I bought this small module for few € and made some modifications
the first modification was to remove the resistance R4 and replace it with a potentiometer of 100k to manage the Pitch of the recording
(Possibility depending on the position of the pitch to record about 20 seconds, and
can not record in pitch position too high ! )
with the plugs (or there is a jumper) by soldering a switch you can select One shot (gate/trig) or Loop.
Solder wires to the pins of the mini switches in order to add switches usable from your box / panel
the same thing for the led : removed the led indicating the end of recording and added the length
again the same thing with the microphone (removed and add length)
I also added a power switch with an indicator led
add body contact on pot pitch
after, you can add a lot of things ( jack out, LFO with vactrol on pitch pot, audio in, oscillator with LFO, touching patch with CD4040 …)
Very nice stuff which sent me scurrying to AliExpress — debated whether to get some boards for bending or just some isd1820 chips. Decided to go for bending to start with.
yes it’s a good chip, I did that in boxes at the time, but I think we could consider it directly in module with a panel and all that goes well … to follow
like our PT2399
I also have some sequencer or others that could have been good modules with the back, but after the bending circuit it was my box period
luckily most can be triggered
I think that it is necessary to reduce the incoming signal to reach a suitable audio signal and to amplify it in output (as for the Stomp Box Adaptor), on my box i add a input pot and an output pot, it may be enough to lower the signal,
but some here could help you better i think
Nice! I’m working on an ISD looper right now as well.
In case you haven’t seen it there is some good info on the Bastl Instruments site with some good details and modifications.
One thing that bothered me about this module is that I could find almost no documentation of the ISD1820 chip itself. I finally tracked down a detailed datasheet for the Nuvoton ISD1806 and ISD1810, here. Maybe that’s close enough. It’s not even clear whether the ISD1820 is a Nuvoton design or someone else’s knockoff.
DigiKey lists the ISD1810 as obsolete. No mention of the ISD1820.
Over here there’s a design for what appears to be a functionally similar module, with schematic, parts list, and PCB layout, based on the Nuvoton ISD1932 or ISD1964 chip. There’s a datasheet here. DigiKey sells these chips for $5.21 and $6.24 respectively.
Nuvoton seems to make about a gazillion record/playback chips, if you’re in need of a rabbit hole.
Edit to add: The 1700 series looks particularly interesting, because unlike the 1800 and 1900 series apparently, it does have an input designed to take a single-ended analog signal (in addition to a differential microphone input). And there’s an ISD1760 module for $6 here:
Compare to our ISD1820 Modules, it has following adavantage:
Longer recording time and mutiple message!
Controlled not only by buttons but also SPI from MCU
I made a very simple version for my son (2.5years)
Just record, and play and the potentiometer for pitch. My first circuit bending project!
Could be a bit louder, but otherwise it works great!
Thanks for the inspiration!
I’m thinking of doing a project like this. So, if I want to add some springs or something for a bit of lo-fi reverb; is the consensus to put the mic on the springs or near the springs. Or do I put the speaker on or near springs? Or is this too low power to generate extra vibrations?
Here the double micro switch in place with the pot and i add also another switch to select Trigger or Gate for the external control (modular in the vid)
I play with fun on a long time this afternoon and i realized that I could also pre-record the effect and add it again afterwards, doubling it in a way for more crazy bleep bleep.
