Music Volume Compression: the Dirty Little Secret...

[Bernie]

This topic has come up before, but here's something I received today...

Music Volume Compression: the Dirty Little Secret Your Record Company Doesn't Want You to Know.

Buying a commercial CD these days is very expensive and very risky.** Many consumers have noticed that their new CD's lack the "energy" and "excitement" of the original vinyl recording. Apparently, CD manufactures think that "louder is better" and to make their CDs sound louder, they have greatly compressed the sound level.* This means that they have raised the volume of soft music passages while lowering the volume of loud passages. The result is more average volume but also a very boring, lifeless recording.* This should never be the case, as the CD medium is capable of a dynamic range in excess of 90dB; this is about 30 times better than that of the best vinyl records.

CD recording engineers may find this procedure to be expedient, as it no doubt makes recording easier.* This same type of audio processing is used in AM and, to a lesser extent, FM radio stations to increase their range and to stay with-in FCC regulations.* However, when used on a commercial CD recording, volume compression results in a serious reduction in sound quality. In truth, volume compression is distortion and this distortion cannot be removed by the customer in any simple way.* For some reason, rock oldies CDs seem to suffer the most. Classical music recording almost never use volume compression and therefore almost universally have excellent sound quality.

I think this situation is inexcusable and no doubt contributes to more and more people purchasing their own CD recorders or acquiring (read: stealing) music via the Web.

I can only hope that somehow, more CD manufacturers will "clue-in" and start producing decent sounding CDs again..* What's at stake here is the music itself.* When all the albums, reel-to-reel tapes, and 8 tracks are gone all we will have left is lifeless, boring, compressed garbage.

Sincerely,
Charles Kitchin (electronics engineer)

[QUINNY]

Oh well Bernie, he has his opinion and I don't particularly agree with it.
You can plot the use of ultra compression to two important factors. Firstly as mentioned, AM and FM radio and their need to be listenable in a car. Secondly, cassettes and latterly CDs and their need to be heard in a car. With cassettes and AM radio in particular, the use of ultra compression made the music sound better 'cos the noise floor was less evident on playback. These are the factors that have driven (no pun intended) the use of high compression levels.
I personally feel that judicious use of multiband compression can make almost any music sound more exciting, because it acts like a loudness button. With valve simulation, aural excitement etc most types of music will sound better, if left in a good engineer's hands.

The really damning thing is: In the 1970's especially, recording engineers used all sorts of heavy compression techniques when recording. They'd commonly use pre-emphasis, whereby they'd deliberately record tracks with added top end, which they cut off in mixdown as this supposedly gave them a better signal to noise ratio i.e. masters with less tape hiss. Now, on an analogue deck, this pre-emphasis would in effect compress the top end frequency, sometimes substantially. They were in effect almost using a dolby type of noise reduction, but with maybe less well defined parameters.
The other thing they really started to do in the '70s was to record 'hot'. i.e. they'd record tracks so that the VU meters were hitting the red all the time. VU meters are notoriously slow compared to today's digital peak meters, so the actual levels going to tape could have been some 20 dB higher. This would have distorted things horribly in real terms, even though it may not have been so apparent. All of this had the effect of squashing the top end response and lowering overall noise levels, again leading to masters with less hiss and a limited dynamic range, even without brick wall limiting (which would have been applied at the disc cutting stage) or heavy compression (which would have been used). To some extent, they didn't need to do this, as everything ended up on vinyl with its limited dynamic range, but they did.
This could be why some '70's stuff maybe ends up sounding less than wonderful, but I have to say that I haven't come across any transfer from master tape that sounds worse than the vinyl in overall terms. Disc transfers are another matter altogether.

Compare that to digital recording where hiss is negligible, where what goes in, to all intents and purposes, comes out, where microphones are so much better (in top end response especially), outboard equipment is so much better in transient response, distortion is virtually zero and everything only has to be ultra compressed at the final mastering stage, just before it's released. O.K. there may be engineers with cloth eras, but don't blame the use of heavy (incredibly transparent) compression per se.

[Bernie]

Oh well Bernie, he has his opinion and I don't particularly agree with it.

Why does this not surprise me?

You can plot the use of ultra compression to two important factors. Firstly as mentioned, AM and FM radio and their need to be listenable in a car. Secondly, cassettes and latterly CDs and their need to be heard in a car. With cassettes and AM radio in particular, the use of ultra compression made the music sound better 'cos the noise floor was less evident on playback. These are the factors that have driven (no pun intended) the use of high compression levels.

