drtechno
100+ Head-Fier
- Joined
- Nov 14, 2016
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"The Pro Tools mix engine has traditionally employed 48-bit fixed point arithmetic, but floating point is also used in some cases, such as with Pro Tools HD Native. The new HDX hardware uses 64-bit floating point summing." - Wiki
"Mixing level scaling stores 48-bit results using a 56-bit accumulator for maximum precision." - 1999. Pro Tools 5.0.1 Reference Guide (page 283 explaining the TDM mix architecture, introduced in 1994).
"Steinberg has labeled Nuendo its "Media Production System" and with good reason. Open the program, click "New Project," and there's a list of various application templates ranging from Pro Logic Video Mixdown and 24/96 DVD 5.1 Authoring to 32-bit Stereo Master and Audio/MIDI Music Production." - Mix magazine review of initial Nuendo release.
OK, I've provided some back up for my statements, now it's your turn! Provide corroborating info that Nuendo ever had a 24bit mix environment, that Pro Tools or Nuendo ever had a 40bit mix environment. Of course, you won't be able to do that! Even a relative newbie recording, mix or mastering engineer knows that Nuendo is a host based platform (and can therefore can't be anything other 32 or 64 bit mix environment), let alone someone who's been in the industry for 25 years! It's also inconceivable you wouldn't know the basic architecture of the industry standard DAW software (Pro Tools). Likewise, one might have to explain to a 1st year music technology student that at least 3 of the 24bits cannot be anything other than thermal (Johnson) noise and therefore that a 40bit file format with an additional 16bits of thermal noise is ridiculous but one would be shocked to have to explain that to practising professional, let alone a 25 year veteran!
For this (and several other reasons), your pre-emptive excuse: "I am recalling from memory" is hogwash. There's only one way that someone professing to be a highly experienced professional audio engineer could "recall from memory" something which so obviously flies in the face of basic digital audio theory, and that's if they have no understanding of basic digital audio theory and must therefore be lying about being a highly experienced audio engineer! What I find baffling is that even after your lie was exposed, you continue to defend your "facts" as not just made up and challenge those of us who have in fact been pro audio engineers for 25 years (or more). Regardless of why you decided to post made up "facts" in the science forum and regardless of whether you're willing to publicly admit it, you (and many/most of us) know that you made them up and you must surely realise that continuing to defend those "facts" will achieve nothing besides digging a deeper hole for yourself!
My apologies to others if my challenging of this member seems overly harsh but there's already way too much made up BS from marketers/retailers in the consumer audio world, without having to waste time dealing with someone just making up BS for self-aggrandisement and/or the fun of misleading others!
G
basic audio theory don't cover programs. and the theory of 16 extra bits of thermal noise is flawed. but the 40 bit is unpublished info I got from a protools daw programmer that programmed may daws besides protools.
that part doesn't matter. but if you really want to know about value spacifics , A 64-bit engine is technically not better than a 32-bit engine for summing.
A 32-bit engine does all calculations on the fpu, thereby using registers that can be as large as 80 bit. (The accumulator even extends this)
A 64-bit engine has no other choice than using SSE instructions, of which the registers are limited to 64 bit strings. Some people will argue that SSE strings are 128 bit, but that's incorrect. The 128 bit string is split up in two 64 bit strings.
So, if well written, a 32-bit audio engine can be more precise than a 64 bit engine, since it can hold larger strings of numbers.
That is when the numbers are kept as long as possibly can in the registers and are brought back to 32-bit as less as possible.
On the other hand, 64-bit is more precise than 32-bit thereby avoiding any rounding errors. But these rounding errors are neglectable when it comes to adding and subtracting numbers, which is what a summing engine basically does.
Rounding and additive (cumulative) errors are important for any process where DSP is concerned, but all DAW and plugin manufacturers are already using double precision for most -if not all- of their critical calculations.
In practice 32 bits vs. 64 bit will make no difference at all, unless you are really abusing the audio engine and are burning every gain stage by dozens of dB's and/or in scientific tests set up to expose the problem. In every day use (read: proper use) there shouldn't be any difference.
In other words, if you can hear (and measure) the difference between a 32-but engine and a 64-bit engine, then something is/was wrong (badly designed) with the 32-bit engine to start with.
In a properly build DAW, the numbers are not stored in 32-bit strings, but kept in the FPU registers as long as possibly can before they are dumped (and rounded) to a 32-bit string. Thereby the intermediate roundings (80 bits =>32 bits) are much less frequent, than when using SSE strings which need to be dumped as soon as the 64bit strings are "full".
Of course, depending on the internal structure of each an every DAW -and the way things are tested- there are arguments in favor of both techniques. All I said is that in normal, proper, non-abusive use, the (rounding) error in a 32-bit mixer will remain in the LSB's, exactly as in a 64bit mixer.
some other fun facts:
8-bit = 256 Dec.
100000000 Bin.
Dynamic Range = 48.16dB
16-bit = 65536 Dec.
10000000000000000 Bin.
Dynamic Range = 96.32dB
20-Bit = 1048576 Dec.
100000000000000000000 Bin.
Dynamic Range = 120.4dB
24-Bit = 16777216 Dec.
1000000000000000000000000 Bin.
Dynamic Range = 144.48dB
32-Bit = 4294967296 Dec.
100000000000000000000000000000000 Bin.
Dynamic Range = 192.64dB
64-Bit = 18446744073709551616 Dec.
10000000000000000000000000000000000000000000000000000000000000000 Bin.
Dynamic Range = 385.28dB
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