"It is all interesting stuff but for me personally I don't worry about it because there are far more important things to worry about in terms of getting a great mix than the summing procedure."
 
This all seems well and good, but when you are watching a tutorial and the presenter demonstrates that there is a stage that IS GETTING CLIPPED but you don't know it because you have to do a work around to have a meter run on a proxy of the signal I felt it was worth learning when and where to be aware that it may happen. I think it must have been referring to the TDM systems.
 
It has been difficult keeping track of which tutorials apply to the TDM systems, the HD, HDX, and native Software packages.
 
 
"And also if you adopt a K System approach to signal flow and have VU meters effectively telling you what the rms levels are everywhere in your system and the headroom built into that will also take care of any clipping or peaks then you will never have any issues with clipping on any track or buss or your masterbuss."
 
My OP question was a reaction to the fact that you don't have meters in the signal flow at the input of the summing busses and so you don't know what your head room is.
 
It is sort of a non issue as you can certainly place a meter as a first insert... but you still will not see it unless you go look for it.
 
The most important thing is to know if it is a possible issue. If it really is 32bit float now a days... then it is a non issue.
 
 
 
all the best,
mike
 
 
 

Working with 16Bit audio... way back in the very early days of PC DAWs (using the original version of S.A.W.), you could clearly hear the results of several stages of destructive processing (caused by rounding error).  For lack of a better description, the audio had a "buzzy" fuzzy like character.  Not pleasant.
 
I won't argue the fact that I could hear the difference between 32Bit Float and 64Bit dual-precision Float in a blind test.
But if you give me the 64Bit option... and it comes at virtually no CPU hit (on a fast modern CPU)... and it makes any thought of rounding error completely a moot point, why not take advantage?
 
I agree with Jeff that there are MANY other factors that contribute more to the quality of a mix.
Same with recording at higher sample rates...  (other factors have a greater impact on final results)
 

If you have a meter present especially first insert in line on a buss then the meter is showing you the sum of all the signals present on that buss. By maintaining the correct rms level on a buss then it means there cannot be any clipping or overload on that buss. (just out of interest Studio One has K metering options on the buses which is pretty handy, ie it is all built in. They have put it there because it is very useful)
 
I do it by not actually inserting a meter at all but by simply putting any buss into solo mode. My main VU meters are on the stereo buss but as I have all my busses sitting at unity then when a buss is in solo that exact signal is passed through to the stereo buss and hence my meter. The actual level of a buss is often lower than the reference level. Because several busses in my case may be used and will all sum together on the main stereo buss and that is where the final mix level reaches the reference level.
 
The idea of putting masterfaders in PT on the buses is interesting in that they can act as a metering device showing you signal level at those points.
 
There is no need to ever overload any buss in a multitrack digital recording system. If there is overload anywhere it means that something is simply wrong. All the tracks feeding that buss need to be grouped and dropped accordingly. The K system is a one way of keeping track of it all and it seems to work very well. If you use it there will be no overload anywhere and you will never hear distortion. The VU meters work well because even if the signal is just 3 dB over it looks way bad on the meter and very obvious. It alerts you very quickly. If the VU meters are working correctly then you are free to never worry about buss overload issues and hence you can focus on more important things.
 
The other thing about VU metering too is the ballistics. When things are working right the needle only just reaches 0dB VU and rarely goes over. If the meter swings wildly and even occasionally then it too becomes very visible and you need to go off and find the offending track that is causing it. Once you stabilise that signal then the VU meter on the buss will settle down again and only just reach 0dB VU as it should be. You won't see any of this with peak metering anywhere near as well.
 
It is good to know though that signals on busses can go over and there won't be an issue. I see that as a safety net, not the norm. My approach is to never let it happen in the first place.

Jim Roseberryut if you give me the 64Bit option... and it comes at virtually no CPU hit (on a fast modern CPU)... and it makes any thought of rounding error completely a moot point, why not take advantage?
 

Um, because in the real world it's already a moot point with 32 bits?
 
The truth is the only reason people think 32 bit is an issue is because some marketing folks used carefully worded language to imply that it is.
 
But I bet if you go back and carefully parse what they actually say, you'll see that they don't actually ever say that there's an audible difference - instead their very careful wording talks about errors in the abstract and leaves it to the reader to jump to the conclusion that those errors are a problem.
 
Now here's the question for you: If this stuff was really a problem, then why would they use that very careful, manipulative wording?

bitflipper
I'm dubious.

Will you be creating a new login then?
 
Can I have the bitflipper one?

mike_mccue
 
I know that SONAR uses a 64bit floating point mix engine. I love it.
 
I'm wondering what Pro Tools 11 native uses (the one with out the HD or HDX hardware) and I can't seem to Google up a clear answer.
 
 
Many of the older PT tutorials I am watching speak about clipping on aux inputs and a work around of inserting master faders to use as proxy input meters. I'm reflecting on how that sort of concern is pretty much a non issue with SONAR and its 64bit floating point engine.
 
Learning that people do this work around highlights my appreciation of the fact that SONAR can let you select either pre or post fader metering.
 
Is Pro Tools native up to par now or does 64bit floating point mixing require the more expensive HD option?
 
Thanks.
 
best regards,
mike
 
 

I cudda sworn this was the SONAR forum.
 
I gotta get more rest.

drewfx1

Jim Roseberryut if you give me the 64Bit option... and it comes at virtually no CPU hit (on a fast modern CPU)... and it makes any thought of rounding error completely a moot point, why not take advantage?
 

Um, because in the real world it's already a moot point with 32 bits?
 
 

Hmm...
 
I assume there's no penalty for using 64-bit floats - so why not uses them internally for buses. It appears Protools uses 32-bit floats for plugins because their HDX boxes use 32-bit floats and they want to to use identical algorithms on both host and native plugs. The precise machine instructions for these plugs will differ since since the host and DSP differ, but results should be identical. Not a bad goal.
 

drewfx1

Jim Roseberryut if you give me the 64Bit option... and it comes at virtually no CPU hit (on a fast modern CPU)... and it makes any thought of rounding error completely a moot point, why not take advantage?
 

Um, because in the real world it's already a moot point with 32 bits?
 
 

Hmm...
 
I assume there's no penalty for using 64-bit floats - so why not uses them internally for buses. It appears Protools uses 32-bit floats for plugins because their HDX boxes use 32-bit floats and they want to to use identical algorithms on both host and native plugs. The precise machine instructions for these plugs will differ since since the host and DSP differ, but results should be identical. Not a bad goal.
 

SuperGI assume there's no penalty for using 64-bit floats - so why not uses them internally for buses.

There's no reason not to use 64 bit; there's also no reason to use it in situations where there is no benefit.
 
It's a matter of keeping things in perspective - some things in the audio world are clearly audible and worth worrying about, while other things might be borderline audible at least some of the time. Other things will never be audible in the real world. And some people don't differentiate between the three while others of us do.

dmbaer
You can read the full story here, if interested:
 
http://soundbyte.arsov.net/Wordpress/2013/07/15/ofdigitalbitsanddecibels/

Very nice.  Thanks for this link.