for me, only 64bit floating point could defeat the 48bit (56bit actually) of Avid hardware mixing, with more than double bits of 24bit, extra dynamic headroom avoiding internal clippings, and can still keep full 24bit detail even through completely muted at the first stage but boosted back at the next stage, no any sounds lost. And also less rounding errors (like when 2 is going to be divided by 3, pi, or square root of 2). And finally, just kept all details inside 64bit, dithering from 64bit to 16bit so you can hear the incredibly unbelievable dynamic range and sensible SNR........

mettelus
SONAR/CbB (in fact, any DAW) has to drop to 24-bit to get out your audio interface and everything associated with that is automatic. The internal word length is for computational accuracy. You do not need to dither to export a pre-master, 24-bit track.

As mentioned above, the only dither is when going to final 16-bit, CD print.

Actually...the LG V30 has a seperate 32bit DAC - neat.

For me, 64 bit fp all the way. There are a number of reasons - some have been mentioned, but you lose definition, particularly the analouge emulation effects if you don't record, mix and master at 64bitfp. The bottom end gets all grainy. Granted 32bit fp is better than 24bit and worse 16 bit...but it's quite amazing at what you lose if you don't convert from a 64bitfp master audio file to whatever your distribution medium is. I'm not sure what your burning program is, and that could be an issue - because some silly sausages in the industry still wholeheartedly embrace the 24/16 bit paradigm.

Of course there's a cavet to 64bit fp. Say you're doing a straight forward troubadour type track or even a lo-fi rock band (do they even exist anymore?) 😊😎 you could probably get away with a lower bit depth - because you're not using a huge amount of time based effects (rounding errors and the like). Also if you're sending audio in and out of the box...including during mastering...then the benefits of 64bit audio is almost totally lost. 64 bit fp audio and mix engine allow you to mix in the same fashion as the rock-avant-gardes i.e. in the red.

Ben

* Recording - whatever the audio interface produce, normally 24bit.
    - there is no interfaces which have meaningful 24bit resolution, but most of them are better then 16bit. The hint is in the specification: SnR or alike which is 96dB for 16bit (you can easily find that most interfaces have  over 100dB, but no of them have 144dB required for 24bit)
    - and so recording into 32 means saving at least 12 useless bits (into 64 format, ~44 bits pro samples will be useless)
* Processing - 64bit. Even simple mixing 2 channels "damage" the last significant bit, complex algorithms  use 1000s of mathematical computations. While that does not mean 10 operations always destroy last 10 significant bits, in practice that is much less, the result depends from the algorithm (usually moderate to good quality) and the programmer (experience of which in the music world is unpredictable). So the difference between 32bit and 64bit processing can shift into audible range (~16 bit). Note that up-sampling (f.e. to 96kHz) in some situations sounds "better" (you can find some examples from Craig) for the same reason.
* Intermediate saving (rendering/mix export/etc) - 32bit. That is "floating point" format with 24bit precision bits for any number. Even in worse case scenario, it will take ~8 intermediate savings till the difference to 64bit become audible (so you process -> export -> import -> process -> export -> import ... etc). I have not seen examples in the Internet that such degradation ever happens in practice. Note that 24bit format is fixed point, that means low amplitude samples have low precision (down to 1bit!) and only full amplitude samples have 24bit precision. The degradation is 1bit loose pro ~6dB. F.e. if the upper level of samples in your rendered file is -18dB, you use at most 21bit when exporting into 24bit format.
* Master output - 24bit or 32bit. After mastering the level should be normalized. Future processing is not going to increase the level of low amplitude samples, it will only reduce the precision when moving toward 16bit CD format. So 24bit fixed point is more then sufficient.
 
Finally. Dithering should be applied only once, especially "good" algos (noise shaping). By definition of that process, dithering adds noise to the signal (that is a trade, not a magic, you get more noise for less quantization distortion, a good trade for listening but questionable for future processing).  

many experiments show that, even through the case you convert 16bit into 32bit then send into a 32bit digital fader, then dither down to 16bit output again, the Signal-Noise-Ratio and dynamic range is still much larger than the cast you just send 16bit into a 16bit fader only.
 
That's why you should always enlarge the bit depth of internal rendering, processing and inter-processing.

Use an 8 track, one-inch tape machine instead of 16 heads.  And mix down to a half-track, 1/4-inch tape, not a 1/4- inch, quarter track.  More sound per square inch of tape.  Almost like higher bit depths and sample rate.  Always keep your resolution at the max for each step.

Interesting discussion.  So, wouldn't it be easiet to simply master inside a project then?  Therefore you can simply export to 24 (or to 16 with dither) just ONE time, and all the internal processing remains at whatever the global default render depth is set to.  This eliminates the need to worry about the various settings along the way. And if you want to toggle between mix and mastering work simply disable the FX bin on the mastering bus.  Assuming you have the CPU power it sure seems like this approach is a lot easier than trying to break things into different steps (mix, master, dither/CD) using separate templates and/or different software hosts.
 
Sonic
 
 

SonicExplorer
Interesting discussion.  So, wouldn't it be easiet to simply master inside a project then?  Therefore you can simply export to 24 (or to 16 with dither) just ONE time, and all the internal processing remains at whatever the global default render depth is set to.  This eliminates the need to worry about the various settings along the way. And if you want to toggle between mix and mastering work simply disable the FX bin on the mastering bus.  Assuming you have the CPU power it sure seems like this approach is a lot easier than trying to break things into different steps (mix, master, dither/CD) using separate templates and/or different software hosts.
 
