I have to admit that I was experimenting last night with Pacific’s Low Level Extension and it was not bad at all. It would not be my last words as I would need the whole system up and running to see what is going on – the region where the Low Level Extension it operates is VERY demanding. However my initial feelings were very positive. The Low Level Extension is not EQ but a dynamic-range-sensitive EQ – quite brilliant idea – through I do not know yet how it will sound at full bloom. The classical CD of References Recordings are a good illustration how it works….Anyhow, it is very exiting feature to play with… though I do admit that it is a forum of a compression….

From Pacific Microsonics Operating Manual: (disregard the text mentioning HDCD – I do not use HDCD encoding neither A/D nor in D/A)

Low Level Extension

Low Level Extension is an average signal level based low level compression / expansion system used on HDCD 16-bit amplitude encoded recordings which very gradually raises gain a preset amount when the average signal level drops below a preset threshold. During HDCD 16-bit decoded playback the compression curve is expanded back to linear gain by the HDCD decoder using a precisely mapped inverse of the compression curve controlled by a hidden code, producing a dynamic range and resolution floor beyond 16-bit. During undecoded playback low level information normally lost by standard 16-bit players is preserved, providing more accurate timbral and spatial reproduction.

There are two modes of Low Level Extension, “Normal” and “Special”. Normal mode begins to affect the input signal 45 dB below peak level, gradually raising the gain 4 dB as the level drops over an 18 dB range. Special mode begins to affect the input signal 39 dB below peak level, and gradually raises the gain 7.5 dB over a 26 dB range. Normal mode is optimized to provide the best combination of decoded dynamic range and resolution and nundecoded compatibility. Special mode is designed to provide the best possible decoded dynamic range and resolution at some potential expense of undecoded compatibility. Typically, Special mode is used only for HDCD 16-bit master tracking with the assumption that the recording will be decoded to a 24-bit or 20-bit word length for digital post production before being re-encoded to HDCD 16-bit using Normal mode to produce a release master.

Wide Dynamic Range Jazz or Classical

This type of material typically has infrequent, short duration peaks such as snare drum rim shots, cymbal crashes, bass drum hits, etc. These types of short duration peaks can be limited by as much as 5 dB or 6 dB using Peak Extension with little audible effect during undecoded playback, allowing the average recorded level to be raised which improves overall resolution and fidelity.

Low Level Extension, set to Normal mode, should almost always be used with wide dynamic range material as it greatly aids in preserving the low level ambient and timbral information that gives “life” and naturalness to recordings.

With certain types of source material, such as a very low level passage in a noisy analog tape, Low Level Extension may occasionally cause an audible shift or “breathing” of the noise floor during undecoded playback. Low Level Extension can be turned off “on the fly” prior to such passages when the signal level is above - 30 dBfs, and turned back on afterwards, again when the signal level is above - 30 dBfs, to preserve the best possible fidelity for the remainder of the recording. However, with source material that is very noisy, Low Level Extension should be left off, as the noise of the source will set the resolution floor.

A very good article on the subject that basically proves my attitude on the subject: it is not about technology but the idiocy of people who use the technology.

http://www.audiomisc.co.uk/HFN/ClippingOnCD/clipping.html

Romy the Cat wrote:

A very good article on the subject that basically proves my attitude on the subject: it is not about technology but the idiocy of people who use the technology. http://www.audiomisc.co.uk/HFN/ClippingOnCD/clipping.html The Cat

Turn Me Up!™ is a non-profit music industry organization campaigning to give artists back the choice to release more dynamic records. To be clear, it's not our goal to discourage loud records; they are, of course, a valid choice for many artists. We simply want to make the choice for a more dynamic record an option for artists.
Today, artists generally feel they have to master their records to be as loud as everybody else's. This certainly works for many artists. However, there are many other artists who feel their music would be better served by a more dynamic record, but who don't feel like that option is available to them.

This all comes down to the moment a consumer hears a record, and the fear that if the record is more dynamic, the consumer won't know to just turn up the volume. This is an understandable concern, and one Turn Me Up! is working to resolve.

http://www.turnmeup.org/

Romy the Cat wrote:

Turn Me Up!™ is a non-profit music industry organization campaigning to give artists back the choice to release more dynamic records. To be clear, it's not our goal to discourage loud records; they are, of course, a valid choice for many artists. We simply want to make the choice for a more dynamic record an option for artists. Today, artists generally feel they have to master their records to be as loud as everybody else's. This certainly works for many artists. However, there are many other artists who feel their music would be better served by a more dynamic record, but who don't feel like that option is available to them. This all comes down to the moment a consumer hears a record, and the fear that if the record is more dynamic, the consumer won't know to just turn up the volume. This is an understandable concern, and one Turn Me Up! is working to resolve. http://www.turnmeup.org/ The CaT

there are many other artists who feel their music would be better served by a more dynamic record

Paul S wrote:

The fact is, all orchestral processing/recording/broadcasting involves some sort of "compression", so it's really just a matter of how it's done.

