Compressing - basic questions (3 Viewers)

[coast to coast]

I've known for ages basically what compressing is (or at least thing I have) but because I've mainly been recording scrappy four track demos its been very important to me.

So compression - effectively making the quiet bit slightly louder and the loud bits slightly quieter, right? Over-compressions leaves everything the same and maddy sounding which is a bad thing I've gathered.

Furthermore I was reading my Tape Op book of interviews and some guy was basically explaining that analog tape often sounds good because there's a natural compression in built in tape recording, hence the warm sound and so on and that you "really need to learn how to use an outboard compressor with digital"

I'm at the moment using audacity to get my recordings on the computer. Is its compressor any good or does it make a difference what you use?

And what are good parameters to go by if you want to get a slightly warmer sound but keep the dynamics of the piece?

 

[Beanstalk]

I'm at the moment using audacity to get my recordings on the computer. Is its compressor any good or does it make a difference what you use?

Different compressers use different algorithms to do the job, so it does make a difference which brand/VST/RTA you use...some sound better than others.

And what are good parameters to go by if you want to get a slightly warmer sound but keep the dynamics of the piece?

Its personal taste, and depends on how dynamic the piece is before compression anyway...just tinker with the parameters, and see what sounds good to you...if it sounds too squashed, you've gone too far with your threshold or ratio.

You can get some tape emulation plug-ins like PSP Vintagewarmer, that might be what you're after.

 

[Pantone247]

Different compressers use different algorithms to do the job, so it does make a difference which brand/VST/RTA you use...some sound better than others.

Optical compressors are 'generally' considered to be more 'vintage' sounding, they're a little slower on the uptake and pump a little more audiably (I think) I think all the Joe Meek compressors are Optical so they'd be good to look at

Also the Blockfish compressor, which is a free VST from Fishfillets plug ins (yr going to have to google for it) is very good, I consider it "vintage" sounding on certain settings, i.e. it can be agressive and quite noticable

 

[coast to coast]

Okay. More stupid questions. Whats the difference between this and mastering?

 

[RED(tape)MENACE]

Audacity does VSTs now, right?
Grab the Kjaerhus Classic series of free plugins, the compressor is ok.
Blockfish might be a better place to start though, since it's got pretty minimal controls.

 

[Pantone247]

Okay. More stupid questions. Whats the difference between this and mastering?

compression is something you would do on individual tracks to reign in the dynamics, or give something a certain sound, sometimes you may compress an entire mix for the same reason... Mastering is basically a whole other process and should be thought of as the final stage of recording (or rather producing an professional song for public consumption) after Tracking and then Mixing and then Mastering...

http://en.wikipedia.org/wiki/Mastering

"Mastering is the process of preparing and transferring recorded audio to a medium that will be used in the production of copies"

 

[Lord Damian]

i think traditioinal wisdom holds that you should generally just use compression when tracking if you have to, but try not to use it when mixing (or at least try not to compress your final stereo mix). the mastering house will apply their own compression, which quality is usually leagues beyond what can be found in your average home or, indeed, commercial studio.

 

[coast to coast]

Cool. So when I've been compressing entire mixes and they sound shit its not suprise - I should be focusing on individual tracks. I'm gonna have to figure out how to get individual tracks onto my computer from my 8 track before I do anything!

Would this be a job for Cubase or something? I have it but no idea what it does.

Fuck, I think I've got a shit-load to learn...

 

[Lord Damian]

Cool. So when I've been compressing entire mixes and they sound shit its not suprise - I should be focusing on individual tracks.

Fuck, I think I've got a shit-load to learn...

we'll learn together. awwwww....

actually i'm just learning this stuff now as well, am heading in to record a couple of my bands for some demos, as well as another one in a proper studio, so i'll be watching this thread with interest, to teach me what to do with the limited equipment i have, as well as to have ideas for the studio situation...actually, this whole forum is great for the info.

