lo-fi vintage mixer diy

[stojadin653]

Finally i completed this diy mixer ,it's not as pretty as some other things i've done ,but i changed my mind too many times about too many things while building this ,so in the end i only waned to complete it and it's done . This is a Buchla 106 Mixer ,with 3 x SIAM (Siemens based EQ) on 3 channels on one of the two groups of the 106 Mixer .There is passive mute on all channels and 4 groups of aux channels based on early Serge Mixer using 741 ,i expanded the 106 to 4 channels for group or 8 in total ,so that extra channel at group is actually two channel summer meant to be used as return for 2 aux groups ,that sums it up to 6 Serge mixers. The 2 extra channels have Tape Saturator Colour MK1 which can be bypassed with high pass switchable from 40hz to 60hz .The second group of the mixer has no equalizer . In addition there is 4 channel input joystick that works as a four channel panner ,or two x two channel panners ,it can be useful to browse thru the 4 aux groups ,the joystick has Colorupter Optical Disrupter Colour that can be bypassed .This build was not easy cause i reused lot of materials for the panels and the enclosure ,the enclosure is leftover from machines in an old textile factory ,the inputs and outputs are in the back of the enclosure and that part is fitted additionally but it turned out beautiful. It can not be compared to most stuff people build on this forum ,in the end i didn't bother with the looks i just wanted to complete it cause in the beginning this was way bigger project and it was different enclosure much more electronics for which i even printed a panel and made the wooden enclosure ,anyway i am still happy with this ,it is just for fun and it won't be something tempting to sell it .I wanna use this for feedback and noise music .Large part of the mixer is made on stripboard .Now waiting on the knobs for the aux pots as these need to be small to fit nicely ,later i want to take better pics if that's possible .

https://blogger.googleusercontent.c...tDedYtI5bHm3aD_ldysBQ2u9Tg/s3192/mixerxxx.png

 

[KrIVIUM2323]

I like the whole thing: concept, built and planed use! Congrats.
Buchla and Serge marriage can only sound interesting as outcome.

 

[stojadin653]

Thanks ,it took me a while for no reason , i even made two layouts for active mute https://synthesizerunderconstruction.blogspot.com/2024/08/mute.html and even one of it i made PCB but there really was no need ,at least for me , while looking at Soundcraft mixer design i found passive mute ..but i often joke that this is a mixer from the future cause as i believe the Chinese are about to make a push button switch that i will like to add as mute switch ,could not wait

 

[fragletrollet]

Very cool!

I've been interested in making a more studio friendly version of the serge resonant eq I have in my modular. Stereo, maybe API doa active inputs and outputs with trafos on the outputs.

The serge eq is something special; I wonder if it is merely down to the frequency points and spacing, which are supposed to mimic points emphasized in acoustic instruments (pretty vague and loosely defined imo). I built mine with fancy polystyrene caps and cheap general purpose ic's. It sounds wonderful, and is a great sound shaping tool.


I've also heard that there are some pretty colorful mixers by serge, too. Randomsource sells them built, but their prices are too much for me. Would be cool to build one, I guess schematics are around.

I built a 296 filter bank buchla clone (just the filters, no interpolating scanner) but while cool, it doesn't share the euphonic qualities of my reseq. It was smd, so was built with cheap caps from an assortment book. Same cheap opamps. Wonder if it is the design or part selection that makes for this different quality.

 

[stojadin653]

I had a Serge Resonant EQ and so many people love it ,i didn't ,don't know why ..guess it's just taste .Both type of mixers i used in this project are the simplest ones ,the Serge Mixer is just his first old mixer just a 741 opamp ,and you know 106 Buchla is 6 transistors .as for filter banks i was obsessed at a time with Bernie Hutchins filter bank from Electronotes with 39 Bands ,made layouts for it but have not built it . Now i wanna try a filter bank from Osamu Hoshuyama and made PCB for it ,i intended to make it 24Bands but it seems i'll just make 12 Bands since that it how my panel turned out .Sometimes i think i should have just bought some mixer instead of going thru all this trouble but can't quit building stuff ,all the machines i bought at a time ..not so many ,i sold ,i can really play mostly my diy gear .Now i have a homemade modular ,mixer and 6 pedals ..now just building pedals is most fun .

I built 6 of these ,4 to use as aux groups with 3 channels each ,and 2 as just 2 input summers for return channels



on the image ,my synthesizer (mostly Electronotes) ,the mixer ,and one of the pedals (Tone God Christine Fuzz)

 

[fragletrollet]

My modular
I'd say about 50-60% self built. Notice ResEq (w/Faders) and 296 on the right of it (Blac with red/cream fadercaps), both in bottom left case.

View attachment c2bfeb04-3fa8-4277-b103-9e64bd6ea2a5-1_all_31.jpg


I'd recommend the L-1 modules too, their mixers are Cwejman copies/inspired and are insanely clean and high headroom. Not a bad starting design for a studio mixer of modern style. Haven't found any schematics for them though, but presume it's just expensive opamps in standard configs, nice PCB layout and clean power management.

Another mixer I absolutely adore, is the Moog 984 4x4 matrix mixer with 2band eq on each output. Built it with fancy "audio" electrolytics and big wima film caps. All discrete transistors and no ic's. Now that is a colorful mixer, and the eq is great. Would also be a fun idea for a 500-series channel, as the output could need a beefier driver if going direct to other gear without something like a 1646. But we'd keep it discrete, so maybe something like the typical API doa / 2623 combo...


Food for thought

 

[stojadin653]

Nice Studio ,lot of gear there ,congrats .I made my gear with very small budget ,and i've been building synthesizers for over 10yrs ,sold some ,not so proud about some pieces ,some turned out interesting . Here you can see most of what i've built https://synthacks.blogspot.com/2016/07/blog-post.html

This is all built from scratch ,ordering parts ,making pcb layouts and so on. I like how the last one turned out ,it is single panel 4U ,on +-15V
That one went in Croatia ,i kept the other box from the picture ,to be honest i don't need much gear if i feel like playing i have enough to make it interesting enough ,still there is few modules i like to complete simply cause i spent time making the layouts ,hours on the internet to compare versions of it and so on .