Author Archive: bruno

CmosOrchestra micro-live!

I finally managed to put together a 6 minutes track using all the gear I built:the BH-101, 3 LoFi Samplers, the 808-Kick Clone, the 808-Hats Clone, my Clap Machin, HP and LP filters, the Small Stone Clone and a couple of PT2399 Delays. Here it is:


It’s been a long time since I wanted to add a DIY sampler to my rack as the simplest way to get chords synth stabs to my music.After a bit of looking around I found this cool video about using an ISD-1820 as a cheap LoFi sampler: So I ordered a couple of these ISD1820 boards and followed the…
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I really wanted to have this project done, so I could enjoy myself a nice rotary mixer at home. The goal was to add one HP Filter on each channel and have the PCBs mounted on something instead of hanging by their wires.. I found the easiest was 5mm plywood so here it goes: I still need to attach the…
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BBMIXER: a DIY Rotary Mixer

I finally got my DIY Rotary Mixer working, and I’m quite happy with it! It has 2 lines, a PFL, individual and Master gain, and a High-Pass filter for some isolator-like action.I also found some inexpensive backlit retro style analog Vu-Meters.All impedances are dealt with using TL072 op-amps. Here it is in action: My next step is adding one HP…
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DIY Eurorack Cabinet

I had this small shelf I wanted to turn into a rack for a while: I had to figure out a way to hold the faceplates in the middle. A few pieces of wood used for baseboards will do the trick. I first have to find the right order for the few modules I’ve done so far..From left to right,…
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CMOS Orchestra Live!

A little demo featuring:– The BH-101 synth– The 808 Kick & Hats Clones– The B-Clap– The B-HPF and B-LPF filters– The Super-Simple 8 Step Sequencer– A very messy Delay!

Small Stone Clone mod part2: Univibing

The first mod will be getting this “Univibe” hack: The idea is to emulate the “Univibe” effect using the four CA3080 OTAs on the clone, getting both flavors.As explained in the link I must add another set of caps plus a switch per 3080.Fortunately my breadboard build had just the physical space need to throw 4 caps and four…
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Electro-Harmonix Small Stone Clone rework

It’s been a while since I wanted to rework my Small Stone clone aka the Piedrita by Tonepad. This is still on a breadboard but it works well and it’ll be easy to start messing with those 6.8nF caps when there’s no solder involved. Right now here is how it looks and sounds like:

BR-808 Hi-Hats euroracked

Following my goal of standardizing the stuff I built previously to be compatible to the Eurorack standard, I had this 808 Hats clone redone: Here is a little demo:

Eurorack Bus & PSU

I need to build something to power the new stuff, at least the BH-101, its waveform mixer and the Midi2CV interface. According to the Doepfer Eurorack specs, the pinouts go like this:I’m gonna go for the full 16 pin version, as I might need the +5V bus sometimes. I thought of something like this, which is gonna use my DP832…
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BH-101: Euroracked

To easily integrate the BH-101 amongst other instruments, I had to choose between the standards available. I went for Eurorack aka the Doepfer A-100 system. A bus with +12V, -12V and +5V is really the core of it, along with physical dimensions to fit in the racks. Eurorack requires a faceplate of 128,5mm x a multiple of 40mm, drilled with…
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Midi2CV-Connecting worlds!

I was not sure this would be a very interesting build as it is not a sound generator per se, but it still will gonna save me the 150E it costs to get a nice commercial Midi 2 CV interface. This looked like the best DIY project I’ve found, it comes complete with the arduino code and all: It…
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BH-101 Synthetiser

This is my first “real” voltage-controlled synth build using the CEM3340 clone the AS3340: The CEM3340 was the oscillator used in the famous Roland SH-101 and MKS-80. It has 3 waveforms: Ramp, Triangle, and variable-width Pulse. In my build I added a white noise generator, the Noise1B from ED: I’m mixing the 4 outputs with a GrandMixer DIY,…
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BB BP-1 Filter

Next on the list is building great filters, both resonating High and Low Pass, voltage control is a must if I want this to integrate further on a CV controlled system. I found this great component manufactured by Alfa and distributed by Electric Druid: the AS3320, a clone of the CEM3320 as featured in the Sequential Pro-One and the Oberheim…
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I just put together all the units I’ve been building. I just sticked the SSS sequencer, the PT39 delay, the 3080 Phaser, the Grand-Mixer, the 808 Kick Clone and the Nano-B synths onto a piece of plywood. Here is how it sounds through my iPhones mic and Youtube audio encoding.

808 Hi-Hats Clone on stripboard

After the successful cloning of the 808 Kick, I needed at least a hi-hat to go along. I found this great thread on electro-music, about building the 808 hats on a stripboard: Check the thread out here : So I decided to step up my game a little bit, and turned the soldering iron on.. After a first attempt,…
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Grand Mixer DIY

Now I need to put all thiese “modules” together, so I’m going to build the simpler mixer I can think of… That design is exactly what I think I need:

808 Kick Clone

Nothing better than the 808 kick as a first beatbox build, a solid foundation… There are many designs around based on the original service manual published by Roland, including all the schematics. I got help from this one, as the original schematics have been redone at a larger scale: Just be aware that you are going to need…
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SSS-Super Simple Sequencer

The Hackadays series by Elliot Williams are a gold mine: Logic Noise: Sequencing in Silicon This is a super simple 8 steps sequencer based on the Baby 10  featuring two 4017 ICs. Here is my breadboard rendition of it gating the power of a 4069/40106 based oscillator:

CA3080 4 Stages Phaser

I just love Electro-Harmonix phasers such as the Small Stone or the Electric Mistress.. I found these schematics to build a Small Stone replica using the CA3080 Operational Transconductance Amplifiers: The build on a breadboard looks like this: And the sound is great, here’s a demo using a great song by Adrian Nation, Five Fingers Rapid:  

Delays lays lays

My my first effect build I wanted to do a delay so I went and shopped around for designs. I found some cool ones there, based on the cheap PT2399: And here’s the PT2399 specs sheet: I build two different designs from very simple to a bit more sophisticated. The first has only a time control and…
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The OP-HPF High Pass Filter

I wanted to have an Isolator-style high pass filter device to play with. I found this design at that uses a very common op-amp, the TL072. And there I found the design for a 555-driven negative voltage generator, needed for the TL072: The only case I got is that Walkers biscuits box. Well English. I punched two holes to mount a rotary…
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The NZO-Control footswitch midi controller

My good friend and great guitarist Nzo needed a simple and heavy-duty footswitch midi controller… This Hammond case I found on Ebay was a perfect fit for this project. I took to the Arduino to manage the Midi part. I found these great Single-pole Single-throw switches on Ebay as well. Just a led and a resistor, VCC/Gnd and signal wires on…
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Nano-B the 2.50 Euros synth!

This is loosely based on the excellent series by Elliot Williams from ( . This is an awesome source to get into audio hacking. Here’s the BOM and price list: Breadboard             1.00E 40106 IC                 0.30E Switch                  …
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The Notes & Volts Audiuno Granular Synth

I’ve been interested in electronic music for a while, so I thought I’d just try to build my own synths. I found this great website and its Arduino-based synth “Auduino”… Let’s get to it..Soldering stuff, resistors, wires, breadboard, pots, Arduino and more. First I built an Arduino on a breadboard using an ATMega 328 (tut on the Notes and Volts…
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