, its a very good description and for those who REALLY dont 'get it' about compression, please read it carefully and learn.

For those of you who think you get compression....good luck.

Its a thing that I have found is a bit fleeting in its grasp and bredth of scope. And I agree about the reason for this. Its never NEVER going to be the same setting....I dont give a Rats-nyyuks whether you have identical sources in an identical position in the identical studio.....It just doesnt stay the same.

As far as settings go.....shoot, I cant think of any....

Oh yeah now I remember why............

I never look at em......ever.

TheRealShotgun wrote:
There are several GREAT freeware compressor plugins available. ~S

ShotGun,
Thanks for a great reply! When I read the DBX white sheet on compression I thought what the f----? With the Shotgun compression sheet, I can say I get it more, not completly. I need to mess with compression in my DAW. Care to recommend any freeware compressor plugins? Dont need anything fancy and all the ones I've seen cost way to much $$$. I am using a macintosh so VST or Apple Audio units? Agan thanks so much Shotgun!

Warmest Regards,

:D

Greetings macbodock,

Try [[url=http://[/URL]="link removed[/]="link removed[/] for a wide range of commercial, shareware and freeware effects, processors & instruments.

HTH

Spy wrote: :D
Greetings macbodock,

Try [[url=http://[/URL]="link removed[/]="link removed[/] for a wide range of commercial, shareware and freeware effects, processors & instruments.

HTH

Thanks for the link. I will check it out when I have more time.

Warmest Regards,

Davedog wrote:
I'm also obligated to HATE you Mr. Shotgun

Heh heh, get in line buddy, get in line.

And I second your thoughts, anybody that claims to actually UNDERSTAND compression probably hasn't had it explained to them properly. (I stole that)

MacBoDock:
In addition to the KVR audio site provided, the free compressors that I would consider it a detriment to work without are found at:

(Dead Link Removed)

Both the "endorphin" and "blockfish" (part of the fish fillets package) are great plugins, in my opinion. They're free and I think all of them are available in both VST and AU.

Have fun.

~S

TheRealShotgun wrote:
MacBoDock:
In addition to the KVR audio site provided, the free compressors that I would consider it a detriment to work without are found at:

(Dead Link Removed)

Both the "endorphin" and "blockfish" (part of the fish fillets package) are great plugins, in my opinion. They're free and I think all of them are available in both VST and AU.

Have fun.

~S

PSSSST!!!!
Don't forget Spitfish.
Tame those pesky Esses.

And a whole different sort of compression usage. Just to confuse things further.

Oooo, and Floorfish is great too. OK, I'm done.

Thanks for all the help!

Thanks so much for all the info. Now it's up to me to learn what I can. You guys are great!

Warmest Regards,

Holy Crap Shotgun!

You just moved up a notch in my book. You answered a question with a DAMN fine explenation which had me laughing out loud.

I know - I'm still a mook in your book.

Some reviews for "Recording the Shotgun Way"........

Cucco wrote: Holy Crap Shotgun!

You just moved up a notch in my book. You answered a question with a DAMN fine explenation which had me laughing out loud.

I know - I'm still a mook in your book.

CoyoteTrax wrote:
You really have no experience in the field of recording at all, do you Mr. A$$Hat?

None, whatsoever. Can't you go play in a sandbox somewhere?

stickers wrote: Shotgun is a thread troll.

Your friend always and forever,

Stickers

ErikFlipside wrote: [quote=stickers]Shotgun is a thread troll.

Your friend always and forever,

Stickers

You mean asshole, right?

I think you meant asshole.

Jeeeeez.... shotgun this is a classic. :D , truly superb and funny :lol:

I still cant believe how you have managed to write a hole year of what i learnt at school in one forum posts...

But its fearly long thow! My eyes are sore!.

Made me laugh to :P Just to bad my english is less complete than swiss cheese.

DAMMMMM..... thats a master class, ony thing that I knew until know about compression was about the squishy part, now I understand it much better,,... I would have love to have a mom that did my laundry, , that would have help me ....

