I'm using SONAR Producer v 8.5.2.222
 
I recently was checking a finalized exported mix by opening the stereo .wav file in Adobe Audition.  I noticed noise in the quiet places (like the ending fade) at around -66dB on the Audition meters.  Wondering if it was something in the recording, I created a new project, and with only one track and no busses, effects, etc. I recorded several seconds of silence at 44.1\24.  I then opened the resulting file in Audition.  You can magnify the amplitutde of the wave, and the recorded file was abolutely quiet up to the maximum magnification (scale begins at -150dB).  I then  exported the recording like I would a finished mix, using File\Export\Audio and made the settings 44.1\16\Pow-r 3.  The resulting output does indeed have consistent noise that hovers between -69 and -63.  At that level it is absolutely audible above the self noise of my monitors.  I tried the same thing again, but I used Pow-r 2 and Pow-r 1 instead.  The resulting files have noise that hovers between -81 and -75.  This is a significant difference!  The noise is barely detectable above the noise floor of my monitors, and rather than being louder, it is just a different color.
 
Can someone please confirm my findings?  Just record a silent track at 44.1\24 and export to 44.1\16 using Pow-r 3 and do another export with Pow-r 2 and compare the results.  I can add plenty of audible noise to my recordings on my own.  I don't need the dithering tool to do it for me :)
 
Thanks,
 
Poco
 
P.S. I am familiar with the manual.  I have searched the forum (much information about dithering there.  Some good some not.  Nothing on this specific issue)...

I've found odd issues with Pow-r 3 when I use it to make a master.  I usually record / mix using Pow-r 1.

since the last update, I think Pow-r 3 no longer does what it should do.. and quite frankly not so happy about it.   I'm guessing I'm going to have to try Pow-r 2 or use Pow-r 1...

I'm going to watch this thread.

A while back I did some preliminary mastering on some tracks in Sonar before sending them out & found I didn't care for Pow-r-3 as most seem to.
Actually thought triangular setting had a bit cleaner sound on my stuff.

I'll watch this thread too, I'd like to read any other results or comparisons to Poco's.

This should get interesting...
 
I noticed this a while back, and have been meaning to look into it. I thought dither was just supposed to "wiggle" the last bit, which would give it an amplitude of only -90dB in a 16-bit export by my calculations. I also get amplitudes around -65dB with Pow-r 3, but even Pow-r 1 seems excessive. I don't know a lot about dither (obviously), but -65dB can't be right.

From my understanding, the numbers everyone is seeing are correct.  The problem is we're looking at dither in silence.  Silence is the time when dither is useless.  Dither is supposed to help with quiet parts, not silence.  It can allow a 16 bit signal to be perceived, without distortion, below -96dbFS...even through the dither "noise".  It's a bit of trickery.  It's not just any noise, though.  Sure, ones like Triangle look more like constant noise across the whole frequency range, but Pow-r is filtered/shaped.  Pow-r 3 is seen as the "preferred" of the choices because of it's shape that drops around 3k, an area we are most sensitive, and the loudest frequencies are above 10k.  Here is a look at a few(I just did these):

Blue: Triangle     Green: Pow-r 1     Orange: Pow-r 2     Purple: Pow-r 3

Notice the top of the graph is -90db.  I left the stats up for Pow-r 3 so you can see, yes, it does get into the -60s, peak.

Most of this is summed up from the Bob Katz "Mastering Audio" book.  He gets into Pow-r on pg. 59(2nd Edition) and there are pics that mirror what you see above.  Which kind to use still seems to come down to what you think works best for the current project.  There are options out there for dealing with the silence(think gated dither) but not in Sonar.  Well, hopefully that helps some.
 
Too tired to go on...please correct me if I'm wrong.
Forgot to add...I'm using 8.5.3.

From my understanding, the numbers everyone is seeing are correct.  The problem is we're looking at dither in silence.  Silence is the time when dither is useless.

That's correct. Measuring it with silence is useless. Dithering is suppose to add noise (distortion)
when you have noise, it lessens the audibility of the digital distortion that you get when you quantized errors. The low level hiss sound  is traded off for a reduction of digital distortion.
CJ

Well, hopefully that helps some.

Yes. Thanks. Makes sense, and I'm glad you were able to put this thread to bed early.


Still a little surprising that the higher frequency components are at such a high level, and I kind of wonder what happens when you run it through an MP3 encoder. Is it still better than no dither in terms of the character of the noise that results?

@bil_g
 
Many thanks for your help.  However...
 

The problem is we're looking at dither in silence. Silence is the time when dither is useless.

 
To me, the bigger problem is that in that silence, you can actually hear it!  If my client asks me why there is noise in his recording and I give him some tech speak about dithering, that will not get me too far.  To him (and me) it's still just a digital recording that's reminiscent of a cassette tape :)  And I can guarantee you, he is expecting digital perfection in his recording, a part of which is dead quietness where it is most noticeable, i.e the silent places.  We spend huge amounts of money to purchase equipment that does not add noticeable noise to our signal chain, then we wreck that effort intentionally by using a dithering method that is clearly audible.  Hmmmmmm.
 
FWIW, it looks like I will be using Pow-r 2 from now on.  It just creeps me out to see meters dancing significantly where there should only be silence.  My monitoring is at least as quiet as the better home stereos which assures me that if I can't hear dithering noise, neither can my client.  For those of you that can't hear it, it may be that the noise floor of your monitoring is too high (no offense intended).  -60s is actually pretty noticeable, especially when compare to complete silence.  Even at -75 (Pow-r 2) I am tempted to go into my 16 bit finals and "clean them up".  Silence should be just that.
 
P.S. I have read Bob Katz' article on dithering.  What I did not expect was for my less than perfect system to so easily detect the dithering signature.  I wonder how many commercial releases have the same signature?
http://www.digido.com/dither.html

  For those of you that can't hear it, it may be that the noise floor of your monitoring is too high (no offense intended).  -60s is actually pretty noticeable, especially when compare to complete silence.

Also no offense intended, but I think you need to check the rest of your signal chain. I just did a little testing, and confirmed what bil_g's chart shows... that the dither signal level falls off significantly with decreasing frequency. Below 16kHz, the RMS level is down around -95dB (consistent with that one-bit wiggle I was talking about).


I don't know about you, but I know my 49-year-old ears can't hear those levels at those frequencies, even with monitoring levels cranked. The activity in your meters might be disconcerting, but I'd be really surprised if even teenage ears would notice it.

 Nope.  It's not my monitoring system, and my sample recordings are generated purely ITB - they are copletely silent, as my first post indicates.  When the sound coming from my RME 9653 goes from a silent part of the waveform to the part where the dithering noise is I can definitely hear it.  To create the silent part, I took the rendered waveform and silenced sections of it use Audition.  Since I can hear the difference, it has nothing to do with my equipment, unless of course, it's designed to accentuate dither.  I don't think RME had that in mind :)  The levels are cranked pretty loud to hear it, but not above what my JBL 4410's can handle with regular program material at that volume.
 
If you can't hear it, you may want to check your system's self noise.  It may be masking the dither noise.