Popslut's scientific "analogue summing vs. ITB test.

[forge]

Every time the subject comes up, my hind-brain screams "Buuulllshiiittttt!11".
Fortunately for me - my signal chain and room is so crappy that theres no chance of needing placebo acoustics any time soon.

+1 - was going to say the same - the only monitors I have ar NS-10s driven by a shitty old amp so the mere concept of this kind of test is well out of my reality at present, but it's interestng nonetheless - but I do at least have tissue paper over the tweeters!

the whole debate of sound quality these days just seems like a total fucking waste of time

same as computer power - my mate is out to buy a new iMac and he was getting all uppity over whether he want's a TB of HD space and 2.8GHz core 2 duo or just get the 2.4 and I was saying to him that I seriously cannot think of a single conceivable thing that he might want to do with it that will require that much processor power and he already has several very big external hard drives

Agreed on the sound quality point. A complete waste of time to worry about these days. Although I disagree about the processing power. I am fine for hard drive space now that I have a 320 GB internal on my MBP, but my 2.16 C2D is still not quite enough for me to feel like I can throw anything on any track that I want. I like to keep things non-bounced and I like processor hungry instruments and effects. Once a quad comes out, I'll be very comfy.

And also agreed on the hardware mixing vs In-the-box. The only thing I'm willing to admit hardware will provide over software is analog overdrive. I only know this from being a guitar player. When analog gear is driven to overdrive it can give a sound more pleasing to many than software counterparts. But that difference is narrowing too. I can imagine that some desks out there are praised for that overdrive characteristic, but I'm still more than happy to throw my favorite saturation/overdrive plugs on a track for that .

Nice test btw, thanks. Now would you mind testing Live 7's 64 bit marketing...er. summing against Live 7's measly 32 bit quality?

I was really meaning for my mate in particular who is a total luddite DJ who just wants to use it to chuck a few breakbeats and a fat bassline together

[Sales Dude McBoob]

I think it needs to be said that pro audio gear categories tend to exist for a reason. Just because popslut and his home mixing console couldn't justify why anyone would need a quality analog summing bus doesn't mean that they're useless to the entire population.

If you brand this equipment with the foofy "audiophile" stamp, tell me, what other pro audio gear falls into this category?

[leisuremuffin]

i'd be willing to wager that popslut's home setup is pretty high end. Well, if all the stuff he says about himself is true.


at anyrate, doesn't it occur to you that it could infact be a bunch of snake oil? I sure think it is. But I've also been in a room full of pro engineers doing a mic pre blind test and laughed my ass off as they couldn't differentiate shit from shinola.



.lm.

[Tarekith]

Cue my favorite Roger Nichols article:

"I heard the mixing buss in Pro Tools is no good. Everyone says I should mix through an external analogue summing buss."

Someone asked Al Schmitt how he mixed a record. Al answered "I just turn the knobs until it sounds good." You can't argue with that.

The first thing I had to learn about audio engineering was signal flow. You have to know how to get the audio signal from the microphone to the recorder and back to the speakers so you can hear what you are doing. The second item is gain structure. At any point in the signal path you have to keep the signal higher than the noise floor but lower than the point of clipping and distortion. Everything else is going to be easy. Just twist the knobs.

Every console is designed to add signals together before they come out as finished mix. It is called a mix because the individual tracks are mixed together. I rather fancy the English term 'two-track reduction': it is being reduced from 24 tracks to two tracks.

Physical consoles usually have a stereo mix buss 'summing amp' for each group of eight modules. These summing amps then feed another summing amp connected to the master output module. During the mixing process the master fader is turned all the way up. As individual tracks are turned up their audio is heard through the master fader and the level is registered on the main output meters. As more and more audio channels are introduced to the mix, the overall master level starts getting high, so the master fader is turned down a little to compensate. This work flow proceeds in a loop until the mix is getting pretty far along.