 

[Lord Damian]

Cool. So when I've been compressing entire mixes and they sound shit its not suprise - I should be focusing on individual tracks. I'm gonna have to figure out how to get individual tracks onto my computer from my 8 track before I do anything!

Would this be a job for Cubase or something? I have it but no idea what it does.

Fuck, I think I've got a shit-load to learn...

PLUS - i'm having the same problem getting MY 8 tracks into the computer as well. let me know what you find out, so far have had no luck (the motherfuckers at Long & McQuade here in Toronto sold me some piece of shit that doesn't suit my purposes).

 

[coast to coast]

My 8 track was a pressie from my brother, so I'm not in a position to criticise it. Nor would I. I've found it quite good since I gave up my bizarre fetish for out of time, out of sync, muddy, overloaded unlistenable four-track cassette demos. Not that they are entirely charmless, but there comes a stage when we all have to grow up.

I bought the Tape Op book I mentioned in the first post in a Toronto record store. Its pretty useful (its a magazine as well) but they do have a tendency to talk as if you know everything about the subject already. Added to my tendency to not read instruction manuals, I become a slow learner... ugh.

 

[coast to coast]

AS the 8 tracks, I've been putting them in mixed from the 8 track and recording them as a WAV file on the line in. Not very scientific nor does it leave me with much scope for manipulation.

I'd also be intrigued if anyone could help me figured out how to sync up the drums I program on reason and the digital 8 track itself. At the moment I'm recording the programmed drums as sound rather than MIDI, which makes them uneditable later on...

ugh.

 

[Beanstalk]

I'd also be intrigued if anyone could help me figured out how to sync up the drums I program on reason and the digital 8 track itself.

What is the model/make of your 8 track?

What type of output connections are on it?

 

[coast to coast]

its a BOSS BR 864

has a standard line-out (red and white cables)

Digital Out, with a strange plug that I don't recognise, small, almost rectangular but the bottom corners are snipped off, if you can imagine that shape.

And MIDI Out

And a USB but thats for backing up recordings on the puter I think rather than an audio option.

 

[Beanstalk]

its a BOSS BR 864

And a USB but thats for backing up recordings on the puter I think rather than an audio option.

USB port...class...I wish I had one of those on my old Fostex.

Since there is a MIDI out it should be easy to sync with your puter (but you need a MIDI port on your puter, obviously).

To be honest, I'd use the USB to transfer the WAVs to a puter and use Cubase, Protools, Garageband or whatever, to mix your recorded WAVs and your Reason tracks (connected through Rewire). You don't really want to be mixing on the Boss. Pain-staking.

If you need your Reason tracks for the recording process you could always transfer a stereo mix over to the Boss temporarily as a guide track...using the USB or line in...whichever works.

 

[schmegeggin]

the only way to really get to grips with compression is to experiment with it.
interesting article on it
sound on sound on compression
also a FAQ i found on the net in the following post as thumped wouldn't let me post more than 10000 characters in the one post (also it wasn't compiled by me)

 

[schmegeggin]

COMPRESSION FAQ
Disclaimer: this is what I know about compression. I've done a lot of home recording, but I'm not a sound (or electronic) engineer so there may be inaccuracies. If you find something you disagree with, mail me at [email protected]

What is compression?
Compression is a process by which the difference in loudness between the loudest and quietest parts of an audio track (live or recorded) is made smaller.

The basic concept of a compressor is as follows: up as far as a certain level (the threshold), changes in the volume level of the input produce correponding changes in the volume of the output. Above the threshold, a changes in the volume level of the input will produce smaller changes in the level of the output.
With the make-up gain (more about that later) set to zero, once the input signal is lower than the threshold the output will be the same as the input. If the input goes, say, 8dB over the threshold and the ratio is set at 4:1, the output will only go 2dB over the threshold (the ratio is the ratio between changes in input level and output level once the threshold is exceeded).