I realize the half-ass reason the studio engineers decided to destroy the sound with compression. A better solution would be to build the user defeat-able compression as a switch / preset on the car's head unit or Walkman device so as to leave the CD and the music in its original and untarnished state. At least the listener has a choice.

I've painstakingly assembled a nice audio system so I can hear the music in all its glory. Give me un-compressed and non-eq'ed sound anyday.

[QUINNY]

Bernie: I detect a certain weariness in the first part of your reply. :lol:

Don't you think that Hi-Fi itself is one of the biggest lies of the 20th century? Anything you hear on CD, record, DAT or whatever is only an approximation of the actual sound. It's a Japanese or American or English electrical engineer's idea of what constitutes a good sound. Even unEQ'd, uncompressed Hi-Fi is nowhere near the truth in pure aural terms.
Just put up any microphone and any speaker combination and record the human voice. Do we hear rumble, popping, sibilance (or any other artifacts that you invariably get), with our ears? Do we hear any of the roominess? No. I do a lot of voice recording in sometimes hostile recording venues, and you'd be amazed at how many times what sounds like a quiet room to record in, has so much crap noises in the background. In the UK it is now almost impossible to record a Choir for instance, without some sort of noise screwing things up at some point or another.
As soon as you put a microphone up to record anything, you ain't gonna get anything like the true sound. Yes, I do EQ and I do compress choral recordings, otherwise they just wouldn't sound completely right. Even with extremely quiet recording gear, some sounds could get lost in the general background mush. Close mic, in a dead studio, use 16, 24, 32, 40 tracks and forget any notions of Hi-Fi or realism, but a 2 track straight to stereo recording just wouldn't be acceptable either. You wouldn't have had the thumping bass drums, cracking snares and the like on disco records, recording like that; but that is the hi-fi purists answer.

I'm sorry, but as far as I'm concerned, Hi Fi freaks are just that. They hear things in the sound that not even the producer/engineer/artists were aware of in the recording and then criticize the sound. They have no awareness of what goes into a final mixed product and the miriad decisions that might have to be made at each step of recording. Does it really matter that much? No. It's what's in the music that matters, not the bloody sound!!!

Yes, a compressor in the car audio or home stereo might have been a better solution, but even that has its flaws. Personnaly I reel in horror at the thought of Joe public being able to remix (having 16, 24, 32 tracks) songs to their own preferences (which if not already with us, is just around the corner). It's like going to a bakers shop and asking for a meat pie and saying you'd like the meat going into it to be on hold until you get home and decide which filling you'd like.
IMO: Having totally uncompressed, un EQ'd CDs would be a complete nonsense, unless you really want CDs to sound like crappy live performances at which you have possibly the worst seat in the house.

[BrunoRepublic]

I for one am totally sick of ultra-maximized/compressed CDs. I know radio needs compressed music, but they already have the necessary equipment on their end for that. Heavy compression robs the music of dynamics and life, and is fatiguing to listen to. Coldplay's "Clocks" is a good example; the impact of the drums when they first kick in is totally lost because the music is already hitting 0db. CDs are maximized not to make the music more exciting or dynamic (which is where analog compression during mixdown comes in) but simply to make them LOUDER than other CDs in your collection because everyone thinks LOUDER IS BETTER. Several recent CDs have been mastered with nothing but loudness in mind, and the result is just a blast of sound. At the current rate of progress, music will degenerate to booming white noise in a few years.

Best disco example of a track ruined by hard-limiting: El Coco's cover of "Caravan" on the Disco 54: AVI collection. On the original LP (which was probably considerably compressed to begin with), the drums in the chorus simply blast out of the track, being a good 3db higher than anything else in it. But on the CD, everything is maximized to 0, which means that they are cut by 3... so they have no impact, sounding tame and timid. It defeats the whole point of the track. And the track seems to be drowning in reverb, but it's just because the low-level signals have been brought up and out of proportion.

I hope someday soon enough people will realize that hard-limiting music is destructive and unmusical. Perhaps the practice will be regarded with total disdain as fake stereo processing of mono LPs is now. If you want it loud, turn up the volume. REAL MUSIC IS DYNAMIC!

