Features
- Passive attenuator, approximately -20 dB
- A small dongle that can be patched between modules or devices
- Bidirectional – plug it in either way around!
Notes
I made two of these small attenuator dongles for my Eurorack system because I kept running into situations where I want to knock down the signal level by a large amount. I have a fancy attenuverter module but I just wanted something small and simple that would leave the attenuverter free for more important jobs.
My particular reasons for using this attenuator are:
- Using a tuner (or other external device)
- I have a tuner that has trouble with the signal level straight out of a Eurorack VCO, so I keep one of these attenuators plugged into the tuner.
- Bad design choices
- I made the pitch mod inputs on my oscillator modules way too sensitive. Even though there’s an attenuator control on the input, it’s hard to get a reasonable vibrato when I patch in an LFO. Sending the LFO through this attenuator gives a much better range of adjustment on the pitch mod input, for most purposes.
The device is assembled on a small piece of stripboard PCB. (See the layout diagram below.)
Please note that I am a hobbyist, not a trained electronics engineer. No guarantees!
![Stripboard layout diagram](schematic.png)
![Stripboard layout diagram](layout.png)