At some point the engineer looks at the gain structure of the mix he has going on the console. He has learned that by running the individual faders high and pulling down the master fader he runs the risk of overdriving the summing amps with too much level and adding distortion to the final mix. The engineer will trim down all of the track faders by 6dB or some similar amount so that the master fader can be brought back up to zero.

This method has worked for decades to keep the audio quality as high as possible while remaining within the limits of the console's design, but for some reason engineers ignore this procedure when mixing inside a DAW (digital audio workstation). When asked why they don't perform this requisite task the answer is always "It's digital, you don't have to do that." All of the 78 track faders are up near zero and the master fader by now is down to -40dB. Soon the engineer starts to complain about how gritty and distorted digital sounds.

How do they fix it? They connect the DAW to a console. At the console they either trim down the inputs or pull down the track faders to prevent the summing amps from clipping, and they make sure that the master fader is all the way up. "Hear how much better the mix sounds through a console?"

Sound familiar? I know all of you have run across this situation from one end or the other. The smart guys who saw this wanton disregard for gain structure quickly designed 'outboard analogue summing boxes', charged a lot of money (because it can't be good if it doesn't cost enough), and made a fortune. Good for them. Too bad I didn't think of it.

Because Pro Tools was the most visible professional DAW, Digidesign took the brunt of the criticism. "Man, I can't mix inside Pro Tools, their internal mixer sucks." Although there were tons of good-sounding records made and mixed in Pro Tools by engineers who knew how to turn down a fader, the majority of the forums on the Web hosted tons of complaints. "It shouldn't do that, it's digital."

Digidesign have updated their internal mixer to 48-bit. This means that you can mix 128 faders at +12dB with the master fader down to -90dB without overdriving the internal mixing buss. There will not be much room for a final fade, but at least Pro Tools is now being idiot-proofed. Me, I prefer to watch what I am doing and trim all of my faders down so that my master fader stays at zero. It has worked for me since the '60s and continues to work for me in whatever digital DAW I mix in.

PS: Just so you know, I do tell my clients that "I only mix on dual 64-bit processors with a 48-bit mixer fed by 16 gigabytes of memory and an on-line RAID5 disk array of 8 terabytes and a 15 gigabit-per-second fibre-optic Internet connection. You do hear the difference, don't you?"

[morerecords]

I would have to disagree, sort of-
"summing mixers" ARE a scam, when the industry needed to push out a new product everyone "needed" it's hype.

that being said, here's what I learned, and what I practice:
NEVER summ stereo tracks through a console, that's foolish because we all know how hard we work on a nice stereo image and running stereo tracks through a console, your imaging greatly suffers as opposed to "ITB"

But, an analog console is one of the best ways to get your various mono drum groupings tracks to "gel" and utilizing a good outboard EQ and distorting real mixer channels a little works wonders for techno. Even if you were to do nothing but simply "summing" you will get the sonic "personality" of the board.
as far as "summing" it's not as important to the desired effect people think they are getting from summing as just including this stage at some point of their mixdown, not "summing" but simply using a console as a processor

By utilizing dual cards and two computers(or one super-computer that could handle), you can track from one computer, through your console, to another. You can pay to use a studio with a high end console, it doesn't cost much, but this year I have been very happy using an old mackie and two computers, tracking Live to Logic via my Mackie with 16 mono channels, in and direct out. No "summing" the summing issue is just hype, but running your mono channels through your console, well, that CAN'T BE BEAT.

[knotkranky]

I think it needs to be said that pro audio gear categories tend to exist for a reason. Just because popslut and his home mixing console couldn't justify why anyone would need a quality analog summing bus doesn't mean that they're useless to the entire population.

If you brand this equipment with the foofy "audiophile" stamp, tell me, what other pro audio gear falls into this category?

It's a matter of history and change.

Digital summing used to suck and bussing out individual stereo pairs was helpful.

