Summing Mixer (I opened up the 2bus lt)

Ok what do the guru's here feel about Summing mixers?

I opened up this 2bus lt and just found 16 channel with a few THAT chips going through some resistors, capacitors & relays all connected together.  When I priced it out it was about $300 worth of parts.

Yay or Nay on summing mixers?  I've noticed we don't have a DIY summing mixer around here and it's such a simple design.

Thanks folks

There's quite a few summing mixers here. Stereotype, jeff's aca, gustav's majestic/buzz, etc. You could probably use some of the line amp designs (neve, helios) for summing as well.

I personally don't have experience with summing mixers in a digital setup so I can't comment on the sound.. But I'm willing to bet jeff's aca/booster board sounds damn good

Do you have any pictures you can post?

Could you trace out the circuit and post a schematic?

Thanks

Ill take several tonight and report back

first off

summing mixer

Click to expand...

drives me nuts. It is redundant, it's like saying my mixing mixer. Summing and mixing are the same thing.  Anyway there are plenty of DIY summing boxes as well as commercially available ones.  I think you will find that some people swear by them and others don't I personally have listened back and forth between some summing boxes vs a daw and all I can say is this, if it works for you, great. If you feel it enhances your music, great.  I think there is something to going out the daw into a summing and coming back in, maybe it's the extra noise and such  of being in the analog world and then doing another A/D conversion?  Who knows. The bottom line is  if it works for you then cool use it.

As for the cost of your summing box, yes it might only be 300 dollars in parts but there is more going on then just parts. For starters the circuit board it's on can cost a lot of money to manufacture. Then you also have the soldering houses who solder the parts on the board, yeah probably done by machine but that is still taking time and money to make happen. Then  you have to consider the metal work involved, engraving or silk screening, assembly of all the different pieces and testing all being done by some worker who is earning a paycheck of some sorts. Before all that, it's money for doing some RND to make the circuit. Considering it's a new design, they are probably making very little profit per unit to breaking even until money is recouped for all the time spent doing RND.  In the end for a while they make very little profit.

Now where it gets criminal is when companies reissue units/designs and still charge a huge amount for something that already made up money for all the time it took to create such a circuit.  There is no reason reissue gear should even be close to what some companies charge for it.

I don't agree fully here - there is a valid category for summing mixer - for my understanding the line mix consoles with faders are just that. I am thinking of the SPL neo and the Neve 8816 summer with the additional fader pack or my project. they are grown up mixing consoles but build to the sole purpose of summing stems and channels to an 2 track mix. so a summing mixer would be a very limited subset of a traditional studio or broadcast mixer.

just came back from Frankfurt and had a little hands on with the SPL neo. nice feel and touch, but the 19" limitation and the omission of any workstation control makes it unfinished in my opinion. 

of course here the term has probably been used in redundant fashion....

- michael

pucho812, what's your personal experience with mixing mixers (;D) and which ones did you try?
If I understood well, it doesn't quite do the trick for you?

A lot of engineers are stuck on the old studio look, thus mixing console...chuck that shit out the window. A good summing box kicks ass, followed by mixing in the box and last the dinosaur board. The problem is a lot of summing boxes are total stupidity from a design stand point. A quality circuit isn't about lights and switches, which must be built into the product to satisfy the consumers visual needs.

I did the 'chuck out the console' exercise a few months back and found the experience to be very liberating

My opinion is that the desk, good as it was in basic sound 'satisfyiness' was less 'vibrant' than either of ITB or summing bus.

At my stage in audio life, I didn't need the facilities of a desk any longer and the 'unburdening' pysch effect of removal was more significant than the sound improvement.

Between ITB and summing bus, not so much. The ITB does sound quite good. This is the first time I've done ITB/stem as my main mix and quite surprised at how much more satisfying the sound is over my previous methods.

I don't get much 'color' from my nevey style unit, just more 'aliveness' is the best way I can put it.

Not very 'sciencey' for sure, but as we all know 'science is bunk' 

Anyone want a free console? Chances of selling are not quite but close to nil.

that should probably go into the brewery, but still -

on a technical side regarding the sound of a mix I have no set opinion, but when it comes to the ergonomics of actually doing a mix I believe that the recent trend to ITB mixing and visual feedback (think plugins with full graphic support) are a real loss. One of the worst design decisions is to include 0.01 dB precision on digital controls and 0.1Hz resolution. quite some digital products have really mind blowing failures built in the HUI side of things. or engineers that visually tweak eq's until the curve looks right.

I looked at the new digital consoles in Frankfurt and I was as disappointed as never before. look at the new WINDOWS look all over the place with mixing consoles starting lenghty dialog sessions with you when all you want is do a simple operation. aaarrrggghhhh. or lag in the operation. ever had to wait until the mouse is really on the switch you want to press on an analog console?

sure total recall can be a real game saver, that I agree and the automation is is of course nothing to brag home about in analog consoles, if it works at all. all the capabilities of even a free recording software in comparison to a tape multitrack makes you wonder how they did it in the past.

so when it comes to summing mixer, consoles and ITB my list looks a little different.... well every ones personal taste I guess. It's just I realized I would never have started a career in this field if I would have had to use a (recent) digital desk in the old times, never ever... probably a dinosaur myself...

rooaarr!
and now back to eating leaves and trees....

I'm not a guru and I have no summing box up to now. But I think about it to build one someday. A summing box could be the best way to integrate outboard in the DAW based mixing-process. I have some nice preamps, analog eq's and compressors - and I want to build some compressors next years   I want to use this outboard to color some signals or for parallel compression or to mix into an analog compressor/eq. Maybe to have more headroom. But I have not the money/place to use a 24 channel SSL or Neve. I reed and study some circuits currently. There are active OP-Amp based designs like the 2bus with less distortion and channel crosstalk. More sounding like SSL some say. Otherwise there are very simple passive (resistor-based-) designs with more crosstalk and noise but maybe more open sounding? If you're a pro in mixing, you will make a good mix ITB too. Analog summing will not make a bad mix good and good ITB-Mixes are sounding not bad. There are some reasons to do the mix analog and there are some reasons against. Make your choise.

I sold my little Behringer 16/4 Mixer ten years ago because all around sayed to me: "Mix in the box, plug nothing between your sound card and your monitor boxes." I had a bad feeling to sell this little noisy mixer because I had the feeling my mixes was sounding better a little bit with this mixer. This is what I remember but this is subjective - maybe you love a little bit cleaner, "digital" sounding mixes, than ITB is the right way for you.

I would build a summing box with 24 Channels, Pan, +/-10db Gain (Class A?) - not less, not more. Sends/Returns are not so important for me, I would split the signals in the DAW.

I use this great forum to build some outboard for myself. So I'm interested how the 2bus is construct. Do you have photos?  I think there are only some OP-Amps for Pan and Output inside, some caps and resistors around. The bigger 2bus have some OP-Amps more for 6db Gain- isn't it?