Summing Mixer - Do I need one? Which one?

Update from the OP: So I think for my next mix session this week, Im going to try printing the through my Vintech Dual 72s and Tonelux Equalux and see how much difference it makes... My thinking on using the Dual 72s is they are based on the Neve 1272, which was used for make up gain on the mix buss. I know the Vintech is a bit of a different thing. But it sounds fun to try

The other half of "everything matters," is "none of it matters." Too much emphasis on the first one, be reminded of the second one. And vice versa.

I think obsessive audio types often skew too far in the neurotic "detail oriented" direction, which can quickly result in psychosis of some sort. You can look at some of the thoughts people have been having here as an example.

I hesitate to discuss "summing" in general because once you've started to discuss it you're already far off in the weeds. The deeper you get, the more lost you are.

In my understanding, the light at the end of the tunnel is, "none of this really matters in any meaningful way." That can be your freedom.

Summing is dependent on the issue where all analog is subject to the laws of electromagnetic waveform physics, something that science is continually learning more and is really hard to understand. Transformers, inductors, etc exist because wire carrying signal also produces a magnetic field around the wire. That electricity is induced into conductors (copied over) within the field. The electromagnetic field of a signal on wire spreads like a magnet does but it’s invisible so it’s hard to understand the impact.

This is the thought experiment that got me:
- a 30Hz waveform at +22dB is going to have 30 positive and negative moments.
- a 15khz waveform that’s 40dB quieter is going to have 15,000 positive and negative moments.

If they are both going at the same time, then those +22dB peaks at 30 Hz will be a massive ocean of positive electrons during its peak.. and cause the 15kHz quieter, much smaller negative moments to change its sign from negative to positive. We know that if you put a negative charge in a bigger positive charge it will align with the surrounding bigger charge.

And so really summing ITB shouldn’t be the same, the math is exact. The effect that analog electromagnetic I’d sort of expect is to act to side chain de-ess and blend things into one during extreme peaks of low end.






Eric Valentine does have a video on a cheap DIY summer based off neve, sounds pretty nice as well

Workflow & ergonomics are completely intertwined. IMO impossible to separate.

With the option for both here sonics aren't much of a debate. We can stay ITB or go outboard through the little SSL sidecar. Both are cool. But my approach with each is completely different, and since they're made up of completely different tool kits then the resulting mixes? One isn't better then the other.

But... maybe the workflow for a given project makes one a better choice then the other? Deadlines & such can sometimes pull rank over chasing tone and "the cool factor" but that's life.

One of those methods stays inboard and doesn't use a single patch cable. The other takes 16 outputs and hits a 20 input desk with, very likely a couple dozen pieces of outboard hung of various points. Obviously different methods towards achieving the end result. 

Ultimately any similarities between an outboard & inboard mix boil down to the constants... and there's only a couple of those. One is the room. Monitors are the same and yeah, center section of the desk controls all those so that's the same too. And my converters are the same, only its 2 channels not 16. 

But the only other thing between those methods that's the same? Me. 

Very likely that any similarities are going to boil down to how I'm hearing things and my reactions. Elements like vocal placement against the drums... the kind of reverb/delays & general depth of field... how I hear that stuff doesn't change from ITB to outboard. I'm still me. Wherever I go there I am..? 

So while like everyone else I have preferences... for the crowd that's asking "If it makes a difference" - I'm not sure I'd go thinking about a summing box being a magic wand that "poof" is going to be an instant shot of horsepower. If you aren't happy with your mixes in general? Ehhhh... right. 

But if you might already have a collection of outboard, and want to use some of it while mixing... and it encourages a different way of thinking & working? And maybe that provides a superior, or at least radically different result? Now maybe 'ya got something. 

Things to consider.

Number of channels being summed is going to greatly impact the effect because of the makeup gain being asked from the summing amp.

Small differences between channels are going to introduce variance that’s hard to replicate. A few tenths of a db and so.

Pushing a summing amp hard is going to be similar to pushing a mic pre hard. If you do or don’t appreciate or hear the latter you will or wont the former.

Noise is increased with analog summing, right wrong or indifferent.

THD is increased with analog summing, right wrong or indifferent.

All true. At least from a quantum theory sotra level. In practice though? I dunno... some of the digital tools can have far more THD & noise then anything in the analog domain short of a RAT pedal. 

Thinking of things like tape & console emulations... various saturation plugs that resemble an effect more then anything else. Like if a tape machine or console was saturating that much in real life? We'd probably say it was broken. 

Plopping the 2 mix through a set of mic pres? Yeah I did the 1272 on the output of a smackie 8 buss thing a very long time ago... was an attempt to get some "tone" back into the picture. And if you like what that does its totally valid... but ultimately its an effect. Very obvious from the way it flat lines transients & crushes up when hit hard. 

That's kind of a different thing then running a real desk/box which, even when loaded down is quite a bit more linear. Unless you go for the intentional overload and run flat out, which most people won't do because it doesn't sound all that great. Not all the time anyway. 

Anyway... I find that typically at the intersection of practice & theory... noise floor? Between the inboard & outboard mixes... probably due to noise emulations in plugins there really isn't much of a difference. There's always hiss and other junk with either method. Digital is never 100% silent. 

Note : backing up what notneeson mentioned - the Silver Bullet is NOT a summing box.  For your application, it would GREATLY augment your mixing setup - with a Neve and/or API and/or SSL master buss inserted into your Soundcraft.  I've used the 2020, and it would significantly give you more options should you try one.  I used to use one all the time on my D&R's which were notoriously "transparent" when I wanted some classic color.  

Add reamping to the list. 

I would LOVE one - but can't afford $2700 right now...

I can hear a difference.  The difference "I" can hear, is the Airwindows mixes are way worse!  They neuter the punch of the kick and bass sounds, and basically add nothing postive in return.

To each your own.

And I'm going to continue to be a stickler for technical details.  The Airwindows plugins work "around" summing in the same way that Waves NLS, BX Console and others do with separate "channel" and "bus" plugs.  But these are really distortion tricks, and in fact are "NOT" summing!  They work around summing.  These plugins don't sum in any way.

Summing is basically a whole bunch of wires converging down to one or two wires.  With whatever passive or active electronics and/or algorithmic DSP is required to make this happen correctly.  The opposite of splitting or multing.  That's it.

It's not going to make you sound like Britney Spears and it's not going to get you a dinner date with Paul McCartney or Sting.