Thanks a lot Mr. Shotgun, :)

A great ramble Shottie.

Kudos.

SM.

Slipperman wrote: A great ramble Shottie.

Kudos.

SM.

I'm seriously humbled. Good to hear from ya Slip.

~S

new to this site - i have a question about compression and wasn't sure if i should put it here or somewhere else.

You can use compression to control overall level or to shape a sound. i.e - you can use compression to make all sounds more even, or you can use compression to lower the attack of a sound etc. my question is can you do both?

if i have a sound source that has a quick attack (e.g. - snare), and i want to even up the dynamic level of the track i can perhaps apply compression to it at 10:1 and it'll be level but then the attack of the sound is gone, so then you can adjust the attack to allow the attack of the sound to come through, but then the track isn't going to be level anymore cos the attack is the loudest bit of the sound and will vary dramatically from hit to hit. so how do you retain the attack but even up the level?

does this make sense? am i missing a vital part of understanding compression?

danna wrote: new to this site - i have a question about compression and wasn't sure if i should put it here or somewhere else.

You can use compression to control overall level or to shape a sound. i.e - you can use compression to make all sounds more even, or you can use compression to lower the attack of a sound etc. my question is can you do both?

if i have a sound source that has a quick attack (e.g. - snare), and i want to even up the dynamic level of the track i can perhaps apply compression to it at 10:1 and it'll be level but then the attack of the sound is gone, so then you can adjust the attack to allow the attack of the sound to come through, but then the track isn't going to be level anymore cos the attack is the loudest bit of the sound and will vary dramatically from hit to hit. so how do you retain the attack but even up the level?

does this make sense? am i missing a vital part of understanding compression?

Well, I'd say that to begin with, if you've got a snare track that has a 10-to-1 difference in hits across the track then your problem originates with your drummer, unless he did it on purpose. Is this a jazz track? Best way to solve a drummer problem is whack 'im in the head with his own cowbell and tell him to play like a man.

However, if this track exists and the only thing you can do is march forward and be a trooper, then compression may or may not be your ideal tool. Try it, but it might not be the whole fix, or it might not even be any of the fix.

First, like I said, listen to the whole cut and see if the snare dynamics have a place or not. It may be that in the context of the whole song those dynamics make sense. Or, they may not.

Wherever you find a ratio you like (and you may want to try a lesser one than you mentioned to see if you can get acceptable results), you're going to have to make love to that attack knob to get it right. Remember that if you're using a compressor plugin on a DAW that you have to set it and wait a second or three before you hear the change sometimes. Don't get too antsy. Also maybe raise your threshold a bit so that it only grabs the very top of the peak. Then use your makeup gain to even up everything.

Then again, like I said before, maybe a compressor isn't your best tool. Driving screws can be DONE with a hammer, but it's easier with a screwdriver.

Maybe try some automated (or even manual) fader moves to get the snare hits more even in volume. Also, using some EQ can actually have some effect here too. Say you've used some fader moves to even things up fairly well, but you've still got a couple hits that stick out, yet when you pull their volume down they don't sound right. Try kicking some EQ on those hits, like maybe notch out something around the 3kHz neighborhood. Just those hits though. That means automation again if you're in a DAW. Or just quick fingers if you're not and don't have console automation.

If you do end up back at the compressor, keep in mind that plenty of compressors have a setting for automatic attack and release times (plugins too). Try kicking that on and see if it helps. Maybe also try a different compressor altogether, they all sound different.

Lemme know what you come up with.

~S

I have a solution to your volume differences. Or at least it worked for me.

I was mixing a kids choir and I'm being nice if I say there were MAJOR issues regarding timing, and wild variations in volumes of the various bass/drum hits.

But all was not lost, you see, my instrument is guitar and...well...to be blunt, I suck at it. But the benifit to that is that I have become a bit of a wiz at editing. It's not something I'm proud of, but one does what one can with the cards one has been dealt.