So, essentially, what a compressor is does is make the louder bits quieter. Obviously this means that the output from the compressor will be quieter than the input. You can counteract this using the make-up gain, which is just an amplifier, making the output louder. So, as well as making the loud bits quieter, you can make the quiet bits louder (by making the loud bits quieter then turning up the whole lot so the loud bits are at the same level they were before ... hey presto, the quiet bits are louder).

What is gain reduction?Gain reduction is just the difference in level between the output and the input. In the above example (input 8dB over the threshold, ratio of 4:1, therefore output 2dB over threshold), gain reduction is 6dB.

What are attack and release?
Attack is how quickly the compressor begins to act after the threshold has been exceeded - the length of time it takes the electronics in your compressor to realise that the input has exceeded the threshold and start reducing the level of the signal it's sending to the output.
Release is the reverse - it's the length of time between the input signal falling below the threshold and the compressor stopping its attenuation of the signal it is sending to the output.

How do the controls on my compressor correspond to the above?
Threshold, ratio, make-up gain, attack and release are the basic compression parameters, but they might have different names on your particular machine or be marked differently, or they might even be missing. Some basic compressors that you might find say on a bass amp just have one knob that says 'Compression' - this probably controls threshold (with ratio, make-up gain, attack and release all fixed). In this situation your best bet probably just to twiddle the knob until it sounds good.
Threshold units are usually dB, and will run from minus some number to zero. Basically a lower number (ie bigger minus number) means the threshold is lower - -24dB means the compressor will kick in sooner than -6dB. It's possible that threshold could be marked 0-10 - in that case I'd guess that lower numbers correspond to a lower threshold, but it's conceivable that it'd be the other way around, depending on the machine.
Make-up gain can be marked in dB (from zero up) or 0-10, bigger numbers means more gain.
Ratio is easy to spot, it's a ratio (2:1, 8:1, 100:1 or whatever). I have also seen it called 'slope' - in this case a steeper slope would presumably mean a lower ratio.
Attack and release can be difficult to figure out - sometimes they are marked in time units (smaller number=faster attack), sometimes just 0-10 (higher number=faster attack? ... only way to tell is to play with it), sometimes just 'fast' and 'slow'.

What would I want to use a compressor for? 1. Compressing!
The most simple use of a compressor is where there are big variations in volume in something you're recording (or mixing, or putting through a PA) - on the loudest bits you're getting distortion, but if you turn it down the quiet bits are too quiet. You need to make the loud bits quieter relative to the soft bits, so you set your threshold so that the loud bits trigger compression, then set your ratio so that you're no longer getting distortion. If the quiet bits are still too quiet, turn up the gain a bit, then maybe turn up the ratio to take a bit more off the loud bits. You'll want to have your attack set quite fast, cos you want the compressor to kick in before the signal gets loud enough to cause distortion.

2. Adding punch
You can also use a compressor as a kind of an effect. Set a low threshold with a fairly high ratio so that more or less any input signal will be squashed, then set a not-so-fast attack. Because the attack is a little bit slow, the start of a input sound gets past the compressor, then the compressor kicks in and reduces the gain. This emphasises the start of the sound, and can add 'punch' to percussive sounds like drums or ska guitar or picked bass. You might want to use a second compressor with a higher threshold and fast attack to keep all the 'punches' around the same level.

3. Making things louder
There's a limit to how loud a sound on a tape or CD or piece of vinyl can be. For your recording to be as loud as everyone else's, you'll want to try and make sure that the loudest sound on your recording is getting close to that limit. However, if the loudest sound on your recording is a lot louder than everything else, you might find that everything else seems too quiet. You can use a compressor to make the loudest bits a bit quieter, then crank up the make-up gain to make the loudest bits approach the limit of your tape/CD/vinyl/harddisk again and hey presto your recording is LOUDER. Don't go too overboard on this though, it's fairly easy to compress something so much that is no longer sounds musical - your ears and brain expect variations in loudness, so if you've compressed something so much that there's none, it's going to sound odd.

