Cat Keys - a synth interface for the playdate

I have had a bit of a break from working on Playdate stuff, but lately I have found the spark to make something again. Which lead me to this cat based synth, I wanted a friendly "character" to greet you whenever you want to play with it.


As a big synth lover I felt the idea of a fun interface for some of the synth features on the playdate, I realised I already knew some of the synths from my OP-1 and OP-Z by teenage engineering.
Ideally I want some different things integrated:

  1. a page for synth settings and freeplay
  2. a page for LFO related stuff - should be able to controll both synth parameters and filter parameters
  3. envelope
  4. a sequencer for synth
    -- all above I have integrated, but with features missing
  5. filters
  6. Arppegio settings
  7. a drum synth (based on the noise synth maybe)
  8. a drum sequencer.
  9. a button or a dail for a little extra spice - not 100% sure how to name this yet.

Below are some videos of the synth in use, I put it through a "tc electronic - flashback" for some delay effect:

Link to in use video 1
Link to in use video 2

also some earlier versions:
My original idea was to have it all on one page, but in the end I felt it was kinda besides the point to put a "physical" synth on the device.

almost as it is now, but I didn't feel the face was fun enough

Also here are the very first sketches for the idea:

With that said, I hope to post updates whenever I have the time to make new stuff, progress might be a bit slow I am still struggling with the coding side of things - so might drop some questions here as well.


Love the cat face, adds a lot of character!

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This looks great so far! I love the idea of making it fun, that it doesn't have to look like every other synth and that the screen changes based on what you are doing, like the OP-1.

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Which is ironic because TeenageEngineering is the one the designed the PlayDate.

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@orkn Thanks a bunch Scott! Yeah I hope it will make it more fun. I want to make it "dance" or bounce at least to the tempo when in sequencer mode. - Also wondering how I can represent the different filters in a fun way.

@posburn Thanks! Yeah exactly, massive fan of TE! I love my TE synths :smiley: I also want to see how little actual synth info I can get away with putting on screen, and how much can just be getting the feel for how the different settings affect the sound - much like the screens on the OP-1.

@catbeard I discover the playdate originally exactly because of TE. I just think it is amazing that the people at playdate has made it this easy to design games and tools to put on it, and spend the time to make such wonderful synth features available.

Yesterday I got a bit stuck on getting the filters and LFO to work together like I would want them to, but I hope to make some progress today.

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Made some progress on getting the lfo to work with the synth today - I still have some issues with the filter not quite doing what I want - Also the lfo produces some clicks and pops, I put on a spring filter on my op-1 for effect here as well, but really I am wondering how to avoid those clicks and pops, any suggestions for what might cause it? - Is it because I need to clamp the sound somehow?

Video of said recording

A small update, made the lfo with lines and sine wave instead of just moving an image, so I can display the depth of the lfo as well:

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Looking good!! Excited to see where this will go :playdate:

Thanks Aiden, really glad you like it :smiley:
I am working on adding some life to the cat - mapped it to the gyro, but unfortunately my playdate is in for repairs, so I can only screen capture:

I want the face to move with tempo, and maybe look at the key selected and such as well eventually.


I am back with an update!
I suffered some pretty frustrating setbacks - first my crank broke and I had to send the PD in for repairs (thanks for the quick help to playdate btw), then I realised there was some issues with the Bpm of the sequencer - and fixing it created an endless stream of new problems, among them an endless amount of fatal crashes with the way I was using the sequencer :frowning:
After a while I decided to go back and rewrite / clean all the code and try some new approaches. It was a tough ride, but worth it, because I have a much better program now! Also significantly more user friendly!

In any case there is a video of the synth in action here:

it is now possible to actually make tunes! - delay is still my guitar pedal - but I am thinking I need an fx page as well.

Still lots of small weird issues - I also still want to integrate arpeggio and then obviously my drum sequencer need to get back in.