Anyway, this saved the tracks for me

-select the track
-go to "detect silence." Or at least that's what it's called in Cubase. This slices the track up into individual bits
-while they're all selected, 'Normalize." Each hit is now normalized to the exact same level, instead of them all just being brought up by the same amount.

Ta Daa, 900 snare shots, EXACTLY the same volume. Now they may sound a tad different, because they were hit differently, but it's a hell of a lot better than it was. Now you can compress in predictable way and not have to worry about automating the track level anyway. One less thing to worrrly about.

Once they're sliced, you can quantise them too, but it's really tricky to make it so you can't tell in the end, with drums anyway. Getting a real drummer is ultimately the way to go.

Thanks for the great info on compression.

At the risk of feeling the wrath, I'm going to ask what my be a dumb question.

I now understand there are no presets. I say that every morning as I sit on the floor with my legs contorted behind my neck: "ooooommmmm...theeeeere aaaaare noooooooo preeeeeesets"

My question is this: Is there an ORDER, in which one goes through the knobs, a twisin' and a tweakin'? As in, "always start with threshold," or "Make sure you always set the release last," or something like that? Or maybe not.

Thanks
Keith

P.S. Shotgun lives with his mom? Yeeesh, I'm a little creeped out now...

took-the-red-pill wrote:
-select the track
-go to "detect silence." Or at least that's what it's called in Cubase. This slices the track up into individual bits
-while they're all selected, 'Normalize." Each hit is now normalized to the exact same level, instead of them all just being brought up by the same amount.

WOW that seems like a great trick!! Has anyone else tried something like that?

Just wondering:

Is there any point really to use software compressors DURING tracking? I have heard some people using this to control the peaks (of loud vocalists often) but isn't that just fooling yourself? Should the compression with this goal in mind not take place before the A/D conversion (i.e.: you need a hardware compressor for this)?

I think you're better of using software compressors after tracking! But maybe I am missing something here and if so I am damn curious as to what!!

i read the first post to this and i know why you are confused my goodman, because its a dbx manual youre reading. when i read the dbx stuff i was totally confused as hell too. but compression isnt that complicated. first of all get a good compressor like something optical for starters, something similar to the la-2a. those are first and formest simple as hell to use, just gain and peak reduction. not to mention the good ones are usually tube. if you cant afford that go with the transistor based 1176, cause Urei owns the market for compressors, only difference between limiting amplifiers as opposed to opto-cell compressors is they work like an effect pedal. the attack and release is just how fast the compressor turns on and how fast it turns off (when a high peak occurs.)

you can mess with the ratios until you get what you want, but obviously good compression isn't meant to be heard. when you are fixing your music then yeah you can hear some stuff, but just a basic compression to fit each instrument into the mix at an equal level isn't really meant to be heard. the ratio is just for every 4 decibles that come in only 1 gets out, 20:1, 8:1, infinite:1 all button mode.

when you do that you will sometimes have to use more output gain. also if you turn the attack completely to 0 or off, the compressor acts as an amplifier, so you can use it to fix certain frequency waves.

and no i personally dont believe there is much point in using a compressor or any other dynamic processing during recording. just use your preamps. besides for most project studios to use dynamics during recording would require numerous compressors and equalizers and that just gets pointless. not to mention to record live with a band would require many more microphones, and a room for each musician in my opinion to be isolated. which in turn requires a bigger board. oh yeah and more preamps. more everything.

liquidstudios wrote: if you cant afford that go with the transistor based 1176, cause Urei owns the market for compressors, only difference between limiting amplifiers as opposed to opto-cell compressors is they work like an effect pedal.

Actually they are currently in the DJ mixer market....
http://www.ureidj.com/

Shotgun thanks for this post.

On the other hand too bad that you had to write it.

COmpression is a very sofisticated part of the audio world. Doeasn/t mean it's nasty or it has to eb hard to understand, but it needs respect.

