Everyone has been great, and this has been an amazing run, and a solid few years seeing everyone's projects and watching you all learn and create!

We have lots of overlap with our friends over at /r/synthdiy, and we've talked about this move a bunch and now it's official.

The old posts will remain visible for future reference material.

Thanks to everyone who contributed and everyone who showed up, and everyone for being easy going and making my job a breeze.

If you have, what VCO design did you use?

btw if anybody here is interested in the CHA/V here is the website

http://www.dewanatron.com/instruments.php?page=swarmatron

Has anyone ever cracked one open? Does anyone have the schematics for this?

I have a question regarding sound modules. I want to know if it is possible to buy sound module components minus the controls and casing, for use in a project? If this is not the place for this post please let me know and I will move it.

What should I get from Digi-key or other reputable source that can function as a VCO, with as much stuff built in as possible!

Hi, I want to make a pretty ambitious 4 voice analog groovebox. I'll have an arduino (with 5x4 button matrix) to control the steps, the things I'm not sure about is using the analog outputs from the arduino to trigger all the different oscillators (one noise, two square and one sawtooth), plus how to make a simple decay-only envelope and how to make a low-pass filter with a pot (no resonance control). Am I making it more complicated than I need to? Should I start even simplerer than I am at the moment?

My plan is to prototype the user interface and write the arduino sequencing code, using mozzi to simulate the analog components. And then once I've got that going and it turns out to be fun, implement each of the analog voices, voltage controlling them from the analog pins of the arduino.

The description I have so far is:

Four

Four voice analog synth

Voice 1 - Kick

Square oscillator with two pots, one for frequency, one for decay envelope. No snap.

Voice 2 - Snare

White noise oscillator with knob for decay envelope. No tom, not tunable.

Voice 3 - Bass

Voltage controlled square wave oscillator with pot for decay and pot for filtering.

Voice 4 - Lead

Voltage controlled sawtooth wave oscillator with pot for filtering. No ADSR.

Does this sound doable? Are any of those VCOs / envelopes crazy hard to make?

Hi /r/diysynth,

I'm currently working on a design for a multi oscillator drone based on this circuit from Look Mum No Computer and I have a question about how I would have the circuit switch to a CV signal when a jack is connected.

Here is my revision of the circuit so far. I have condensed it as there are going to be 16 of these oscillators and I need to save space. All I want is a component or something that will switch the signal from the linear pot to the one from the optoisolator only when the switched mono jack has something plugged in it. I guess it would sit in the box that has the question mark on it, but i'm not very experienced with building even mildly complex circuits so I may have missed something.

Thanks for reading!

Hi guys, I am working on an experimental input project and I have to go the hard way (no midi format) to generate the CV signal.

I looked at the schematics from MFOS and Korg MS, they have a chain of resistors with switches (at first glance it makes sense), so If you press a key you get R0+R1+R2...RX where X is the key you pressed and the voltage gets dropped at the note value.

The problem of this system -and here I don't get how to proceed- is that if I press 2 keys (which would happen on my device, and is useful anyways for legato arpeggios) the voltage is drifting from the upper note because I am having two resistors in parallel: 1/(R0+R1...RX) + 1/(RX...RY) this would be the new maths then.

I am not an engineer and don't understand much of the MFOS board but I need to build my own schematic for the project, and am here to look if someone can enlighten me on how this circuits are breaking this basic electronic rule. I was playing around with diodes which were doing the job perfectly, but as I put 24 of them in series the voltage drop grows to high to be able to control it. I am working right now on this simulator: http://lushprojects.com/circuitjs/circuitjs.html

my circuit is somehow simpler than the MFOS but I haven't also got the noisy keys issues he had (so no comparators or other fancy things, just the bare minimum and a some more work at tuning trimpots instead).

KEYS->S&H->PORTAMENTO->OCTAVE

I hope some long bearded synth wizard can answer me.

Greets

In this picture, I see that wires are to connect the PCB board to the jacks and power, meaning you could enclose a PCB board in a custom enclosure and just use the wires to get to wherever you drill holes.