Sonic
 
 

I do exactly this

Bristol_Jonesey

SonicExplorer
Interesting discussion.  So, wouldn't it be easiet to simply master inside a project then?  Therefore you can simply export to 24 (or to 16 with dither) just ONE time, and all the internal processing remains at whatever the global default render depth is set to.  This eliminates the need to worry about the various settings along the way. And if you want to toggle between mix and mastering work simply disable the FX bin on the mastering bus.  Assuming you have the CPU power it sure seems like this approach is a lot easier than trying to break things into different steps (mix, master, dither/CD) using separate templates and/or different software hosts.
 
Sonic
 

I do exactly this

Which is the better dithering approach in this setup....use a dither option in a mastering plugin or rather from Sonar's export menu?

azslow3
* Recording - whatever the audio interface produce, normally 24bit.
    - there is no interfaces which have meaningful 24bit resolution, but most of them are better then 16bit. The hint is in the specification: SnR or alike which is 96dB for 16bit (you can easily find that most interfaces have  over 100dB, but no of them have 144dB required for 24bit)
    - and so recording into 32 means saving at least 12 useless bits (into 64 format, ~44 bits pro samples will be useless)
* Processing - 64bit. Even simple mixing 2 channels "damage" the last significant bit, complex algorithms  use 1000s of mathematical computations. While that does not mean 10 operations always destroy last 10 significant bits, in practice that is much less, the result depends from the algorithm (usually moderate to good quality) and the programmer (experience of which in the music world is unpredictable). So the difference between 32bit and 64bit processing can shift into audible range (~16 bit). Note that up-sampling (f.e. to 96kHz) in some situations sounds "better" (you can find some examples from Craig) for the same reason.
* Intermediate saving (rendering/mix export/etc) - 32bit. That is "floating point" format with 24bit precision bits for any number. Even in worse case scenario, it will take ~8 intermediate savings till the difference to 64bit become audible (so you process -> export -> import -> process -> export -> import ... etc). I have not seen examples in the Internet that such degradation ever happens in practice. Note that 24bit format is fixed point, that means low amplitude samples have low precision (down to 1bit!) and only full amplitude samples have 24bit precision. The degradation is 1bit loose pro ~6dB. F.e. if the upper level of samples in your rendered file is -18dB, you use at most 21bit when exporting into 24bit format.
* Master output - 24bit or 32bit. After mastering the level should be normalized. Future processing is not going to increase the level of low amplitude samples, it will only reduce the precision when moving toward 16bit CD format. So 24bit fixed point is more then sufficient.
 
Finally. Dithering should be applied only once, especially "good" algos (noise shaping). By definition of that process, dithering adds noise to the signal (that is a trade, not a magic, you get more noise for less quantization distortion, a good trade for listening but questionable for future processing).  

You obviously didn't read my post, because it's about rounding errors and internal dynamic range. Those bits aren't wasted in the mixing and mastering process. And who listens to 16 bit CD anymore anyway? I don't!. And you don't understand 64 bit fp masters for digital distrubutiin. I upload 64bitfp audio files to sound cloud at whatever sample rate I recorded too. So rather than a crappy 16 bit file that gets squashed....a 64bitfp HD audio gets squashed. No one gets digital conversion. If I could be bothered I'd write a paper on this...but as the old saying goes 'you can lead a horse to water, but you can't teach it to drink 64bit fp master files solves the HD audio problem. Even if you still only deliver a final 24bit master for actual listening. Which is the lowest format I use and listen too. Crapify has let the team down...instead of really sonically degraded audio files people listen to...with today's tech there should have been a 24 bit boom. Where all 24 bit commercial masters are delivered from 64bitfp masters. Again 64 bit fp solves the HD digital audio problem. It's more complex than than that...the secret sauce so to speak...but I can safely assure you that I could prove without a doubt that you the listener would never need a crap l.p. player or any other so called hi-fi equipment or even any over-priced analouge paper weight again - so long as people stuck with 64bit fp. I have the academic qualifications to say this!

Ben

Bristol_Jonesey

SonicExplorer
Interesting discussion.  So, wouldn't it be easiet to simply master inside a project then? Sonic
 

I do exactly this

I abandoned doing this a while ago, for reasons I'll explain below. It's more to do with work process than anything technical.
 
As a general point, I'd rather not master things I've mixed, but it frequently comes up just for budgetary reasons, so, you know, you do what you gotta.
 
However, I've come to think that keeping the line between mixing and mastering a very firm one is just a good practice. I think having the ability to easily tweak the mix while mastering is a bad process. And I'm increasingly trying to do less keeping my options open, and more making firm decisions as early in the project as possible.
 
I think my absolute nightmare scenario is something like this: we're supposedly in the mastering phase, but there's still a discussion going on about maybe changing the amp sims on the guitars. That's a deliberately extreme example, but in that case, you're not just not mastering, you're not even mixing, or close to done with the mix. You're still doing something more like arranging.
 
I want the process to be that we get to a mix all concerned are happy with, and that's signed off, and doesn't change. At that point, I'll take the 24 bit stereo render of that mix, and use that to master from. There shouldn't be any faults in the mix at this point. But on the other hand, there's no such things as perfect. So even if there are faults, you learn more, and develop skills more, by finishing things and moving on to the next thing. And leaving yourself a huge temptation to keep tinkering with stuff really leads away from that.