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R/E/P => R/E/P Archives => Brad Blackwood => Topic started by: dongle on August 23, 2005, 03:09:51 am

Title: Please Explain (PT vs. Samp)
Post by: dongle on August 23, 2005, 03:09:51 am
Hi guys, i need some help from you guys, this is beyond me. I took a stereo file of a mix, and used the rcomp, linmb then the l3 in protools, then i bounced the file. I did the same thing in Samplitude pro 8 and compared the two, and they were quite different. I know that le is rtas, and i was using Direct X in samplitude, but the i didnt think there would be much this much of a difference, in favour of Samplitude. Should this be the case, do some programs process plugins more effectively than others.
Any help is appreciated.
Thanks
Title: Re: Please Explain
Post by: Ged Leitch on August 23, 2005, 04:20:20 am
dongle wrote on Tue, 23 August 2005 08:09

Hi guys, i need some help from you guys, this is beyond me. I took a stereo file of a mix, and used the rcomp, linmb then the l3 in protools, then i bounced the file. I did the same thing in Samplitude pro 8 and compared the two, and they were quite different. I know that le is rtas, and i was using Direct X in samplitude, but the i didnt think there would be much this much of a difference, in favour of Samplitude. Should this be the case, do some programs process plugins more effectively than others.
Any help is appreciated.
Thanks


it depends on a lot of factors...
were the plugin settings RXACTLY the same on each program?
are you listening to the two wavs through the same monitor system?
did you dither as the last step after L3 (or using its own} if you were giong from a higher bit depth file (24bit for example) to 16 bit?
cheers.
Title: Re: Please Explain
Post by: dongle on August 23, 2005, 04:34:16 am
Hi Gerald, i saved the settings as presets, remained at the same bit depth saple rate everything the same.Also same room, speakers Both programs are 32 float, Is it possible for certain sequencers to process plugins more effectivly than another, even though they are both processed at the same bit depth.  Thanks guys, I dont know where else to go for this type of info.
Title: Re: Please Explain
Post by: Ged Leitch on August 23, 2005, 04:38:21 am
dongle wrote on Tue, 23 August 2005 09:34

Hi Gerald, i saved the settings as presets, remained at the same bit depth saple rate everything the same.Also same room, speakers Both programs are 32 float, Is it possible for certain sequencers to process plugins more effectivly than another, even though they are both processed at the same bit depth.  Thanks guys, I dont know where else to go for this type of info.


thats weird I always thought pro tools was 24 bit.
Anyway I can't really think why the two sound different if their both processed using the same settings other than how efficient either program handles the processing tasks.
sorry man Sad
Title: Re: Please Explain
Post by: dongle on August 23, 2005, 04:48:56 am
No worries, im not 100% about pt being 32 float, i just presumed it was, can anyone confirm, also is there much difference.
Thanks.
Hey Gerald how the compressor windup winding up.
Title: Re: Please Explain
Post by: Ged Leitch on August 23, 2005, 04:54:11 am
dongle wrote on Tue, 23 August 2005 09:48

No worries, im not 100% about pt being 32 float, i just presumed it was, can anyone confirm, also is there much difference.
Thanks.
Hey Gerald how the compressor windup winding up.


Not finished it yet but keep an eye out...
im 98% sure p tools is 24 bit but I don't think it would make THAT much of a sonic difference if the setting were all the same, more likely it's how the programs are written and how efficient each is.
Cheers.
Title: Re: Please Explain
Post by: bblackwood on August 23, 2005, 05:40:04 am
Was it PT or Digi001/2?
Title: Re: Please Explain
Post by: dongle on August 23, 2005, 05:53:32 am
002 rack
Cheers
Title: Re: Please Explain
Post by: bblackwood on August 23, 2005, 06:01:33 am
IIRC, only the TDM rigs are 24 bit (processing at 48 fixed), so the 002 should be 32-float, like Samplitude...
Title: Re: Please Explain
Post by: dongle on August 23, 2005, 06:16:39 am
bblackwood, Does it sound strange to you that i obtained these results.
Title: Re: Please Explain
Post by: bblackwood on August 23, 2005, 06:21:34 am
Sounds like something's amiss to me - all settings being equal they should sound the same (unless there is some underlying fundamental issue one program has that the other doesn't, but I don't think that's the situation here).