I guess you wrote it because of all the stupid questions about preseting the compressor not how they work but how should it set it so i can get over the compression part ASAP.
It's a process (making love to atack button....) that some jsut dont figure out. Too bad.
What shot gun wrote is almost manual like. Examples you wrote so true. And very aplicable.

I would really like to talk more about compression.
Serious ...

Instead of kids asking what
-ratio is better for when tracking a bass 4:1 or 3:1, or
-is -30db treshold for female vocal ok,
-or which compressor should my daddy buy me
SSL, Urei or Drawmer....

i would like to know your expiriences/insights/suggestions about compression.

-on how making double bass a bit firmer.Not the exact settings you use but some tricks... E.g track it with an old telefunken and compress the hell out of it through the attack time
-i really like the opening track of MAnson's Holywood. It is said that the drums are miced mono and the soundn is really achieved with careful micing and huge compression. Any ideas how they did it? e.g long attack time tube compressors, high ratios, and why do you think so?

I see compression also as a psychoacoustic part of mixing process. something you should really get spiritual about. what helps you a lot, what separates good mixes form. bad. Any presets that actually woould work are of no interest to me, because Shotgun explained they vary from sound surce/equipment/musician.....

So people please stop asking stupid question and lets have serious talk.
The ideas behind using the compression, not how the knobs should be set when tracking a 6-part drum set.

We all read books ,interviews, ... of engineers/producers....
There is no right or wrong way to use equipment.
Only expiriences. Some have none, so lets start there...

I love the quote in 'Mixing with your mind':
Its not how loud you get the sound, its how you make the sound loud.

Shotgun dont get me wrong.

Thank you for writing the post.

mat

If using a compressor reduces the frequencies, maybe it should not be used for music if you want to keep the dynamics. However, for radio it is fine. For instance Howard Stern is always saying 'give me more more compression' to the engineer. For him, it means that he does not have to talk as loud, since he is doing it for five hours.
For singing, the singer should learn to move back as he or she raises the voice. Some frequencies are only present when a voice gets louder, the overtones from the false vocal cords. Tuvan throat singers make use of these folds to sing multiple frequencies at once.
If you got the chance to record them, a compressor would be counter productive.
Radio stations compete with each other on the dial by using compressors, they want people to stop on the loudest station. It is insanity.
Sirius does not need to do that, which is great.

oh wow my brain hurts . greatful for the info, and explained in laymen's terms--absolutly wonderful. :!:

Wow. A post for the ages, Shotgun! I love your colorful analogies.

And for the sake of further understanding of the less technical nature, I've been sharing this link as much as possible. Something for every engineer to think about.

http://www.rollingstone.com/news/story/17777619/the_death_of_high_fidelity

BluesDimeBag wrote: If using a compressor reduces the frequencies, maybe it should not be used for music if you want to keep the dynamics. However, for radio it is fine. For instance Howard Stern is always saying 'give me more more compression' to the engineer. For him, it means that he does not have to talk as loud, since he is doing it for five hours.
For singing, the singer should learn to move back as he or she raises the voice. Some frequencies are only present when a voice gets louder, the overtones from the false vocal cords. Tuvan throat singers make use of these folds to sing multiple frequencies at once.
If you got the chance to record them, a compressor would be counter productive.
Radio stations compete with each other on the dial by using compressors, they want people to stop on the loudest station. It is insanity.
Sirius does not need to do that, which is great.

I can't begin to tell you how much I disagree with this point of view. Radio compression is necessary because they have limited bandwidth and HAVE to compress the signal in order to get it out there. Sure mic technique is important, but damn. If you don't have something USEFUL to say, go say it at harmonycentral. Howard Stern? Really?

i suggest getting a copy of the recording engineers handbook

I smell something whiffy, some sort of packaged meat or meat-based product?

Ok...bluesDimeBag has demonstrated a "fundamental misunderstanding" of compression. He understands that compression is used in radio, but doesn't know what, how, or why, and so, let's help him, shall we?

