Master Bus 48 Bit Mixer vs. PTT Summing

[DrFord]

Inspired by a post a few threads down, I went back and was reading old posts using the search function to the merits of using PTT vs. BTD. It seems them people felt the functionality was better with PTT for many reasons, but also that BTD had it's own merits such as truer automation and whatnot.

My question, is since the HD Master Fader uses a 48 bit mixer "plug-in" and any Aux or Audio tracks do not have this headroom, would it not sound better to BTD using the Master Bus/Fader?

Please don't post "search the forum" as that is what lead me to this question.

Thanks

D

[DrFord]

bump

[JFreak]

There's always a master fader, whether visible or not. Bouncing to outputs "A 1-2" will not sound any different than recording to "Buss 1-2" and then monitoring that 2-track via outputs "A 1-2". However, there seems to be some kind of a psychological myth about "1+2" being different than "1+2"...

Digital summing is pure math, there is no difference. All things being equal, digital summing produces exactly same results. Only moving part being reverbs and such, which will likely not produce same response every time. IF that "moving part" is included in the equation, you *can* make "1+2+X" sound different than "1+2+X" but it's only because "X" is different from time to time.

[Top Jimmy]

The whole mixer has the same 48-bit architecture, not just master faders. If you raise the level of a track up into constant clipping, any subsequent track can bring it back down again without permanent damage. The only issue is whether or not the subsequent track has plugins on it. If the clipped signal feeds an aux track, the plugins will be getting a clipped signal, and pulling down the aux track fader will do nothing for it. Master fader tracks have post-fader processing. The plugins come after the fader, not before like every other track. This means that if the input level is into clipping, you can use the master fader to pull it down before hitting the plugins.

The weakness is in the TDM architecture. Sure, the mixer moves and mixes audio at 48 bit, but handing the audio to and from plugins is done at 24 bit.

[JFreak]

Originally Posted by Top Jimmy

The weakness is in the TDM architecture. Sure, the mixer moves and mixes audio at 48 bit, but handing the audio to and from plugins is done at 24 bit.

Sure, it would be a nice upgrade ("TDM III") to have it 48 bit all the way. Just the same, it'd be nice if "the next one" would handle as many tracks/plugs @96k than the current system does @48k.

That said, perhaps we'll have to wait for few years longer.

(I'd want the next system to have the power of current HD3 with only one "core" card. And the entry-level interface would be like 2*HD192 interface w/AD expansion. Naturally it would not cost more than current HD1 system and a HD96 interface... I know, dream on)

[O.G. Killa]

Originally Posted by JFreak

That said, perhaps we'll have to wait for few years longer.

I would guess it's about 1 and 1/2 to 2 years away... and with all the new technologies and DSP that have come out since HD Accel was introduced, I'm sure it will blow away anything available by a long show and leave 8 core processors in the dust.

One of the things I like about digi...they don't release something just to release it...they really make sure they have thought it through and come up with the best possible solution given the available tools. ADC for PTHD comes to mind...

[JFreak]

Yep. Fewer releases is often more performance in the long run. I like it! But it doesn't mean HD is today looking a bit old. Let it be closer to 1 year than two, and I will be proud to upgrade.

[DrFord]

Well I think my question was answered. What I really wanted to hear was that the "48 bit mixing" is not just for the master bus, but is an instance on every bus/input that sums.

So it really in the end does come down to functionality of the method of bounce and should have nothing to do with sound quality. That makes me happy.

D