[QUINNY]

Originally Posted by Graham Start

CDs are maximized not to make the music more exciting or dynamic (which is where analog compression during mixdown comes in) but simply to make them LOUDER than other CDs in your collection because everyone thinks LOUDER IS BETTER. Several recent CDs have been mastered with nothing but loudness in mind, and the result is just a blast of sound. At the current rate of progress, music will degenerate to booming white noise in a few years.

REAL MUSIC IS DYNAMIC!

Graham: If you accept that compression of individual tracks is OK then sure you can't gripe too much at overall compression of final mixes. Another reason these things are compressed at final stage mastering is to make sure levels do hit 0dB and the CD will at least take full advantage of the dynamic range that's available. It doesn't happen so often now, but you'd be surprised at how many different levels master tapes are recorded at. Subjectively, a master that hits 0dB but averages at -30dB is gonna sound incredibly quiet compared with one that averages only 6dB higher. So much so that some people may not be able to get as much out of it as they'd like volume wise (another reason why things are the way they are).
I agree, music is dynamic, but disco music in particular was never about such niceties. On the El Coco track, the drums would have been way up in the mix to be 3dB louder than anything else. This might have been a 'mistake' on the original mixdown and hey, weren't vinyl records themselves limited to death, because of cutting limitations. Any record you have is hardly a true reflection of the master tape is it, so how can anyone be sure that a transfer to CD isn't more like what the original engineers intended? I don't think it's so cut and dried. The reverb question comes under the same umbrella. How can you, in all relality say that a medium with at best 40dB of dynamic range has a truer sound than one with 105dB. Most disco records I own don't back off of 0dB much, once they get started. Loudness in a final product has been the engineer's holy grail for much longer than the past 5 years or so.

[BrunoRepublic]

Originally Posted by QUINNY

Graham: If you accept that compression of individual tracks is OK then sure you can't gripe too much at overall compression of final mixes.

Within reason, yes. But the amount of limiting we're seeing on current releases is absurd.

On the El Coco track, the drums would have been way up in the mix to be 3dB louder than anything else. This might have been a 'mistake' on the original mixdown

Likely not. If you've heard the track in question, there's no doubt about it. The drum hits in the chorus are slammed down with full force, and are meant to leap out of the speakers. They are a sonic exclamation mark. But on the CD comp, they're merely a period.

and hey, weren't vinyl records themselves limited to death, because of cutting limitations.

Yes, but the irony is that while CDs have a much larger dynamic range than vinyl, most current CDs have considerably less dynamics than their original vinyl counterparts.

If audio purity is the goal, then maximizing a disc to take advantage of all 16 bits at all times seems rather self-defeating. Would consider someone holding the volume knob on your stereo and constantly twitching it with every beat to be making the most of the format?

Any record you have is hardly a true reflection of the master tape is it, so how can anyone be sure that a transfer to CD isn't more like what the original engineers intended?

True, but this to me is a case of bad and worse.

How can you, in all relality say that a medium with at best 40dB of dynamic range has a truer sound than one with 105dB.

That's my point exactly. LPs shouldn't have more dynamic range -- yet many of them do. It shouldn't be this way.

Most disco records I own don't back off of 0dB much, once they get started.

True of some (Tom Moulton's early mixes for example; Gloria Gaynor's first two LPs are compressed to death), but not of others. Pull out original American copies of any Rinder & Lewis LP and you'll see incredible dynamics (note: the UK copies pressed by Pye were very badly compressed, as I discovered when I got a UK issue of "Seven Deadly Sins"). "Le Spank" is a good example.

Loudness in a final product has been the engineer's holy grail for much longer than the past 5 years or so.

Yes, but not to this extreme. With vinyl, it is an accepted fact that some records will be louder than others due to bass, channel seperation, duration, etc. But all CDs have the 0db limit, and everyone seems to be pushing everything up there.

[QUINNY]

Quick question to anyone reading this: Do you think today's audio mastering engineers use their ears so little, that they don't realise what they're doing? I, personally, would not be able to accept this as mastering is something done by real audio heads and /or by people with years of experience, exactly for the reason that they could screw things up at the last minute.
I can only assume that the examples of really poor mastering have been done 'on the cheap', or on drugs (something that was just as prevalent back in the '70s?), or possibly from masters that were utter shite in the first place. You can't make a silk purse out of a sow's ear, eh?. Perhaps those AVI pressings were actually O.K after all.