Note that the particular settings on your compressor will vary not only with what you want it to do, but with whatever it is that you're compressing. A very fast attack tends to distort bass, and compression affects the sound (no matter now 'transparent' the manufacturer says your compressor is), so you'll probably have to fiddle with the setting for, say, a vocal so it doesn't sound too unnatural.

When would I NOT want to use a compressor? If you plan to get a recording mastered, it's not a good idea to compress the mix as a whole (compress away on individual tracks). It's likely that the mastering engineer has much better compressors than you, and if you've already compressed the mix you're limiting what he can do.
Some people prefer not to compress as they are recording, because what's on tape can't be undone, whereas if you compress while mixing you've more freedom to adjust things. Sometimes you don't have enough compressors to be able to do this though, and sometimes (say a singer that's whispering one minute and roaring the next) you just have to compress as you're recording just to get a manageable signal.
There's not much point in compressing distorted electric guitar (unless you're trying to add punch to the starts of the notes/chords) because the distortion effectively compresses the sound anyway.

What are pumping and breathing? Pumping and breathing are weird effects that can be caused by compressors. I've never had them pointed out directly by people who KNOW what they are, but I think breathing is when, if you have the make-up gain up very high and you suddenly come into a bit of silence, as the compressor releases you'll hear the background hiss getting louder and louder. Sounds kind of like someone taking a breath. Sounds really bad say on drums where you can hear the BANG of the drum then ssssSSSSS then BANG then ssssSSSSS. In this case you can get rid of it by making the release longer (so the compressor stays on between hits on the drum) or lowering the gain.
Pumping (again I'm not sure, but this is what I think) is when you're compressing a few things at once (say a whole mix) when everything gets suddenly quieter for a while, then gradually louder, suddenly quieter, gradually louder, etc. This can happen cos something, say a bass drum, exceeds the threshold and gets compressed but you've got the release set slow so the compressor takes a while to switch off (especially if you're using a high ratio, giving you a lot of gain reduction) so after the bass drum hit everything else suddenly gets quiet too, then gradually louder as it's released, then suddenly quiet again (another kick on the bass drum), then gradually louder etc. A faster release would help in this case.

What's a limiter? A limiter is basically a compressor with a ratio of infinity to one. It stops the level going over the threshold, end of story, no messing about.

What's hard-knee and soft-knee compression? In hard-knee compression the compressor kicks in as soon as the threshold is exceeded (after the attack time has elapsed). Soft-knee compression kicks in gradually around the threshold.

What's the difference between different compressors? Electronic compression can be carried out in a few completely different ways. Also, compressors can have very different electronic componenets inside (some of them are just software running on computers). Therefore they all sound different, even if they have the same knobs with the same shit written on them. If you want to know what's a good compressor for you to buy I can't help you - have a look on rec.audio.pro or talk to the guy/girl in your local music shop.

 

[Lord Damian]

i'm posting this before i read the Tale of Two Cities posted above:

what's the usual way to hook up compression? i just got myself a dual mono compression unit by dbX, haven't had a chance to read the manual yet...would i put the compressor in line between the mic and the board or would i add the 2 channels as inserts on the board?

i'm thinking this is a REALLY stupid question.

PS - i plan on using it for tracking only, not for mixdown (if i can help it)

 

[RED(tape)MENACE]

Insert.
You need to brind the mic preamp in your desk to bring the signal up to the correct level for the compressor to work with.
Remember not to go crazy - there's no way to undo any compression you apply while recording later on.

What dbx is it?

 

[Lord Damian]

Insert.
You need to brind the mic preamp in your desk to bring the signal up to the correct level for the compressor to work with.
Remember not to go crazy - there's no way to undo any compression you apply while recording later on.

What dbx is it?

it's the 166xl.
not planning on doing anything too crazy, just a bit on the snare, kick and lead vocal.