However, in this picture, I see that the pots are attached to the PCB board in such a way that is "right against the board", thus preventing me from getting creative with space in a custom enclosure.

My question is, am I able to use wires on the pots like I am on the jacks / power to place them wherever I want on whatever custom enclosure this PCB board is in? What about the LEDs in that last picture?

Thanks for reading.

Shot in the dark, but looking for a 4053N IC (Multiplexer) for a Befaco delay build. Checked mouser and digikey and they don't seem to stock any through-hole versions. Anyone sitting on an extra that I could pay you to stick in the mail? Thanks! Brian

Still modding out a Sparkpunk synth And Ive run into a couple noob questions that my brain is too fried to wrap itself around, and I was wondering if the community could lend me a hand? Here is the [Schematic] (https://cdn.sparkfun.com/datasheets/Kits/sparkpunk-v13.pdf)

1st. Quandry, I want to replace the momentary illuminated push button "trigger" switch with a ON-OFF-(ON) toggle switch. Can't think of where to solder the wires from the 3 leads of the toggle. Im Also unclear as to wether or not the LED in the switch is integral to the synth. If it isnt needed I want to leave it out.

2nd. The t-Bridge filter pot, Would there be a way to use one portion of a concentric pot to substitute the stock 6 pin t-bridge pot?

Hello all! I'm working on a 4 stage sequencer based on the 40106 Hex-Schmitt Trigger and 4017 Decade counter. This is my second failed attempt due to blown 40106 chips after soldering. Does anyone have tips for soldering IC's? I can't figure out why I keep blowing them.

Facts that may be important:

I tried being very brief with soldering (<5 sec heat exposure per pin) and used low heat.

Each unused inverter has it's input to ground which is very close to V+ input and connected by 10uf and 0.1 uf caps.

I'm not using a IC socket. Soldering directly to PCB.

I tested the chip directly and I'm certain that is what failed. All other connections passed tests with multimeter.

Any help would be greatly appreciated!

Edit: Now with pictures!

Im modding a sparkfun sparkpunk synth and i want to eliminate the volume pot all together. Its a 10K. Couldnt I just use a 10k resistor in its place to have the volume at full all the time? Or do I need to eliminate the resistor and just bridge the connections? Ive tried it multiple ways and nothing seems to give me the same 100% Volume as a pot.

I've been hacking on a musical instrument for android for last 2 months. It started with basic triggering of samples, progressed to polyphony, then to amplitude envelope, to audio effects with real time control, instrument presets and other fun stuff.

Now I've reached the stage where it's good enough for other people to use. The link is here:

https://play.google.com/store/apps/details?id=com.castlewrath.hexpress

Please give some feedback if you give it a try.

I want to build a synth from the ground up. I have never built a synth. I want to learn how to build all the basic modules but I am having trouble finding schematics and explanations for how they are built. Please post your advice! thanks in advance.

I bought a volca beats with the "9-12 leds out" issue. I opened the chassis and found the expected decoupled DT317 transistor and went on with impatience and a lack of caution to nuke it when trying to resolder that microscopic part.

Can anyone identify what that component is? It's the transistor (I think) marked on the board at DT317. It appears to say 141 on the component. I'm going to find a replacement.

Thx!

Has anyone seen these before? Ive been doing some searching and can't find anything. Thanks in advance!

So I got a blank panel, because our store ordered a bunch and we got the sizes WAY of because of the confusion over HP and standard 19 inch 1U measurements, and decided that since I had just enough room in my rack to build one, why not add a microphonie to get some big booming ambient noises going?

Well I didn't want to wait for the PCB and wanted to try my hand at working from the schematic, part of my job is being able to interpret schematics for repairs and builds, and honestly unless I have the device the schematic is for sitting right in front of me so I can trace the circuits and see the components, schematics are just crazy hieroglyphics to me and building it on a strip board. So I started with the simple Microphonie v2.2 schematic found HERE

I got the thing put together and feel like I did 90% of it correctly except I don't understand two portions of the schematic which Ive outlined in red HERE. I hope the description makes sense.