Can you host the two files somewhere (preferably named something like A and B so we don't know which is which) for us to listen to? A 30 sec snippet of each track should suffice and won't be very big...
Title: Re: Please Explain
Post by: dongle on August 23, 2005, 06:57:31 am
I appreciate the offer but i wont waste any more of your time. if you guys think it doesnt seem normal then it probably caused by me or by my hardware, ive had nothing but probs with my 002 since day 1 its been sent back 2 times within 6 months, and it takes 5 weeks each time i send it away to get it back, my bloody m-box has been more reliable, the second time, the dealer who i bought it off gave me a loan 002, only cause ive spent so much money there and hes afraid of losing my business, and it was solid as hell. The guy at the store who is a digi rep said the 002's have been quite flawless,but he actually told me that there was a slightly defective batch that were sent out to be sold knowing that they werent up too scratch. Which is great when youve just paid 2grand aus for 1 and its stuffed from the get go, I took it back and they say, sorry digidesign policy, no refund, no exchange, and we dont have any spare for you to take in the mean time.  but i was basically after a (yeah Samplitude has a reputation of being a lot more stable an so forth), or the answers you guys have given, which leads me to believe, either, a=im the prob, or b=my system, ill do a norton ghost clean up the pc fresh install, things like that conduct the test with m-box, and 002, see what happens. I got an error during playback the other day in Pt which ive never seen before, which had something to do with inaccurate clock source, I know that aint good, and i havnt done anything out of the ordinary to achieve this. but like i said just hearing what you guys had to say about it is enough to ensure me that the difference should not be noticable. Also im embarrassed for you pros to here my own work. I think a daw shootout is in order. Anyone interested, ill do my bit, but thanks for your time guys. After performing somemore tests ill see what happens. Is anyone interested in a Daw comparison of some sort, i know it could be difficult, but i think it would be worth while to put these rigs through the ropes, mixdown a song through various daw with same plugins and so fourth i could do an le test with m-box and 002, that is if you trust my 002. Cause im a bit tired of heresay when it comes to the performance of these system against each other, like hd vs levs nuendo vs cubase vs sequoia and so on. Sorry for the long post, and thanks again for your replies.
Title: Re: Please Explain (PT vs. Samp)
Post by: OTR-jkl on August 23, 2005, 08:15:53 am
Did you try a null test to make sure that they really are different and you're not just imagining it...? (It does happen, ya know...)
Title: Re: Please Explain (PT vs. Samp)
Post by: dongle on August 23, 2005, 08:31:00 am
Nah, i didnt need to cause the difference was too obvious. But ill do some soon, with different songs. I have to make sure my gear or drivers are not conflicting with either pt's or samplitudes performance, too get to the bottom of this.
Thanks Man
Title: Re: Please Explain (PT vs. Samp)
Post by: Bob Olhsson on August 23, 2005, 09:02:33 am
How exactly are you listening to the bounced files?

Samplitude dithers the reduction to the drivers while PT LE doesn't. Did you try disabling Samp's dither and just use the L3?

I use both every day and haven't noticed that much of a difference but this is only when I'm carefully comparing apples to apples. One difference has been that Samp's PowR 3 dither occasionally seems a bit brighter than PTle's.
Title: Re: Please Explain (PT vs. Samp)
Post by: dongle on August 23, 2005, 10:08:23 am
Hi bob no i havnt tried that ill give it a go, does Samplitude apply dither automatically, or does it apply the dither for reduction from 32 float to 24 bit, also, are you using samplitude for mixing or mastering, or both. Samplitude feels more stable in realtime playback, it just feels like its processing the plugs better, but that could be just crap aswell, what do you think bob.
Thanks
Title: Re: Please Explain (PT vs. Samp)
Post by: Chris Cavell on August 23, 2005, 10:12:34 am
Possibly the result of different pan laws through the summing buss?
Title: Re: Please Explain (PT vs. Samp)
Post by: OTR-jkl on August 23, 2005, 10:23:47 am
dongle wrote on Tue, 23 August 2005 09:08

does Samplitude apply dither automatically,

No. Dithering options in Samp are found by clicking on the Output assignment button on the Master buss.
Title: Re: Please Explain (PT vs. Samp)
Post by: MT Groove on August 23, 2005, 10:28:38 am
Chris Cavell wrote on Tue, 23 August 2005 15:12

Possibly the result of different pan laws through the summing buss?


