Alan Parsons on compression - from the man himself...

[SJ_Digriz]

I think that I must be mistaking something:
I thought that the word we are all throwing around, "dynamics", (which by the way doesn't actually mean anything as a description on it's own - sound has several kinds of dynamic) meant that there was movement within the individual sounds, and/or bewtween parts that happen concurently; I am confused, because it seems to be getting described as the difference between the 'loud part' and the 'quiet part'. That doesn't seem right somehow. Like the example that was given from Pink Floyd; the quiet muttering, then the music comes in louder... that's not really an example of what I understood to be "dynamic" when referring to audio production, and even less so when referring to compression.
Am I wrong?

It is almost as simple as loud vs soft. But, what happens now is lets say you have an acoustic guitar part that goes with a song. The absolute level of that guitar will not waver + - .01 db through the entire song. Any given keyboard sound will not waiver throughout. The song itself will have the quiet parts jumped up by a compressor so even though it might be someone whispering, the actual level will be still in the -6 to -4 range.

So, it applies to almost every aspect of music now. From individual instruments/voices all the way to the final master. The engineers make every attempt to remove as many volume changes as they can from a song. They are only "allowed" at intros, bridges and endings. This gives them the freedom to pump the Average level up because they have to deal with fewer peek transients. But, it removes space and life from the songs and limits the ability of some very talented musicians to express themselves on their instruments.

{edit} Obviously I hope you guys know this is a generalization.

[McLilith]

It is almost as simple as loud vs soft.

Loud vs. Soft

I like that. I might use that as a title, or a band name.



McLilith

[Z3R0T0N1N]

It is almost as simple as loud vs soft. But, what happens now is lets say you have an acoustic guitar part that goes with a song. The absolute level of that guitar will not waver + - .01 db through the entire song. Any given keyboard sound will not waiver throughout. The song itself will have the quiet parts jumped up by a compressor so even though it might be someone whispering, the actual level will be still in the -6 to -4 range.

So, it applies to almost every aspect of music now. From individual instruments/voices all the way to the final master. The engineers make every attempt to remove as many volume changes as they can from a song. They are only "allowed" at intros, bridges and endings. This gives them the freedom to pump the Average level up because they have to deal with fewer peek transients. But, it removes space and life from the songs and limits the ability of some very talented musicians to express themselves on their instruments.

ahhh. clarity. so it does include what I thought it didn't.

@mclilith:
you should definitely use the long version

[xander]

Most live recordings of symphony orchestras and piano recitals use no compression at all.

[Z3R0T0N1N]

@Mclilith:
re-read some of your reply, and you kind of cleared up something for me.

as for what I always thought of as dynamics (and thus what I figured was the Main Problem of over compression was the diferent velocities of keys, hard strums vs soft/picking/etc., and just the overal movement of sound amplitude in and during an arrangement. I thought less of the type of example given; but you are right about what would happen. I just never really considered that anyone would do that, if a part was meant to be soft and quiet, such as an incidental sample added in the background for mood, or whatever. I can't think of an example of when even the worst engineer would do that, but you never know..
cheerz.

[McLilith]

I thought less of the type of example given; but you are right about what would happen. I just never really considered that anyone would do that, if a part was meant to be soft and quiet, such as an incidental sample added in the background for mood, or whatever. I can't think of an example of when even the worst engineer would do that, but you never know..
cheerz.

I suspect that similar things happen more often than many of us would expect--especially if the soft part isn't at the start or finish of a song, but somewhere in the middle. I think some people compress the crap out of mixes, to make sure that the weak parts don't get lost when the song is played in a noisy environment, such as an automobile, a boombox in a noisy room, or the audio system in a noisy night club.

It also helps those people with sound systems which are lacking in power. Source material with wide dynamic range can require more reserve amplifier power, to sound like it's played at an appropriate volume. Sure, you'll always hear the loud bits, but in order to hear both the loud bits and the softest bits with equal clarity, you'll need an amplifier with enough headroom. A 5W boombox doesn't have much useable range. The softest parts can easily be buried in room noise. Compressing the crap out of the mix will help make the most of a small amp's power capacity. It might not sound natural, but at least you'll hear it.

Since there are lots more people listening in their cars, and on various types of low-powered audio systems, than people with large high-quality power amps and large high-quality speakers, I think the record companies do sometimes tailor the compression to suit this larger audience. (I'm primarily thinking of pop music.) Those people with the nicer equipment are effectively penalized, which is a crying shame, because they are often the ones who wanted to hear the music the most! (Why else spend all the money on expensive gear, if you didn't really want to hear the music better?)

How often this sort of thing happens, I don't really know, but I do suspect that it happens regularly.


take care,
McLilith

[bMachine]

Most live recordings of symphony orchestras and piano recitals use no compression at all.

true, uses very little compression and limiting, but because classical music is based on very large dynamic differences, which is not so good for music most of us made. Namely, radio/tv is the problem, when it`s intended to maintain similar loudness (and therefore dynamics) through whole time of reproducion.

[McLilith]

Namely, radio/tv is the problem, when it`s intended to maintain similar loudness (and therefore dynamics) through whole time of reproducion.

Radio and TV stations actually keep compressor/limiters wired into their systems. They can't allow their transmitter to be overdriven (over-modulated), so they practically have to use compressor/limiters. The compressor also makes their signal seem "stronger" to the average listener. You see, the "volume war" didn't start with albums...

I think the excuse of heavily compressing a recording for airplay purposes is overrated, considering that the radio or TV station is going to compress your recording anyway. Also, radio and TV receivers have AGC sections which can also wreak havoc on the dynamics of received music.

Just tune to a moderately strong FM station (one with a little bit of background noise), and listen to the noise floor rise and fall, depending on how loud the program material is. The softer the program material, the louder the background noise will become. Now, that's some heavy compression. I'd say a recording doesn't need a lot of compression built into it, since airplay adds so much compression of its own.

So yes, radio and TV compress things heavily. I still don't see much need for compressing an album heavily, especially with the excuse of making it more "radio friendly". The people and equipment at the radio station will make sure your signal is "radio friendly" without you having to do anything to your album.


take care,
McLilith

[Sascha Franck]

So yes, radio and TV compress things heavily. I still don't see much need for compressing an album heavily, especially with the excuse of making it more "radio friendly". The people and equipment at the radio station will make sure your signal is "radio friendly" without you having to do anything to your album.

Exactly the point!
But then, people are being trapped all the time nonetheless.
"Let me just load in this track for comparison."
"Uh, sounds way louder than my own - let me check out this MB compressor!"

Of course, in case you're doing dancefloor music, your tracks need to be comparable, but I can't think of much more reasons to compress the shit out of whatever material.
IMO compression is good for surgical operations, such as to avoid clips that won't add anything to the perceived sound anyways, let's say a very high frequency peak in a snare that otherwise is just sounding fine.
It's also good to suit some "modern needs", such as in compressing vocals to make them sound really close.
It's also fine for the occasional master limiting, should you ever forget about some individual signals.
And finally it's also fine to somewhat compress a complete track - but then, IMO this has to be done carefully, VERY carefully. You just don't want to be your acoustic guitar bridge passage to be as loud as the fullblown chorus. At least I don't want.
Unfortunately this is happening a lot though...