VCAs and busses and masters oh my!

[David MacNeill]

I'm scratching my head trying to tame and master a pile of mixes in which nearly all the tracks are recorded at or near digital 0, and occasionally go 2 or 3dB over. I tame these (usually the stereo drum track) with Kazrog's K-Clip but dare not clip vocals and clean guitars and synth pads and pianos. I can't figure out if I want to do the VCA thing for instruments, drums, and vocals separately, then drop them down before mastering. My question is, where do VCAs route? Straight to the 2-buss or to Logic's Master Volume? Should I use regular aux busses instead? At least I know that they all feed the 2-buss. What the hell is Logic's Master Volume anyway?

I use Masterdesk True Peak as my mastering compressor/limiter/equalizer/stereo enhancer/saturator. It works quite well, sounds musical, and most importantly I understand it. But I've found that if the tracks coming into the 2-buss are too collectively hot, Masterdesk's limiter just gives up and lets the whole mix exceed the -0.2dB limit I set and the track gets all woolly.

Am I thinking about this all wrong? Help me, Obi-Nahmani!

Below is a screenshot of a typical mastering session:

Edited February 4, 2023 by David MacNeill

[des99]

First, don't worry, you can't clip tracks - it doesn't matter if you go over 0dBFS as such at the track or bus/aux level, nothing bad will happen, as long as your main master out is under control and well below 0dBFS (or at least, not clipping).

Note - tracks can't be *recorded* at "2 or 3dB over", they will either clip at zero, or not.

You may want to add a gain plugin, set it to, say -10dB, "Save as default" to make this setting be the default when you load the gain plugin, the select all your tracks, and add a gain plugin as the first insert to all of them in one operation. Now all your tracks are reduced by 10dB and should be globally easier to work with.

3 hours ago, David MacNeill said:

What the hell is Logic's Master Volume anyway?

It's just a single remote control for all of your interface outputs at once, mostly intended for Surround work. Ignore it, it's kinda useless for stereo work and can often cause level problems.

(Sorry, you just got Obi-Des instead - apologies for any disappointment caused! 😉 )

Edited February 4, 2023 by des99

[polanoid]

48 minutes ago, David MacNeill said:

where do VCAs route

VCAs don't "route". You can think of the VCA fader value simply as a dB value that is added to the volume fader value of every channel strip it's assigned to. The VCAs don't route any signals anywhere.

So, Logic's Master Volume is basically a VCA that is (unchangeably) assigned to all Output Channels.

Edited February 4, 2023 by polanoid

[David MacNeill]

1 hour ago, polanoid said:

VCAs don't "route". You can think of the VCA fader value simply as a dB value that is added to the volume fader value of every channel strip it's assigned to. The VCAs don't route any signals anywhere.

That would explain why my experiments with segmenting sections using VCAs plays havoc with my effects busses! I even tried running all effects busses to their own VCA but it wasn't the same as before I used any VCAs — I worked really hard getting those effects just right.

[David MacNeill]

So VCAs are out as a solution to this particular gain issue and Logic's Master is out too. A Gain plug at the top of every track at minus 10dB sounds like a winner, though how this affects my effects busses remains to be seen — probably should drop them all down 10dB too?

[des99]

1 hour ago, David MacNeill said:

So VCAs are out as a solution to this particular gain issue and Logic's Master is out too. A Gain plug at the top of every track at minus 10dB sounds like a winner, though how this affects my effects busses remains to be seen — probably should drop them all down 10dB too?

Good thought* experiments to better help you understand mixer routing:-

Where is the send point from a track (which will be sent to your FX busses). Is this before, or after the plugins? (Ie, if I use a gain plug to drop the channel level down, will it also drop the level of the sends by a corresponding amount, or will the send level be the same?)

How do the various options to change that send tap point (eg, pre/post fader) affect this? If the send levels are the same, do I need to also reduce the FX buss levels? If the send levels drop by 10dB, do I need to adjust my FX buss levels?

* If you're not sure - *test*... 😉 then you'll know how it works, and can better make these decisions in future projects. 👍

Edited February 4, 2023 by des99

[JakobP]

Why not put a gain plug-in just before your mastering plug-in ? Or simply lower the master gain in the EQ before it ?

Edited February 5, 2023 by JakobP

[David MacNeill]

18 hours ago, JakobP said:

Why not put a gain plug-in just before your mastering plug-in ? Or simply lower the master gain in the EQ before it ?

I'll try it! As the general said in War Games, "I'd piss on a spark plug if I thought it would help."