That would be my guess as well.  
Title: Re: Please Explain (PT vs. Samp)
Post by: dongle on August 23, 2005, 10:55:24 am
Thanks for all your help guys. Much appreciated to receive replies.
Title: Re: Please Explain (PT vs. Samp)
Post by: Ronny on August 23, 2005, 12:01:04 pm


Usually when differences like this show up when they aren't supposed to, it's attributable to pilot error. We all make mistakes and most commonly the routing matrix selected.


WRT, panning law. Panning law is panning law, there aren't multiple types of panning law, however consoles deal with panning law differently. For example the older SSL's allowed you to vary the panning dB's, to accommodate the distance of speakers to sweetspot, for example nearfields -3dB and farfields -4.5dB. Typically though with most consoles it's - 3dB, from hard pan to center. Some consoles allow disabling the adjustment for pan law and don't attenuate the channel when going from hard to center, but anytime that pan law enters the equation of making your two examples sound different than it's going to be a + or - 3dB differene. That's easy to measure with an analytical too, but your ears should hear the gain difference immediately if pan law "adjustment" is a factor.  
Title: Re: Please Explain (PT vs. Samp)
Post by: Bob Olhsson on August 23, 2005, 03:22:59 pm
I'd call Samplitude semi-automatic in that you can disable dither. It defaults to on when appropriate. Pro Tools LE defaults to no dither. As far as I'm concerned, the Samplitude folks got it right because thinking about dither is sort of like thinking about tape bias. One OUGHT to not need to think about it beyond simply making sure it's adjusted optimally for the output format.
Title: Re: Please Explain (PT vs. Samp)
Post by: dcollins on August 23, 2005, 04:38:08 pm
Ronny wrote on Tue, 23 August 2005 09:01


WRT, panning law. Panning law is panning law, there aren't multiple types of panning law, however consoles deal with panning law differently.



Of course there are actually many different panning laws!

Constant power, constant voltage, and somwhere-in between.

http://www.wavefront.mcmail.com/pan.htm

Is probably the best.

IIRC Neve's just slugged linear pots to make a panner, no opamps.

DC
Title: Re: Please Explain (PT vs. Samp)
Post by: Ronny on August 23, 2005, 05:21:06 pm
dcollins wrote on Tue, 23 August 2005 16:38

Ronny wrote on Tue, 23 August 2005 09:01


WRT, panning law. Panning law is panning law, there aren't multiple types of panning law, however consoles deal with panning law differently.



Of course there are actually many different panning laws!

Constant power, constant voltage, and somwhere-in between.

http://www.wavefront.mcmail.com/pan.htm

Is probably the best.

IIRC Neve's just slugged linear pots to make a panner, no opamps.

DC


What would you call the effect? Pan phenonemon or something. I realize that there are different ways of addressing the effect and what you are calling panning laws, but aren't they all  relative to the one physical law that deals with increased gain when doubling the source output? I'm talking about the phenomenon and you are talking about variables to address the phenomenon.
Title: Re: Please Explain (PT vs. Samp)
Post by: mdbeh on August 23, 2005, 05:41:41 pm
Ronny wrote on Tue, 23 August 2005 16:21

What would you call the effect? Pan phenonemon or something. I realize that there are different ways of addressing the effect and what you are calling panning laws, but aren't they all  relative to the one physical law that deals with increased gain when doubling the source output? I'm talking about the phenomenon and you are talking about variables to address the phenomenon.



Calling them panning laws is standard, and it's a really basic area:

 http://www.eqmag.com/story.asp?sectioncode=41&storycode= 7672

Title: Re: Please Explain (PT vs. Samp)
Post by: Ronny on August 23, 2005, 05:57:10 pm
mdbeh wrote on Tue, 23 August 2005 17:41

Ronny wrote on Tue, 23 August 2005 16:21

What would you call the effect? Pan phenonemon or something. I realize that there are different ways of addressing the effect and what you are calling panning laws, but aren't they all  relative to the one physical law that deals with increased gain when doubling the source output? I'm talking about the phenomenon and you are talking about variables to address the phenomenon.