[BrunoRepublic]

Originally Posted by QUINNY

Quick question to anyone reading this: Do you think today's audio mastering engineers use their ears so little, that they don't realise what they're doing? I, personally, would not be able to accept this as mastering is something done by real audio heads and /or by people with years of experience, exactly for the reason that they could screw things up at the last minute.

According to some of them, it's the record companies who insist that the discs be LOUD LOUD LOUD as possible. The engineers have to follow their instructions if they want to stay employed.

Perhaps those AVI pressings were actually O.K after all.

The mastering on most of them is excellent. It was the quality of the vinyl that was crap.

[QUINNY]

So you're saying the lunatics have taken over the asylum. Hmmm, I guess this could be the reason, but most record company fat cat execs wouldn't be smart enough to think of doing that off their own bat. Some engineers must have convinced them of it in the first place. Wadya think?

[Sami M]

This is an interesting thread!

I'm not an expert on sound compression. I too have tried to put up a decent sound system and so differences between recordings and sound sources are obvious. I do not have any cd reissue or whatever that sounded better than the original on vinyl. The vinyl has always better, cleaner sound and wider stereo/space effect. The cd comes full on on all frequencies and just losts the structure.

Well the radio sounds just damn awfull and I acctually sold my tuner, but that's becouse the radio stations are just crab here playing what I don't care to hear.

But here's the difference that I have noticed. I have some eighties reissues on cd aswell and they do not sound as bad as the 70's stuff. So more than compression I have gathered that the overall poor quality of disco cd's is due to the use of powerfull noisereduction. I have had a separate pro dbx equipment with my open- reel recorder. It was very efficient with the tape hiss but I just did not like the sound. Like I don't like the sound of oldies cd's. It's just too overmpumped and repressed at the same time.

And oh, not all seventies vinyl sound good. Merely only the original releases. Isn't this due to something with copies of the mastertapes and remastering process? I mean, they didn't send the original master tapes to Brazilia or Holland to press vinyls to the local markets there.

I know that Hi-Fi is an illusion of a kind. But you can't deny that if the sound just floods over you and you can separate any section in particular there is something wrong with the recording. As mentioned the classical music on cd's is usually superior. And that is to the same style that old disco vinyls sound.

From modern cd's e.g. Madonna's Ray of light by William Orbit is a good recording and contains huge amounts of details and is a very rich sonic experince. As is some Juno Reactor's stuff, just to name few. Actually both contain a stunning bassline effect that like comes ahead of you and lurks under you, tickles your butt/feet and then is gone.

So it's not alwyas the compression and use of machines that is the reason.

[paul]

Fascinating discussion. I'm sorry it took so long for me to jump on board. The compression issue should come as a surprise because we have a mp3 generation that like the same over and over with little variation musically and dynamically. With this as a reality, there really is no need for DVD-Audio or SACD except to thwart piracy. Those two formats were designed with that in mind.
Quinny, have listened to any audiophile vinyl, Direct to Disc, etc.?

[Nano]

After reading this for awhile I think I get what you guys are talking about. This connects with an old post of mine regarding the low volume of British CD editions of Genesis/Peter Hammill old 70's albums. See, I am one of those guys who turns the volume up and down listening to those CDs because every time the song goes acoustic it seems to lose itself in the air! So I guess I'm a bit deaf on your points of view :) Another thing: I don't hear any great difference between a WAV song archive and a 128 kbps MP3 version, so obviously all those years of dancin' made something to my ears! :roll:
I think that drum effect Graham and Q. are discussing is similar to that I hear when doing a live recording with a small home tape recorder (i.e. journalistic interviews). Anytime a loud sound occurs, it seems to cover anything else that comes later for a few seconds, the whole volume turns down. The same if recording a band with the buil-in mic of that tape recorder: when the song begins acoustic, it seems to grow louder and louder till the first drum roll... then all sounds quieter and the ambience noise is gone.
Am I getting it, fellas? :roll:

[Bernie]

Nano, the problems with your recorder is that it most likely has AGC: automatic gain control that constantly "tries" to control the recording volume by riding the gain. If there is a switch to defeat it you may want to try that for a more natural sound. Some machines call it ALC for automatic level control. If you have one of the Marantz PD series or Sony TCD6's you should be able to.

[Nano]

I knew it, I knew it... deaf without pity! :cry: