Print

Please login or register.
1 Hour 1 Day 1 Week 1 Month Forever
Login with username, password and session length

[Tomás Mulcahy]

What have I started? Funny though. Thanks Bob, as always, for your clarity.

[brett]

Bob Olhsson wrote on Wed, 24 August 2005 18:11

Digidesign just doesn't go out of their way to point out the advantages of le over TDM.

So you are saying the sound quality of processing in LE exceeds that of TDM. There are so many pro's that I have seen writing posts here on these threads that say the TDM versions of Plugs sound better than the Native version including the LE versions. I use the L2 for example. Numerous Me's wrote that the TDM version was cleaner than the Native Version. I can't back this up, just letting you know what I read.

But, I don't really see how truncating a 32bit float will sound better than a 48bit fixed split evenly by two. There is no quantizing needed to return to the buss. I guess the quantizing and truncation goes on as it reaches the limit of the fixed 48 bits and that could be it. Please clarify your remarks.

[Chris Cavell]

Gerald Leitch wrote on Wed, 24 August 2005 11:51

With the LE sytems, be it 001, 002 or M-box they are all set to record at 16 to 24 bits, sure all types of plugs operate at different depths but the LE depth is 24. Most waves stuff dithers internally down to 24 bits on LE as do others.If you send a link to show me an page stating LE does operate at 32 bit float then cool it's just I've yet to find one.

Not true.  You can look in just about any waves plugin manual and read with little variation from plugin to plugin:

from the Waves Renaissance compressor manual

New to the processor is dithering for the final output. TDM output is dithered to 24-bit (fixed point); native output is dithered to 32-bit (floating point). In both cases the signal is "handed back" to the application being used. In TDM, the internal resolution is 56-bit fixed point; in native, it is 64-bit floating point.

The entire LE signal path is 32 bit floating point.  LE is a "native" system.  Every insert point throughout the system has 32 bit floating point I/O, and the stream doesn't get converted back to 24 bit fixed until after the last insert point on the master fader.

[Ged Leitch]

Chris Cavell wrote on Wed, 24 August 2005 19:54

Gerald Leitch wrote on Wed, 24 August 2005 11:51 With the LE sytems, be it 001, 002 or M-box they are all set to record at 16 to 24 bits, sure all types of plugs operate at different depths but the LE depth is 24. Most waves stuff dithers internally down to 24 bits on LE as do others.If you send a link to show me an page stating LE does operate at 32 bit float then cool it's just I've yet to find one. Not true.  You can look in just about any waves plugin manual and read with little variation from plugin to plugin: from the Waves Renaissance compressor manual New to the processor is dithering for the final output. TDM output is dithered to 24-bit (fixed point); native output is dithered to 32-bit (floating point). In both cases the signal is "handed back" to the application being used. In TDM, the internal resolution is 56-bit fixed point; in native, it is 64-bit floating point. The entire LE signal path is 32 bit floating point.  LE is a "native" system.  Every insert point throughout the system has 32 bit floating point I/O, and the stream doesn't get converted back to 24 bit fixed until after the last insert point on the master fader.

I really don't think we should continue hijacking dongles thread like this but if you insist...
Waves L2 IS dithered to 24 bits in LE as is linear phase EQ and linear phase multiband if the dither control is on and 32 bit float Only if the DAW is 32bit float, this I have just read again from the pdf's.
I'm still waiting to see a link describing Pro tools LE's bitdepth as 32 bit float?
By no means am I questioning your authority on this matter, however I always like to see some form of official documentation on these matters I will admit if I am in the wrong and need corrected.
cheers.

[Chris Cavell]

Gerald Leitch wrote on Wed, 24 August 2005 14:24

I'm still waiting to see a link describing Pro tools LE's bitdepth as 32 bit float? By no means am I questioning your authority on this matter, however I always like to see some form of official documentation on these matters I will admit if I am in the wrong and need corrected. cheers.

Totally understood...really not trying to be argumentative or a hi-jacker on this end.  Just trying to clear up a point of contention.

If you have the 6.4 Ref guide, check page 430, right hand column, 2nd paragraph, first sentence.

If you have th 6.9 ref guide:
p. 473, left column, 2nd par., 1st sentence
p. 534, the two bulleted items at bottom left of page
p. 546, the section titled "24-bit Input and Output"

I think maybe these will sort the matter out for us.

[Ged Leitch]

Chris Cavell wrote on Wed, 24 August 2005 20:39

Gerald Leitch wrote on Wed, 24 August 2005 14:24 I'm still waiting to see a link describing Pro tools LE's bitdepth as 32 bit float? By no means am I questioning your authority on this matter, however I always like to see some form of official documentation on these matters I will admit if I am in the wrong and need corrected. cheers. Totally understood...really not trying to be argumentative or a hi-jacker on this end.  Just trying to clear up a point of contention. If you have the 6.4 Ref guide, check page 430, right hand column, 2nd paragraph, first sentence. If you have th 6.9 ref guide: p. 473, left column, 2nd par., 1st sentence p. 534, the two bulleted items at bottom left of page p. 546, the section titled "24-bit Input and Output" I think maybe these will sort the matter out for us.