Calling them panning laws is standard, and it's a really basic area:

  http://www.eqmag.com/story.asp?sectioncode=41&storycode= 7672




I've already read the eqmag description. I should rephrase to say phenomenon for lack of a better word.
Title: Re: Please Explain (PT vs. Samp)
Post by: dongle on August 23, 2005, 06:53:49 pm
Hi guys, with regards to these panning laws, i read the article it said some Daw give you the option of changing the panning "law".
Can this be done in protools. Also If i have a lot of panning automation during a mix, could this result in different bounces. Also it seems best to me to minimise the amount of panning one should do in a mix.
Cheers
Title: Re: Please Explain (PT vs. Samp)
Post by: tweakman on August 23, 2005, 08:41:42 pm
First time post! after months of lurking . . Embarassed
Great forum Brad!.

"Bouncing" in ProTools LE "colors" the sound and not in a good way. (a more narrow stereo field, looser bottom end and a little harsher on the top end.)Also if you're editing a stereo mix and have crossfades,  don't "consolidate" the track because that too degrades the sound. ("consolidate" in PT HD seems better).
It's better to go real time via spdif to Samplitude/wavelab/etc on another machine or to an Alesis Masterlink. But If you only have one machine..
Try this:
- Create a new seesion in PTs with two stereo tracks.
(with the mix's original sample rate and bit depth)

- Don't create a "Master Fader" just the 2 stereo tracks.

- On you're Mix track "insert" your plugins

- Route the output of your mix track to a Bus, say 1 and 2

- Set next stereo track's input to Bus 1 and 2 and it's output to hardware 1 and 2 and hit (alt+K)(option on mac) so you can monitor in play while being rec enabled.

- tweak your sound or recall the saved presets of the plugins you used in samplitude.. and when you're ready, hit record.

You will have your new files in the session's audio files folder in stereo split. (Don't process them to make them stereo interleaved)

Import these files "as is" to samplitude in stereo split along with you're samplitude bounces and compare.. they should sound closer. Saying exactly the same would be hard because each program's sound engine sounds different.

whew!, well I hope this works better.. al least it does for me . . .

cheers
Title: Re: Please Explain (PT vs. Samp)
Post by: dongle on August 23, 2005, 09:35:39 pm
Took me a while to get it but that sounds like a good idea, am glad you have also noticed the dif with btd, Which option sounds best, summing all the outputs of a mix via bus, s/pdif out of 002 back into itself and record that, or record from 002 real time s/dif into m-box on another machine into samplitude realtime.
Thanks guys
Title: Re: Please Explain (PT vs. Samp)
Post by: dongle on August 23, 2005, 09:57:10 pm
Also does anyone know how to record realtime playback within Samplitude, Thanks
Title: Re: Please Explain (PT vs. Samp)
Post by: dcollins on August 23, 2005, 10:08:22 pm
Ronny wrote on Tue, 23 August 2005 14:21


What would you call the effect? Pan phenonemon or something.



Law is just another word for "curve" when talking pan-pots.

Quote:


I realize that there are different ways of addressing the effect and what you are calling panning laws, but aren't they all  relative to the one physical law that deals with increased gain when doubling the source output?



There are many factors, and just because two panners are 3dB down in the centre, does not imply any sort of standard throughout the whole range.

This shouldn't discourage anyone from panning, just that you can't really compare two tracks panned at "10 and 2" without knowing that they are same level.....

Analog or Digital.

DC

Title: Re: Please Explain (PT vs. Samp)
Post by: OTR-jkl on August 23, 2005, 10:14:25 pm
dongle wrote on Tue, 23 August 2005 20:57

Also does anyone know how to record realtime playback within Samplitude, Thanks

You can do it from track to track, but I've never gotten it to work right on my DAW.

The way I do it is to open 2 instances of Samp - use 1 for playback & the other for capture. Set the output of Samp1 (playback) to your soundcard dig out and the input of Samp2 (capture) to your soundcard dig in (you'll have to patch a loop). Set the output of Samp2 to your soundcard analog out. Turn Live Input on in Samp2, and hit Play. When you play Samp1, you will hear what Samp1 is playing (there will likely be a little latency). When you're ready to record, you can either hit Record in Samp2 or turn Mix-To-File on and hit Play and it will print directly to HD. Using this method, FX can be added on either instance. All FX on Samp1 will be printed. FX on Samp2 will only be printed if you use Mix-To-File.
Title: Re: Please Explain (PT vs. Samp)
Post by: dongle on August 24, 2005, 12:32:55 am
Thanks guys. Great resonses, love this site. Its so good to get decent answers.
Title: Re: Please Explain (PT vs. Samp)
Post by: Tomás Mulcahy on August 24, 2005, 04:33:27 am
FYI there were issues with the first batches of 002 rack and mixer. These manifested themselves in a variety of fun ways, and I would not be at all surprised if your audio quality issue was hardware related, even though it seems to be a software issue.

I have been using an LE/ 002 rack system recently with G5 and it sounds great. Bounce to disk in real time sounds perfect to me. 24 bit, no dither. I can't tell the difference between 32 bit float and 24 bit in PT. I certainly can in Cubase however!
Title: Re: Please Explain (PT vs. Samp)
Post by: brett on August 24, 2005, 09:42:38 am
Tom
Title: Re: Please Explain (PT vs. Samp)
Post by: Ged Leitch on August 24, 2005, 11:21:04 am
brett wrote on Wed, 24 August 2005 14:42

Tom
Title: Re: Please Explain (PT vs. Samp)
Post by: Chris Cavell on August 24, 2005, 12:24:15 pm
Quote:

Just read the pdf to double check, sorry man Pro tools LE is not 32 bit float it's 24 bit.


I don't know about the pdf...but plugin based bit meters say otherwise.
Title: Re: Please Explain (PT vs. Samp)
Post by: Ged Leitch on August 24, 2005, 12:27:37 pm
Chris Cavell wrote on Wed, 24 August 2005 17:24

Quote:

Just read the pdf to double check, sorry man Pro tools LE is not 32 bit float it's 24 bit.


I don't know about the pdf...but plugin based bit meters say otherwise.


Do you mean the plugins are 32bit? or are you reffering to P.tools LE DAW bit depth?
Title: Re: Please Explain (PT vs. Samp)
Post by: Chris Cavell on August 24, 2005, 12:41:09 pm
The DAW's bit depth.  Of course, you have to modify the signal in some way to register the float values on a plugin based bit-mater...a simple 0.1dB change in level on the mixer is enough to do that though...or throw in any plugin before the bit meter.

(The plugin's bit depth is dependent upon the individual design...but all RTAS plugs that I know of are *at least* 32 bit.)
Title: Re: Please Explain (PT vs. Samp)
Post by: Ged Leitch on August 24, 2005, 12:47:30 pm
Chris Cavell wrote on Wed, 24 August 2005 17:41

The DAW's bit depth.  Of course, you have to modify the signal in some way to register the float values on a plugin based bit-mater...a simple 0.1dB change in level on the mixer is enough to do that though...or throw in any plugin before the bit meter.

(The plugin's bit depth is dependent upon the individual design...but all RTAS plugs that I know of are *at least* 32 bit.)


heres a link for you to check out every other one i've checked says the same...
http://www.dolphinmusic.co.uk/d2/page/shop/news_story/a/news _id/e/14/a/r/e/google

also checked out the specs on the actual digidesign site, still got 24 bit processing not 32 bit float.
Title: Re: Please Explain (PT vs. Samp)
Post by: Ged Leitch on August 24, 2005, 12:51:25 pm
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.
Title: Re: Please Explain (PT vs. Samp)
Post by: TotalSonic on August 24, 2005, 01:00:16 pm
I think it's important when discussing a DAW's internal processing math to realize that often the bit depth of the temporary internal processing math can be different than the bit depth of the figure that is returned by such calculations.  From my understanding - in general current apps allow a plugin to do its internal processing math at its full level but then either dither or truncate the returned number to a lower level before sending it to the next process.  So a plugin with 64bit processing would indeed use that full math level no matter what app it was loaded in.  I believe in many cases whether the result is truncated or dithered depends on the plugin also.   So the question would be whether PT LE is sending either 24bit integer or 32bit floating point returned figures to the next process.  

Best regards,
Steve Berson
Title: Re: Please Explain (PT vs. Samp)
Post by: Ged Leitch on August 24, 2005, 01:05:59 pm
TotalSonic wrote on Wed, 24 August 2005 18:00

I think it's important when discussing a DAW's internal processing math to realize that often the bit depth of the temporary internal processing math can be different than the bit depth of the figure that is returned by such calculations.  From my understanding - in general current apps allow a plugin to do its internal processing math at its full level but then either dither or truncate the returned number to a lower level before sending it to the next process.  So a plugin with 64bit processing would indeed use that full math level no matter what app it was loaded in.  I believe in many cases whether the result is truncated or dithered depends on the plugin also.   So the question would be whether PT LE is sending either 24bit integer or 32bit floating point returned figures to the next process.  

Best regards,
Steve Berson


I can't seem to find any documentation on this, every page on the web i've tried so far say 24 bits and does'nt refer to whether the LE systems are sending 32 float in any process.
Title: Re: Please Explain (PT vs. Samp)
Post by: Ged Leitch on August 24, 2005, 01:08:14 pm
But hey this orig thread was from dongle wanting to know why samp or tools shows up differences with the same wav with the same settings on the processing and I'd rather not hijack his thread to start a debate on bit depths...
sorry dongle Sad
Title: Re: Please Explain (PT vs. Samp)
Post by: Bob Olhsson on August 24, 2005, 01:11:27 pm
There's a simple test for floating point operation.

Take a 16 bit source
Turn the volume up 60 dB past clipping
Turn the resulting signal back down 60 dB
Measure the number of bits in the output.

If it's floating point, there will only be 16 bits and the signals will null.

Pro Tools le passes this test. It only reads and writes 24 bit audio files and not 32 float so it's a good idea to dither the output to your files or output.

Digidesign just doesn't go out of their way to point out the advantages of le over TDM.
Title: Re: Please Explain (PT vs. Samp)
Post by: Tomás Mulcahy on August 24, 2005, 01:40:08 pm
What have I started? Funny though. Thanks Bob, as always, for your clarity.
Title: Re: Please Explain (PT vs. Samp)
Post by: brett on August 24, 2005, 01:56:20 pm
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.
Title: Re: Please Explain (PT vs. Samp)
Post by: Chris Cavell on August 24, 2005, 02:54:46 pm
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.


Title: Re: Please Explain (PT vs. Samp)
Post by: Ged Leitch on August 24, 2005, 03:24:19 pm
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.
Title: Re: Please Explain (PT vs. Samp)
Post by: Chris Cavell on August 24, 2005, 03:39:33 pm
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.
Title: Re: Please Explain (PT vs. Samp)
Post by: Ged Leitch on August 24, 2005, 03:48:31 pm
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.
Title: Re: Please Explain (PT vs. Samp)
Post by: MT Groove on August 24, 2005, 03:55:24 pm
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."  
Title: Re: Please Explain (PT vs. Samp)
Post by: Chris Cavell on August 24, 2005, 03:57:43 pm
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
Title: Re: Please Explain (PT vs. Samp)
Post by: Ged Leitch on August 24, 2005, 04:17:29 pm
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! Shocked
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.
Title: Re: Please Explain (PT vs. Samp)
Post by: Ged Leitch on August 24, 2005, 04:19:29 pm
Does'nt say whether it dithers output to 24 bit or truncates though?
Title: Re: Please Explain (PT vs. Samp)
Post by: Chris Cavell on August 24, 2005, 04:57:25 pm
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).
Title: Re: Please Explain (PT vs. Samp)
Post by: dongle on August 24, 2005, 05:38:44 pm
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. Twisted Evil  Twisted Evil So what was the final highjack result guys.
Title: Re: Please Explain (PT vs. Samp)
Post by: Ged Leitch on August 24, 2005, 05:43:22 pm
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. Twisted Evil  Twisted Evil 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 Very Happy
Title: Re: Please Explain (PT vs. Samp)
Post by: dongle on August 24, 2005, 05:49:04 pm
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
Title: Re: Please Explain (PT vs. Samp)
Post by: Ged Leitch on August 24, 2005, 06:02:21 pm
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.
Title: Re: Please Explain (PT vs. Samp)
Post by: Ged Leitch on August 24, 2005, 06:07:56 pm
To Chris...
"pro tools reference guide" page 473 para 2.

Quote" pro tools TDM systems processes all audio internally at 24 bit"
pro tools reference guide - page 546.

quote" pro tools TDM systems support full 24bit audio input and output signal paths,with 48 bit internal mixing and processing!"

confusing?...
Title: Re: Please Explain (PT vs. Samp)
Post by: Chris Cavell on August 24, 2005, 06:28:52 pm
It's been a really long time since I kept up with the innards of TDM, but it is my understanding that it works like this:

The summing buss is entirely 48 bit (or dual precision 24 bit).