...radio stations DO use compression, on ALL of their signal. Why? it has to do with two things:

First: the law. The radio station has a license to broadcast on a certain frequency(center), and at a certain maximum power. If they go over their rated power, then they get fined. If they go significantly under their rated power, then they are broadcasting to a significantly smaller area, thus a smaller listener base.

Second: perception. As you flip the dial, you are drawn to the stations that have a clear, strong signal. Most certainly, the "seek" button on your car stereo is convinced that the clear, strong signal is the one to stop on.

Ok, I lied...Third: listener environment. MOST radio listeners are in what we would characterize as a "disadvantaged" environment for listening...in a car...or, the radio is on as background...like at work.

In each of these situations, the radio station compressor helps to do something to the program material...it CHANGES the relationship between the "average amplitude" and the "peak amplitude". Specifically, by lowering the peak amplitude (i.e. 'compressing' it), it changes the standard deviation from the average amplitude, makes it smaller.

So, for problem 1...the station can bring the average level up, without the peaks going over their licensed power rating. For problem 2...the higher average volume makes the station "sound louder" than the other stations around it on the dial. For problem 3, the signal remains intelligible against the background noise in the listener's environment. Also, because the average sound level is higher, the nominal signal-to-noise ratio is improved, for the transmission chain.

When Howie Stern calls for more compression on his mic, that's a different thing. His mic technique is to get very close to the mic, and take advantage of the PROXIMITY EFFECT that boosts the bass on his voice, and to do so, he has to speak fairly softly. This does two things....first, it makes him sound rich and full...and second, it makes his delivery more "close" or "intimate". Using a mic this way results in a lot of variation, however, and the compressor is needed to smooth things out.

dwoz

So...shotgun has impeccably addressed the "what" of compression...what is it?

Now, let's get started on the "why".

Why use compression, within a mix?

Two main reasons.

First...to bind, or "glue" mix elements together.

Second...to separate mix elements from each other.

Third...to fix deficiencies in the mix element.

Number three is easy to understand. You have a bass part or singer with a fair amount of amplitude variation, where the desired effect is to have less variation. Applying compression will help to smooth out those variations. Or, you want to add some "body" to the part...a common technique is to take a parallel copy of the part, run that through a compressor, hitting quite hard, and bring that parallel track up along with the untouched track. (might need time-alignment). Such a technique leaves the peaks intact, while also raising the apparent "body" of the track.

There's a hundred more techniques like that.

For the FIRST point..."gluing" parts together...people will often bus several parts together onto an aux bus, and apply the compressor to the bus. This makes it so the compressor is responding to the overall level of both(multiple) inputs, and is compressing all inputs based on the most dominant (or "peaky" ) input. Net result is to tend to put all the elements included on the bus in the same sonic space.

The MOST SECRET and amazing use of a compressor, is to SEPARATE mix elements.

Let's go there.

Sidebar: you're looking at a photograph, a very nice photo, well composed, well exposed, well printed, well lit. In a gallery.

You notice something about it. The photograph has a characteristic "depth of field". The elements in front, close to the lens, are in sharp, crisp focus. The highlights are stark, the shadows dense. As you move "farther away" into the background, you note that the focus gets less sharp, and the highlights and shadows tend more toward grey. This is also an atmospheric effect, not just a lens effect. The air itself diffuses distant elements.

Now, surprisingly enough, the exact same principle applies to DEPTH OF FIELD in a music mix.

mix elements that are up front are detailed, crisp, with high dynamic range.

Mix elements that are away in back are softer, less transients, and less dynamic range.

Try an example? ok. Take a song that you're working on, and take two lead vocal takes. the best two...take 3 and take 11. bring them both up, pan them at 9:00 and 3:00 (i.e. a little away from each other to either side). level match them as best you can. Now, on take 3, apply a compressor, where you use a LONG attack, and a fast(ish) release. Go for a 10 db threshold, with a 2:1 ratio. Now, over on Take 11, set a VERY FAST attack...like, 0. set a slow release. set the same threshold and ratio.