Let do not forget that acoustic space also have own compression… not to mention that the performing intend itself has own “compression”.

Anyhow, I kind of view noondays the whole subject of compression slightly different then I use to do it before. I agree that various type of compressions rule playback but my interest is what type of compressions they are and HOW the compression applied. To a degree a properly made compressions might be in fact a beneficial tool. Someone before proposed it but I discarded it – now I feel that the idea of full-of-sense compressions had own merit.

The most interesting aspect to me in whole idea of compression is not the compression itself – we people who sit in the end sound chain have very little control over it. What interests me is hot to organize playback DIFFERENTLY in order to make the playback to sound the most properly with this or that type of compression. The compression itself is like an input parameter of some kind of function and the playback shall react to compression and to be able to deal with it…

Romy the Cat wrote:

Let do not forget that acoustic space also have own compression… not to mention that the performing intend itself has own “compression”.

Anyhow, I kind of view noondays the whole subject of compression slightly different then I use to do it before. I agree that various type of compressions rule playback but my interest is what type of compressions they are and HOW the compression applied. To a degree a properly made compressions might be in fact a beneficial tool. Someone before proposed it but I discarded it – now I feel that the idea of full-of-sense compressions had own merit.

The most interesting aspect to me in whole idea of compression is not the compression itself – we people who sit in the end sound chain have very little control over it. What interests me is hot to organize playback DIFFERENTLY in order to make the playback to sound the most properly with this or that type of compression. The compression itself is like an input parameter of some kind of function and the playback shall react to compression and to be able to deal with it…

Romy the Cat wrote:

Andy,   my mind does not operate by the categories you employ, I rather think about nature of Sound not about harmonic/non-harmonic distortions. The whole subject about the distortion is intricate, not to mention that it is not know if we in fact are able to recognize and adequately react to distortions. What I am saying that your explanation might explains something but nothing that I have practical or sensual experience with. The feeding system of sinewave tones and observation of introduced of harmonic or non-harmonic tone doe not proved to me anything about compression.  First, are you sure that the harmonic or non-harmonic problems come from compression itself but not from a wrong ways to inflict compression? You saddest to take my favorite digital compressor and set it up for some 'reasonable' amount of compression. Are you sure that in this case the sound will be ruined by compression but not by the DSP processing or by somthing else? Second, if you subtract the source from output during your “feeding system” experiment and hear juts distortions without the souses then what will you hear? I know what you will be hearing but the question is what would you be hearing that would allow you to make a cultural judgment about Sound? The answer is nothing. Therefore I do not tend to think about sound as compellation of original sound and distortion but I rather look at the whole sound, and I really know what to look for. Therefore I think that the proof in the pudding and what I observe is that a right amount and properly applied compression do not hurt sound, and in some cases very much improves it perception. Now, what would be the “right amount” and the “properly applied type” I have no idea. The caT

As things stand today, I believe that the biggest gain in quality is not to be had via the pursuit of higher resolution formats.

A friend of mine who works for a large media distribution business (like Amazon) recently gave me a bunch of sample CDs that were left over from previous evaluations in their listening room. Record labels regularly send these samples out to large retail operations hoping to secure an order. Many of the CDs are bare, with no cover art, and have only a simple hand written title for purposes of ID. Most have a word saying something to the effect that the material is "not for resale". Listening to these recordings revealed in all cases a total absence of dynamic compression; they actually sound really good.

This is somewhat surprising, as I would have thought all mastering to have been done before issuing even the pre-sale samples, but apparently not, or apparently there are two versions (one compressed and one not). In any case, I interpret this finding as an admission on the part of the labels that the effects of dynamic compression are in fact detrimental, and that people running the labels are completely aware of the damage it does.

Though the material on newer (purchased) CDs seems to have less dynamic compression than was the case with CDs from about 3 years ago, it is still present and widely used, and I fully expect that the commercially available versions of these samples will receive the compression treatment.

This I just do not understand... The original motivation (mastering a recording to sound louder than offerings from competing labels when broadcast over the radio) is no longer valid; as a result of this practice (dynamic compression to increase perceived loudness), broadcast signals are now processed before diffusion such that perceived loudness is held at a constant level. Unless I am missing something, there is no longer any reason to continue the practice of dynamic compression; I just don't get it !

The only possible motivation I can imagine is in the context of an individual listening to music files in a noisy environment (an MP3 player used in the subway for example); such a user might "benefit" from dynamically compressed files where the quiet passages are boosted. So is that it? Is this what's dragging down the quality for all users? There has got to be a better way!

jd*