Simple VCO

Name: Simple VCO
SKU: 20515
Price: 17.00 USD
Availability: InStock
Rating: 4.88 (8 reviews)

(8 Reviews)

Easy-to-build Saw core VCO for your Eurorack System

Designed by Electronic things... and stuff in France

2020-11-14T18:20:02.721Z-2020-11-14 19.10.11-expo.jpg

2020-11-14T18:14:20.407Z-2020-11-14 19.16.02.jpg

2020-07-15T13:52:39.737Z-vco-main-3diso.jpg

2020-07-15T13:52:39.737Z-vco-main-back.jpg

Buy with confidence.

Our Tindie Guarantee protects your purchase from fraud. Learn More

Easy-to-build Saw core VCO for your Eurorack System

The Simple VCO is a DIY friendly module, designed to be integrated into an analog synthesizer. It is compatible with the Eurorack format: 10-pin power supply connector and voltages (+12, 0 and -12V).…

About the version

The current PCB version is 1.0

Version History:

0.1: first prototype. Fully functional.
0.2: Addition of a "Fine" potentiometer. (V0.1 Front panel is compatible with PCB V0.2 without "Fine" potentiometer though).
1.0: Official release. Identical to V0.2

Options

The Simple VCO is available either as a PCB, a PCB with its 4HP Front Panel, as a Kit or Fully Assembled.

About the Front Panel

The Front panel is made with 1.6mm thick PCB material. As such, the black color may present some inherent slight irregularities.

Review Breakdown

Average Ratings

Product: (4.88)

Documentation: (4.88)

Shipping: (4.75)

Communication: (5.00)

Jasper | July 29, 2024

Easy to build, fun module!

This module is easy to build, all the steps and information is very well documented. It's also a lot of fun to build. The only 'difficulty' is getting Temperature Compensated resistors, but they're available on the internet. In my case, the oscillators are a tad unstable, which is perfect for the desired purpose of creating a drone like synth. Highly recommended :)

Response from Electronic things... and stuff | July 29, 2024

Thank you so much Jasper for your kind words and your support.
Indeed the tempco can be difficult to source. But it's not mandatory and can be replaced by a simple resistor.
About the instability you mention, it's probably caused by a variation on the power rails as the module doesn't have dedicated regulators/voltage references...
I hope you will enjoy using the VCO.
Thank you again!
David

Roberto | May 10, 2024

Simply perfect

If you want a simple stable Vco for a lot of uses this is simply perfect !
Also for beginner cause instructions are the best i ever seen in diy Projects

Zachary | June 5, 2023

Great way to learn the fundamentals

This module is super simple for a vco and doesn't add anything unnecessary or extra. Its just a saw wave, which is all you really need in most cases. The pcb is beautiful and each component is outlined on the pcb which makes it very clear and easy to figure out what component goes where. The blog articles are also cool and go deep into the theory behind it.

Also ships faster than anyone else I've bought from on the platform.

Steven | Aug. 19, 2022

Sounds great and an excellent project for a beginner

This is the first electronic project I've built and although it took me a long time (because I was being super-careful) everything went together nicely and it worked first time. The build documentation is excellent although the calibration procedure took a while just because I found it quite counter intuitive - if the sound is flat or sharp, make it worse - but it works although it takes a few iterations.

But now that I know what to do I'll be making another. I bought enough spare parts and two of these stacked will sound awesome.

Eugene | Sept. 26, 2021

Great

Very stable VCO. Easy to assembly and cheap in parts. Awesome! Make sure you get proper transistors and TEMPCO.

Kalle | May 5, 2021

Delivers the simple bleeb bloobs

Cheap 1v/oct oscillator is rare. This is easy kit for basic module for beginner. The low price gives you chance to build row of 10 if you wanna drone your way. My only trouble was sourcing some components. Potentimeters used in the module are not that common in Finland. So I had to modify another type of pot.

Response from Electronic things... and stuff | May 5, 2021

Thank you for your feedback!

The potentiometers are the regular 9mm "Alpha" Right angle/PCB mount.
They are the *de-facto* standard in all Eurorack Modules nowadays.

You can find them in numerous places on Internet: Thonk, Synthcube, Musikding, Smallbear Elec, Mouser, Tayda, etc...

https://www.thonk.co.uk/shop/alpha-9mm-pots/
https://synthcube.com/cart/synth-diy/parts/potentiometers/alpha-9mm-round-shaft-pc-mount-pots
https://www.musikding.de/Potentiometer-9mm_1
https://www.mouser.com/Search/Refine?Keyword=rd901f
https://www.taydaelectronics.com/potentiometer-variable-resistors/rotary-potentiometer/linear.html

There are many compatible brands (BI/TT, Alps, etc).

And if the value you're looking for isn't available, you can use other values as well, as long as the circuit can tolerate that change. As a matter of fact, many volume/voltage divider circuits are insensitive to the absolute ohm's value. In these circuits, only the ratio matters.
For instance, if you can't find R2 (100k), you can substitute it with a 10k ohm potentiometer. But in this case you must also modify R1 and R3 values: if R2 value has been divided by 10, then R1 and R3 values must also be divided by 10: 1k ohm each.

Have fun!

Daryll | March 8, 2021

Superb VCO

Ok , so its a bare minimum VCO , but that does not distract from the Quality , it took about a hour to solder up , plugged it in , worked first time , calibration was easy
Coupled with the LFO , we have a cheap , but excellent VCO , with modulation from the LFO , what more can you ask for , parts count is low , with easy to obtain parts , you could build several of these as a base of a monster synth , and it wont cost the earth , all together a very useful project , and a must have VCO