Now, listen. I will bet you ANYTHING, that the fast attack take sounds farther back, and the slow attack take sounds in your face. pan them back to center, on top of each other. Hear the separation? Now, bypass the comps, and listen...hear the separation go away? Now, treat the "background" take with a very tiny amount of delay or just a TINY touch of reverb.

Wow.

You're used to using WAY more reverb than that, to get that "depth" thing going...

To recap....dynamics processing can affect the perception of DEPTH OF FIELD. things that have less transient attack are perceived as being farther away. Things that have a little high end rolled off sound farther away. Add it all together, and you have a soundstage.

dwoz

Mr Dwoz, thanx for yet another succinct and seemingly effortless post on music production realities.

Good to see ya around these parts.

Thanx for sharing.

Readership.....of course hes 100% correct.

Dwoz / Shotgun,
Thanks for those nuggets of wisdom. Your depth of field explanation was a real eye opener for me. I think it is really cool that there is a few of you experienced guys out there willing to share their experience with us.

This may be outside the scope of this thread, but I often wonder about the different compressor types like the FETs or Vari-Mu’s, etc. Do they have a sonic character that pairs them with certain instrument types or task. People are always talking about a Fairchild on the 2-bus, SSL on the drums, or a LA2A on the vocals. Rules of thumb or nostalgia?

I do realize that the bottom line is run what ya brung and use your ears creatively to get the job at hand done quickly with the best possible quality.

There's an encyclopedia brittanica's worth of material to cover in that question, so I'll just address a couple of general points.

First off...a question. Why do you use different mics on different sources? Why not just pick one very good mic, and use a lot of those?

The answer is a little more complex than "certain mics are better-suited to certain sources", and as simple as "because they sound different".

Think about it. A certain microphone has it's own particular "sonic signature". Even high-priced measurement mics. So, for a couple or three tracks, no big deal...but let's say you use the same mic on 14 different sources, all combining into one mix. the problem is, you start multiplying that sonic signature in your mix! it isn't just freq. response either. Transient response, how "fast" the mic capsule and electronics are...whether there's a lot of hysteresis (or not).

And when you get that "sonic signature" buildup, you can find yourself struggling against it.

The same phenomenon happens with mic pre's ...one of the reasons for "boutique" pre's, is to break up the monotony of using only the console pre's...not because they sound particularly BETTER, but more because they just don't sound exactly the same! and next to the summing bus, the mic pre's are a major component of a console's "sound".

There's times that you WANT the same sonic signature...like in stereo pair situations...but...

anyway, compressors are different than most other pieces of audio gear, because they seem to impart more "self-sonic-signature" to the programme than most other types of signal processors. In fact, you'll hear anecdotal stories of how so-and-so runs his mix through an 1176 just to impart some of that mojo...with compressor settings that won't do anything.

Because of this, it's a good idea to mix them up a bit, brand-for-brand, type-for-type.

Consider it like garlic (I'll digress into the 7th deadly sin of forum posting...using a cooking analogy). A little garlic is fantastic, but keep adding teaspoonfuls, over and over, and well....that's a bad analogy, because you simply CANNOT have "too much garlic".

Let's pick "oatmeal" instead. great stuff. can't get enough, really. But enough "oatmeal" in a mix is DEFINITELY too much oatmeal. You should never have "enough" oatmeal.

Unfortunately, the final answer to your question is, "It's mostly about taste". Generally speaking, units with a lot of "personal color" are ill-suited to be mix bus compressors. But, in a given situation, that may be just the thing.

It's decidedly less of an issue with software (plugin) comps...but the issue doesn't go away. Especially if you're using an "emulation" plugin...one that's TRYING to sound like the real hardware. Most often, they don't really achieve that, but they often DO achieve coloration.

dwoz