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#1
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Charlie Steinbergs take on Different sounding audio Engines
Hi,
I thought you might find this interesting; "the 'Logic sounds better' thing is not new and always comes down to pan law beeing 0 dB in Logic, as opposed to the defaults of -3dB in Nuendo and -6 dB in Cubase. this also explains why 'Nuendo sounds better than Cubase', because higher panning law makes centered signals (such as bass and bass drum) sound louder (= 'better') and 'more punchy'. one can argue either methods endlessly, i think the -3 dB default of Nuendo is a good compromise because most desks appear to use this. however punchy your mix sounds is entirely up to you, regardless of the panning law you choose; and if your mix sounds better when you switch to a different panning law, then you should think twice about how you mix in general at least, in Nuendo and Cubase, you can adjust the panning law so to fit your 'taste'. the idea behind -6 dB panning law is that when you would put your 2 stereo speakers into 1 box, wherever you set the pan, there wouldn't be any difference in volume (loudness), and this becomes obvious when you listen to the mix in Mono, because the sum of left and right when panning a channel is always equal. this is not true for any other panning law than 6dB. using 0 dB on the other hand, when you are all to the left or right, the sum will be 0dB, but when you pan to the middle it will become +6dB. personally this feels plain wrong to me (despite the math, just listening to it) and makes me insecure as to how much panning to apply, but it is really a matter of taste (and what you are used to; if you come from Logic, you'd probably be much better off choosing 0 dB). as said above, -3dB appears to be a good compromise, but whichever law you choose, your ears are the one and only final resort to jugde how 'punchy' you want your mix to be. Goobers perfect summing bus. (simplified example) Input from channel 1 =10 Input from channel 2 =3 Input from channel 4 =1 Add inputs together... Output= 14 Now, how could any data massaging algorhythm improve on this? All integer summing busses should sound exactly the same until ditherd. The only problem is that the VST engine uses a 32bit float, meaning that mixing large and small numbers could cause smaller signals to be lost due to mantissa priority confusion! sorry but this needs explanation... the nominal range of VST floating point is -1.0 to + 1.0. any signal going in or out the VST system is converted to this range. as 'external' signals are always integer currently, they are limited to maximum numbers (both positive or negative). so whatever the integer format (16 or 24 bit), the maximum and minimum values that those bits can represent are + 1.0 and -1.0 expressed in floating point terms. in a 32 bit floating point value, this will cover the mantissa of 24 bit, so it is always *at least* as precise as a 24 bit integer value (so it is at least 'as good'). the exponent is always 0. considering a signal of 0dB peak, this means the largest values will be + 1.0 and - 1.0 resp. smaller signals will go down to -144 dB with 100% precision, because the mantissa is 24 bits large (also there is a sign bit). going below -144 dB is also possible, where the farther you go, the less precise will the numbers become; not that this could ever have any impact, because a) there are currently and commonly no converters to deal with more than 24 bits nor b) is there any analog equipment that i know which can deal with dynamic ranges of over 144 dB anyways. only when you drive signals above 0dB will the exponent get changed. in this case the unbeleiveable headroom of the IEEE floating point mechanism becomes active. it works like a VCA: when you exceed 0 dB, the control voltage will rise, where below 0dB it will be constant (actually it changes to a negative 'voltage' when you get below -144 dB). as with the lower numbers, at a certain point, there is a loss of precision, but this is very small unless you go crazy with your signals. this gets us to This is where a small number dissapears when added to a larger one as the integer has too few bits to hold both values. I'm assuming they use a 24bit number with 7 bit mantissa and sign. It would have to a fairly extreme situation for this to happen, and I'm sure it could not be audible, but who knows? Using a floating point number may give better results for sperate channels in theory, but could cause problems when many are added. 'extreme situation', you can say that. for a signal of -140 dB to be masked, you would probably need some +140 dB on the other end. not only will this never happen in anybodys' studio (unless a plug goes mad , but even if it happened would you not really be able to hear that your -140 dB signal is gone, because your speaker mebrane has arrived at the opposite wall meanwhile. the bottom line of all of this is: - first off we are dealing with numbers. we don't want any colorizing so we 'only' need to be precise. maths can not be cheated. if any digital system sounds 'better' or 'worse' than another when playing back an unaltered signal and using the same hardware, either there is some bug, or there is colorization applied by intention. - second, the nominal range of 32 bit floats is always 100% precise within 144 dB (or 24 bits) (i think it's even 25 bits because we have an extra sign bit but it's late and i'm too lazy to look it up). - third, there is an incredible headroom with floats as opposed to integer values. there is loss of precision however when you exceed the range of the mantissa (those 24 bits), but that only happens when you exceed that range big time and even then, the change of the numbers that result is in the range of 1 bit which is again inaudible. and when you bring it all down again to the range that your converter can handle, the 'imprecise bits' usually fall outside that range anyways. - fourth and finally, there may be problems when *converting* those floating point numbers from and to integer numbers. we are currently double-checking this so to make sure that when you render to file (export audio), the outcome is exact. but even if we dumb programmers create errors in this area would you not be able to tell the difference (at least with 24 bit files), because again the error would be in the range of 1 bit, which is measureable but no equipment can reproduce it anyways. but yes, we certainly need to be 100% correct for your convenience and we will. that gets us to 'bus summing'. as somebody pointed out earlier, this is in fact nothing but adding values; and this adding operation is just as precise as your pocket (or scientific) calculator. would you trust it? BTW, Ksmith, did you hear about the test when the same tracks were summed in a PT Rig and the Oxford? The results could be put out of phase giving zero. http://www.virtualstudio.org/VS_AUTO...T/00-02-15/117 I think both PT and the sony use integer busses though. Either they both use the same 'summing bus' or we are all caught up in some invented problem. possibly How about a word from the people who write these things, Steinberg? No trade secrets, just perhaps some useful info to guide our ears. Is it better to mix with a fairly hot reading on the masters, or does that loose precision? Should we keep it fairly low and export the 32bit file to be normalised and ditherd? in theory, you should not overdrive the channels more than +6dB and of course keep your master at 0 dB. this puts you on the 'mathematically prooven exact side of the fence', so to speak. in practice, even if you drive many channels much into the red, it doesn't make for more than an inaudible (albeit possibly measureable) difference. actually, floats behave a bit like analog equipment: if you overdrive it, it does something on its own. but for what a float does then to become perceivable, you would have to write a plug which drives your signal up a few hundred dB's....certainly more than your analog tape recorder at +6dB, which is clearly audible. charlie"
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Yavuz AKYAZICI Guitar Player, Composer http://cdbaby.com/cd/volcano http://volcanojazz.com http://myspace.com/volcanojazz |
#2
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Re: Charlie Steinbergs take on Different sounding audio Engines
That was really cool.
By the way, what the hell did he say? [img]images/icons/confused.gif[/img]
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Soundsurfr MAC Mini, 2.3GHz dual-core i5, 8GB DDR3, 500GB Hard drive, 288MB DDR3 SD RAM M-Audio Firewire 1814 Yosemite OS |
#3
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Re: Charlie Steinbergs take on Different sounding audio Engines
I can't tell if I feel smarter or dumber after reading that. [img]images/icons/smile.gif[/img] [img]images/icons/confused.gif[/img]
I twist the pretty knobs and buttons till everything sounds "not sucky".
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"Sometimes I doubt your commitment to Sparkle Motion." BigRedButton / Jackson Jackson www.jacksonbjackson.com |
#4
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Re: Charlie Steinbergs take on Different sounding audio Engines
Quote:
In short, he was saying the different sounds of different DAW mixers are the result of the default panning gain. Otherwise they all add up numbers.
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Yavuz AKYAZICI Guitar Player, Composer http://cdbaby.com/cd/volcano http://volcanojazz.com http://myspace.com/volcanojazz |
#5
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Re: Charlie Steinbergs take on Different sounding audio Engines
Actually I would like to hear some comments on this subject form the PT programmers.
May be Brent? Because, This is really interesting.
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Yavuz AKYAZICI Guitar Player, Composer http://cdbaby.com/cd/volcano http://volcanojazz.com http://myspace.com/volcanojazz |
#6
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Re: Charlie Steinbergs take on Different sounding audio Engines
Interesting - Mr Charlie sais that a change of 1-bit is inaudible, but ends his message saying that a gain change of 6dB is very audible. There was me thinking that every bit reduced the noise floor by 3dB, and would therefore be audible.
He's right about the converters though - there are none currently available that give a true 24-bit dynamic range, this is due to their poor jitter performance. |
#7
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Re: Charlie Steinbergs take on Different sounding audio Engines
Vintech / Neve 1272's
Presonus MP20's (hot rodded) Bellari MP110 (occasionally for extreme color - mostly bass DI) Yamaha AW4416 preamps Very rarely the Digi 001 preamps Joemeek VC3Q's And yes, you CAN hear a 1 dB change... you can actually hear LESS than a 1 dB change in some circumstances...
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Phil O'Keefe PT 2023.6 Ultimate (Perpetual) | Avid Carbon | M1 Max Mac Studio; 32 GB RAM / 1 TB SSD, macOS 13.4.1 Ventura. PT 2023.6 Studio (Perpetual) | M1 MacBook Air; 16 GB RAM / 1 TB SSD, macOS 13.4.1 Ventura. |
#8
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Re: Charlie Steinbergs take on Different sounding audio Engines
Quote:
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Yavuz AKYAZICI Guitar Player, Composer http://cdbaby.com/cd/volcano http://volcanojazz.com http://myspace.com/volcanojazz |
#9
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Re: Charlie Steinbergs take on Different sounding audio Engines
Don't know about you guys, but I seem to spend a considerable part of my day in 'mantissa priority confusion'. [img]images/icons/wink.gif[/img]
Mark |
#10
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Re: Charlie Steinbergs take on Different sounding audio Engines
And I think that maybe this is why Rupert is Rupert and Charlie is Charlie...
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