Then, digital summing was well improved overnight. "blink"

Then the hurting analog hardware folks making summing boxes didn't have much after that, except aggressive (can't you hear it?) voodoo marketing.

Besides, we're not talking about analog "gear" we're talking about analog mixing consoles and their little tiny cousin, the mix summing box, which nobody needs.


McBoob, it's important to know your history. Protools HD sounds fucking amazing, your earlier uninformed or maybe disingenuous comment was for old PT "mix systems" from about 8 years ago. Back then summing PT mix3 systems (which I owned then) sounded best summed into a console. But, not anymore. This is par for the course for PT being innovators.

Analog mixing is old, old, old. Even the old classic record golden ear engineers, of which i;m still friends are mixing in protools HD in their living rooms.

Thanks to popslut for going through that boredom, lol. Right, forget those dumb ass summing thingys. But, by all means, buy great analog gear, but only for input stuff. Once it's ITB, stay there.

[nebulae]

With this kind of helpful posts, I can't keep calling you a slut anymore.

I will say though, that tests like these prove to me what I've suspected for years...that mixing in the box isn't noticeably different than mixing out of the box. What's next?? That Macs don't produce music any better than PCs? Heaven forbid the blasphemy!

[popslut]

Analog mixing is old, old, old. Even the old classic record golden ear engineers, of which i;m still friends are mixing in protools HD in their living rooms.

That's all very well, but I'm three hours into mixing the same track on my analogue mixer and it sounds much better already.

I'm not making any claims for why that should be: familiarity is just as likely a reason as anything else.

I'm not even saying all summing boxes are snake-oil.

I did my experiment and posted my results along with my opinion at the time. I know what I think - your kilometers maybe different or whatever that fucking saying is.

It's gratifying to read some proper Ableton Forum nonsense though.

NEVER summ stereo tracks through a console, that's foolish because we all know how hard we work on a nice stereo image and running stereo tracks through a console, your imaging greatly suffers as opposed to "ITB"

What an absolute gem.

[Moody]

Anxiously waiting for Pt.2 results.

[nebulae]

Cue my favorite Roger Nichols article:

And yet with all of that wisdom, he still overprices his plugs!

[popslut]

I will say though, that tests like these prove to me what I've suspected for years...that mixing in the box isn't noticeably different than mixing out of the box.

Fail.

I didn't mix it OTB - I just summed it.

Now I've split the outputs, switched in the eq and got busy with some proper inserts and fx and suddenly the ITB version sounds like a demo.

[nebulae]

That's all very well, but I'm three hours into mixing the same track on my analogue mixer and it sounds much better already.

Ok, thank god you posted this, so I can go back to saying,

"You SLUT!"

[Tarekith]

Cue my favorite Roger Nichols article:

And yet with all of that wisdom, he still overprices his plugs!

Amen to that.


Would be interesting to post audio examples of your tests too, I'd love to hear them myself. Even just short 10 second samples.

[Mesmer]

I've been wondering about these analogue summing boxes you can buy and whether they actually do anything useful or not.

I've done my research and I've discovered that a lot of far more experienced engineers than me think they significantly improve the sound of ITB mixes. Trouble is, a lot of other far more experienced engineers than me think they're bullshit.

So, no answers there.

The only solution is to hear it with my own ears so, this morning, in between sessions of frenzied masturbation and subsequent self-loathing, I decided to test the theory.

The Test.

I've just spent two days mixing a track for a client in Nuendo. I'm happy with it. The track is split into six stereo subgroups; drums, bass, guitars, synths, vocals and fx and then bounced down to a 44.1 khz / 32 bit float stereo wav.

I've sent each subgroup out to my desk - a Soundtracs Solo Logic 32 - via two RME Fireface 800s - to six stereo pairs made up of twelve identical mono input channels.

Care was taken to calibrate the input gain and fader positions to acheive unity gain. Zero dB at the output = zero dB at the main buss faders of the mixer. This was done with the RME Digicheck application applied to the DAW input channel and apparently accurate to 0.5dB.

