I opened up my Radio Shack "Electronic Reverb Control" delay unit and replaced jumper JP3 (which is in series with the original "delay" fader) with a 1MΩ variable potentiometer, as well as a 100kΩ pot instead of R21, which is the feedback resistor for the delay circuit opamp.

In the video I am running my Korg MS-10's output into the (noisy, but beefy) unit's microphone input and play a few notes. The larger knob at the top is the extended delay time, and the smaller knob underneath affects the feedback.

I captured the output with my soundcard, but applied no processing to the audio.

For reference, I used the following tutorials as inspiration:

https://forum.ableton.com/viewtopic.php?p=426956&sid=8d60bdcdd0f2933aa8a5ce3da7650b8f#p426956

and

http://clacktronics.co.uk/2011/realistic-reverb-noismaking-mods.html

Since I just got myself an ST7920 128x64 LCD display, I had a go at building Mirko Pavleski's oscilloscope, following the instructions at https://create.arduino.cc/projecthub/mircemk/diy-10hz-50khz-oscilloscope-on-128x64-lcd-display-52ecfe.

There is a couple of adjustments that need to be made, as outlined in goldenxxxl's comment on the page, but after that it works beautifully.

In this video I am trying it out with my Korg MS-10, demonstrating triangle, sawtooth and pulse waveforms.

Just a quick video showing the range of delay effects that are possible with this delay.

For more info and a slightly more musical application check out this video: https://www.youtube.com/watch?v=acUnCFN49WQ

In a previous video I triggered two drums voices on my Tama TAM500 analogue drum module from a Behringer RD-6. Today I am using a Raspberry Pi Pico to trigger all five voices via MIDI, four of which respond to velocity data.

Currently the MIDI notes for each drum are simply hard coded. When a MIDI note is received its velocity gets translated to a voltage between 0 and around 160mV by a dedicated MCP4725 DAC, which seemed to give the best velocity response. Anything above that triggers the drum channel at full intensity.

I am using my Roland JP-8000's arpeggiator (connected to the Pico via DIN MIDI) to trigger the 5 drum sounds on the Tama drum module.

To visualise what's going on I set up the TM1638 LED&KEY module to light up 0-8 LEDs depending on the current note's velocity, and to display "BD", "SN", "HH", "HI" and "LO" in the 7-segment section, depending on the drum currently playing.

The main audio out (mono) of the Tama goes into the NTS-1 for a tiny bit of distortion to fatten up the sound and a smidgen of reverb for stereo-ness.

In addition, the bass drum's direct out goes into my "100 Kinds Effects DSP Digital Reverb Module DC 5V Karaoke Reverberation Mixer Effect Board" I got from AliExpress for a short stereo delay (this is 100% wet).

The snare's direct out goes into my PT2399-based delay unit for some subtle fast delay.

For more details on the hardware setup check out my series on MIDI to CV here: https://axwax.eu/electronics/raspberry-pi-pico-as-midi-to-cv-converter/ and my post about the TM1638 LED&KEY here: https://axwax.eu/electronics/tm1638-ledkey-based-midi-visualiser-on-the-raspberry-pi-pico/

I'll try to post the code eventually, once it is a little bit tidied up.

A honey bee is making good use of a Phacelia tanacetifolia plant that is growing in our garden as part of our bee friendly green manure mix.