All the insert points have fixed 24 bit single precision i/o streams (which made the master fader inserts function as expected, they're after the fader, and in TDM this means that the signal path after the master fader is 24 bit fixed).

Now here's where it gets confusing...and digi hasn't quite wrapped their heads around it themselves yet.

RTAS plugins need a 32 bit floating point I/O...so when they're placed on a track's insert, they change that insert point and all those that follow it on a given track to 32 bit float (AARGH!!!), and convert back to 24 bit fixed at the output of the last insert point.  This is why there are such huge restrictions regarding the placement of RTAS plugins in a TDM system...digi hasn't quite worked it out yet...but I'm sure they're doing their darndest to give the TDM guys just as much RTAS functionality as the LE guys.

When the audio comes out of the last insert point, it is passed as a fixed single precision 24 bit stream and placed in the middle of a dual precision 48 bit stream: the summing buss.  this leaves some empty bits above, and some below, leaving a pretty large amount of headroom as well as usually way more than enough lower bits to prevent quantization distortion within the mix buss itself.  The master fader then acts as a range selector across those 48 bits, choosing which range of 24 from within the 48 to send on to the master fader plugin section and/or on through to the converter.
Title: Re: Please Explain (PT vs. Samp)
Post by: brett on August 25, 2005, 09:21:05 am
Chris , thanks for communicating that so clearly. I was trying to explain it but wasn't doing a very good job. Didn't know the terminology, and wasn't confident enough to tell people they were worng, but this exact topic has gone around before. When I first starting using PT I was dumbfounded why you couldn't use RSTAS on the bus or Aux sends. It was that conversion reason from native to TDM that they didn't work out in earlier versions. I use 6.1 with mix plus. From what I remember on the DUC RTAS was implimented in 6.9 for HD users. Correct me if I am wrong.

Any computer tech will tell you, your native processes are at the native processing buss's speed. So when you were saying LE was 24, I wasn't buying it. With the advent of G5's and 64 bit pc's, we will see new software supporting 64bit float. Native looks better and better. I am interested to see how next generation TDM systems will work. I am sure they have 64bit cores on the way when people start looking to native, they bring that stuff to the forefront. Right now people are still buying HD systems. When the matket demands higher processing, the market will get it. 48 bit obviously works. There are plenty of high end digital hardware devices that use 48bit fixed.

As for the sound variance that started this thread, I say it again, the bus algorythms and sound are unique to software just like they are unique to any other mixer, beit analog or digital. The sound may be diferent from one app or hardware mixer to the other.

I can tell you from using Cubase 32 and then using Cubase SX years ago, I notice a marked improvement in my audio quality. They both processed at 32bit float and both recorded 24bit audio. The change was in the switch to the Nuendo mix architechture and audio engine. So when you say LE doesn't sound as good as a Samp bounce, I say leave it be and use Samp!!!!!!
Title: Re: Please Explain (PT vs. Samp)
Post by: Chris Cavell on August 25, 2005, 09:30:52 am
Quote:

From what I remember on the DUC it was implimented in 6.9 for HD users.


Digi has managed to slowly increase the RTAS functionality within their professional lines.  The "what can follow what" restrictions remain iirc, but you can now place rtas plugs on aux tracks (a big bold + for producers who use alot of softsynths and samplers).  I don't think you can put them on a master fader yet.
Title: Re: Please Explain (PT vs. Samp)
Post by: Bob Olhsson on August 25, 2005, 09:38:33 am
FWIW the only native Waves plug-ins that dither to 24 bits or less are the L-1 and L-2. L-1 has been double precision since I think version 4 which was when 24 bit dither first became an option.

I've had a hunch for 5 years that TDM will be replaced by some kind of a native co-processor scheme that gets around the latency issues. TDM is amazingly long in the tooth and 56k assembler code is prohibitively expensive to write.
Title: Re: Please Explain (PT vs. Samp)
Post by: TotalSonic on August 25, 2005, 09:42:10 am
brett wrote on Thu, 25 August 2005 14:21


Any computer tech will tell you, your native processes are at the native processing buss's speed. So when you were saying LE was 24, I wasn't buying it. With the advent of G5's and 64 bit pc's, we will see new software supporting 64bit float.