Don't have the 6.4 ref guide just the individual pdf's for each plugin.I know what your saying though that the plugins are dithered to 24bit in a 24bit daw and 32 bit float in a 32 bit float daw with the dither off.
But It's mainly about LE being 32 bit float that puzzles as I have not seen any docu regarding this, all I've seen is 24bit.

[MT Groove]

Chris Cavell wrote on Wed, 24 August 2005 20:39

If you have the 6.4 Ref guide, check page 430, right hand column, 2nd paragraph, first sentence. If you have th 6.9 ref guide: p. 473, left column, 2nd par., 1st sentence p. 534, the two bulleted items at bottom left of page p. 546, the section titled "24-bit Input and Output" I think maybe these will sort the matter out for us.

And on 6.7, there is a reference of it on page 455 2nd paragraph.

For those who don't have access to these, it goes as follows.  

"Pro Tools TDM systems process all audio internally at 24-bit, and Pro Tools LE process internally at 32-bit, floating."  

[Chris Cavell]

Gerald, here are links to the Pro Tools Reference guides for your viewing pleasure...check the areas I have pointed out to you in my previous post...this is the documentation you've been seeking:

http://akwww.digidesign.com/support/docs/69/Pro%20Tools%20Re ference%20Guide.pdf
http://akwww.digidesign.com/support/docs/PT_6.4_Reference_Gu ide.pdf

[Ged Leitch]

Chris Cavell wrote on Wed, 24 August 2005 20:57

Gerald, here are links to the Pro Tools Reference guides for your viewing pleasure...check the areas I have pointed out to you in my previous post...this is the documentation you've been seeking:  http://akwww.digidesign.com/support/docs/69/Pro%20Tools%20Re ference%20Guide.pdf  http://akwww.digidesign.com/support/docs/PT_6.4_Reference_Gu ide.pdf

Cheers for the links Chris, though already had the pdf.
Checked it out and...oh well, I stand corrected I've had tools for years and use HD2 at studio and totally over looked that paragraph!
Always thought internaly it was working at 24bit as Digi don't make an issue of this other than a small paragraph in the pdf.
Thanks again.

[Ged Leitch]

Does'nt say whether it dithers output to 24 bit or truncates though?

[Chris Cavell]

I'm not sure what it does...

I don't think it dithers though...

If you were to bounce a sine wave, then import it back into the session, flip the phase of one, and play them back...if it dithered, shouldn't there be a little noise down around -140dB?  In LE, if you do this, there isn't any (remaining ultra low level noise that is).

[dongle]

high guys, dont feel bad for highjacking, this is a topic im much interested in, i mean the avenue you goes went down. I must say im boggled now, i thought tdm was 48bit fixed. Im gonna give up on this. Its one big mind f@#k, bloody digidesign, they could market terds effectly with there cunningness, and skull duggery.   So what was the final highjack result guys.

[Ged Leitch]

dongle wrote on Wed, 24 August 2005 22:38

high guys, dont feel bad for highjacking, this is a topic im much interested in, i mean the avenue you goes went down. I musted say im boggled now, i thought tdm was 48bit fixed. Im gonna give up on this. Its one big mind f@#k, bloody digidesign, they could market terds effectly with there cunningness, and skull duggery.   So what was the final highjack result guys.

Hi Dongle, turns out that P.tools IS in fact 32 bit float internal BUT 24 bit on the output.
BUT wait...none of that still answers your orig question as to why the same wav in samp and P.tools sounds different so sorry man.
I think it has to be the way both programs are written to handle the audio (i.e the algorithms) it's all I can guesstimate at this time.
By the way have you tried the sonalksis 315 comp yet dongle?
I think you'd like it

[dongle]

No i havent, il see if i can get a look at a demo, thanks for the tip. Hows the comp windup going man. With pt being 32 float and 24 at the output does that mean it would be a good idea to dither to the 24th bit, say when finished with a mix, put an insert in the master fader, dither set to 24 bits. Also is HD 48 fixed, cause didnt you say you read that it is something else. Thanks guys

[Ged Leitch]

dongle wrote on Wed, 24 August 2005 22:49

No i havent, il see if i can get a look at a demo, thanks for the tip. Hows the comp windup going man. With pt being 32 float and 24 at the output does that mean it would be a good idea to dither to the 24th bit, say when finished with a mix, put an insert in the master fader, dither set to 24 bits. Also is HD 48 fixed, cause didnt you say you read that it is something else. Thanks guys

Nearly finished the comp test...
if you mean when finishing a "mix" e.g a song, then in theory as the internal process is 32bit float then technically you should dither on output to 24bit - but this is only speculation as I am not certain whether pro tools dithers itself to 24bit or truncates.Chris said he tested this in LE without dither on the output but noticed no additional noise.So I would say it's not needed.