The main buss of the mixer feeds a Focusrite Mixmaster Platinum which outputs wordclocked SPdif to the digi-in on the master Fireface, and thence back into the DAW.

I then printed the mix summed through the mix buss of the mixer and compared the two. The levels were very well matched.

I checked the results on Yamaha NS-10s with a Bryston 4b amp, KRK V8s, a 50 quid Pioneer boom box and a pair of AKG K-240 headphones, and just to be sure I was really hearing any difference I asked my wife to switch between channels from the next room using a qwerty keyboard with a long extension so I couldn't hear the key click.

Guess what?

The Result.


I couldn't even tell when whe'd swapped between the versions, let alone hear any difference. They might as well have been the same file.

Just to recap for anyone who missed that particular bombshell - no appreciable difference whatsoever.

Nothing.

Nada.

Not a sausage.

Bugger all.

Not "warmer" or "punchier" or "deeper" or "better stereo imaging" or any of that horseshit. Just the same fucking mix.




A few caveats:

1. I don't by any stretch consider myself to be Mr Golden Ears. I don't pretend I can hear a mouse fart from two rooms away.

2. My mixer wasn't designed by Rupert Neve or George Massenburg. It is, however, well maintained and sonically very adequate. I've done a lot of mixes on it over the last 15 years and I know it inside out.

I did phase invert the two files, just in case there had been a mistake and I was listening to two identical files, and they didn't completely cancel or phase. The residue was mainly top end - hat and snr transients - and could possibly have been due to a slight sample shift caused by the OTB mix passing through 30 feet of balanced cabling, a mixing desk and two stages of D/A - A/D.


Conclusion.

I admit I was expecting at least some difference. Fatter drums or better transient response or something. The only result I wasn't expecting was "no appreciable difference".

At this point, regarding analogue summing, I call "Bullshit".

Now I'm going to mix the track again on my analogue console with all my "vintage" outboard [don't get excited, it's all garbage. Interesting garbage, nonetheless...] and I'm almost certain it'll sound better than the ITB version by a huge margin.

I'll let you know.

... So, wait a second:
you're married?!
what has this world come to?!!! lol.

oh, and also, just to be clear, when in this thread we are talking about the uselessness of Outside the Box Summing Boxes; is this meant to be debunking the whole SSL Duende, it's famous SSL glue and other hardware like that?

thanks.

[Khazul]

That's all very well, but I'm three hours into mixing the same track on my analogue mixer and it sounds much better already.

Stuff I do allways sound better when I mix it on a real desk - I used to think it was because it was an analog desk, and for analog desk abuse then thats still true, you could plumb in some random bit of analog gear that gives the appropriate coloration when abused instead.

Eventually it finally dawned on me thats actually its just a desk with all the knobs there to tweak, positions of each clearly visible, levels clearly visible, patch bays clearly visible (so I can see whats routed through what fx etc). ie the damn could be a midi controller and a decent meter bridge.

So if I won the lottery, I would probably go out and bu a pro-tools rig tomorrow - not because I hold PT to be particularly special, but because you can get a absolutely amazing control surface (allbeit for several hundred K) for it thats beatifully integrated and with enough direct knobbage on it to keep even us analog knob whores happy

I still miss my old console, but I absolutely do not miss endless tracking sheets etc, or some arse fiddling, or worse clearing the desk down because they had to reedit a voice over in a hurry and used the first suite they could find and ignored the "in use" sign on the f***** door - grrrr!

I still use some analog gear now - because to date I still havnt found viable plugin alternatives that I like as much and that dont cost some rediculous amount of money. They probaly do exist somewhere - maybe I just havnt looked hard enough. But there is no doubt that while very quick and simple to patch in and tweak, its a pain in the arse to manage - tracking sheets, servicing etc and then add while working mostly ITB, it adds a load of latency etc which in turn takes away immediacy...