Brett -
It's important to note that buss speed is not the same as teh bit depth of an internal processing calculation routine.  You can easily have 64bit floating point math calculations done with a 32bit OS.  Theoretically the calculations will get done faster with the 64bit OS.  

Best regards,
Steve Berson
Title: Re: Please Explain (PT vs. Samp)
Post by: TotalSonic on August 25, 2005, 09:44:35 am
Bob Olhsson wrote on Thu, 25 August 2005 14:38

FWIW the only native Waves plug-ins that dither to 24 bits or less are the L-1 and L-2. L-1 has been double precision since I think version 4 which was when 24 bit dither first became an option.


L3 also has these same dithering options.

Best regards,
Steve Berson
Title: Re: Please Explain (PT vs. Samp)
Post by: Bob Olhsson on August 25, 2005, 09:47:55 am
true!

A lot of floating point processors operate at more than 64 bits too.
Title: Re: Please Explain (PT vs. Samp)
Post by: masterhse on August 27, 2005, 11:14:25 am
Gerald Leitch wrote on Wed, 24 August 2005 16:19

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


I believe that that is the main difference between the PT dithered mixer and non-dithered mixer.

Title: Re: Please Explain (PT vs. Samp)
Post by: Ronny on August 27, 2005, 11:44:16 am
masterhse wrote on Sat, 27 August 2005 11:14

Gerald Leitch wrote on Wed, 24 August 2005 16:19

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


I believe that that is the main difference between the PT dithered mixer and non-dithered mixer.




A word length reduction is a truncation, regardless of whether dither is applied or not. It's not either, I truncated or I dithered, being two opposing events, it's I truncated without dithering or I truncated with dither applied. A dithered word reduction is a truncation, because regardless of applying dither or not, you are still quantizing bit data.
Title: Re: Please Explain (PT vs. Samp)
Post by: masterhse on August 27, 2005, 12:47:00 pm
Ronny wrote on Sat, 27 August 2005 11:44


A word length reduction is a truncation, regardless of whether dither is applied or not. It's not either, I truncated or I dithered, being two opposing events, it's I truncated without dithering or I truncated with dither applied. A dithered word reduction is a truncation, because regardless of applying dither or not, you are still quantizing bit data.



True Ronnie, I assumed that the original post was a shorthand way of asking does PT dither before truncation.
Title: Re: Please Explain (PT vs. Samp)
Post by: bassman on September 05, 2005, 02:38:22 pm
Shamless plug here but when I come across these type of threads, I find the people that might be interested in what I do.  I am writing a book all about plug-ins and the DAW technology called "Plug-in Power: the Complete DSP Reference Guide" coming out this fall/winter.

<  http://www.amazon.com/exec/obidos/tg/detail/-/1592009530/qid  =1125588731/sr=8-2/ref=sr_8_xs_ap_i1_xgl14/103-6411458-44262 18?v=glance&s=books&n=507846>

I happened upon this thread doing research on pan law among other things and will have much information on this and other topics that come to the surface of the boards all the time.  Hopefully my efforts will consolidate much of this information and will be helpful to one and all wishing to improve their DAW audio results.

To add to the topic at hand, an earlier post described the PT bit depth chain and was accurate for the TDM systems. The plugins are connected by 24-bit busses and the mix buss is a custom scaled 48-bit systems that is reduced to 24 bit for output to the master plugins and analog converters. This is as per Bobby Lombardi, who handles plug-in design for Digi. I am double-checking all my info for the book as I go along...

PT LE is a native app and runs internally at 32-floating point until final output which MUST be reduced to 24 bit fixed point in order to be converted to analog!  This is something that gets confused often.  32-bit floating point files cannot be directly played back via analog converters.  Something must quantize the file to 24-bit fixed point in order to work.

Both fixed point and floating point math involves some errors during typical mixing. These errors crop up at different times and with different effects. I'm sure those differences will be debated as long as possible out here on the boards. Both systems are capable of tremendous work and if understood, can be maximized for each systems potential while avoiding any weaknesses.

The question I would like to add is unless you are using dynamic or moving pans in your mix, do you think that the pan law will truly effect the outcome? I believe it won't. If a sound is panned in one spot, you will adjust your level accordingly regardless of the pan law setting.

Now, importing and exporting between DAW's that have differing pan laws will surely change the sound, but if the pan law does not change, how does that affect the mix for non-moving sound sources?

-ashley shepherd