A DX7 (Fm synthesis) replacement with Dexed on a Teensy

The folder structure is in the link i sent above. When it is freezing at boot, it probably is not an issue with the SD Folder. It should boot even without SD Card. I guess your boot issue is DAC related since the firmware expects the Teensy Audio Adaptor, not a 5102 by default.
It can be reconfigured, but then you have to compile from source.
Only a guess. It can have other reasons.
 
Has anyone in the UK got more MicroDexed-touch PCBs than they need? :rolleyes: Thinking of putting one together at some point, and it seems silly to order 5 when someone may already have one lying around.
 
That's interesting:


A big Piano manufactorer has a FM module in his program, which specs are very close to Synth_Dexed / MicroDexed - only some years after I asked them how I could integrate it into their piano (I asked the specs for their internal bus). No answer from them, but they now sell this module...

I would be very curious to know what software runs on it and if the hardware is Teensy-based...
 
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C0d3man said:
That's interesting:


A big Piano manufactorer has a FM module in his program, which specs are very close to Synth_Dexed / MicroDexed - only some years after I asked them how I could integrate it into their piano (I asked the specs for their internal bus). No answer from them, but they now sell this module...

I would be very curious to know what software runs on it and if the hardware is Teensy-based...
Click to expand...

I was thinking something similar about the SMK37PRO but then was very disappointed about of what i found inside the instrument (nearly nothing) only a tiny custom "unbranded" chip.
 
positionhigh said:
I was thinking something similar about the SMK37PRO but then was very disappointed about of what i found inside the instrument (nearly nothing) only a tiny custom "unbranded" chip.
Click to expand...
Synth_Dexed can simply be used without any hardware dependeny, so nearly any 32bit uC can be used... when removing the filter code also without FPU.

It also runs on a RPi-Pico (with limited polyphony)...
 
Yeah.. Yamaha engineers implemented clever tricks to even avoid multiplication. Their custom FM chips did just additions and ROM lookups.

The first ROM was a log-sin waveform table, containing one quarter of a sine wave, 256 samples
long. The second ROM was an exponential table, 256 samples long. Original FM chips produced sound without any multiplications, using the formula that conceptually looked like this (only additions and lookup):

out = exp(logsin(phase2 + exp(logsin(phase1) + gain1)) + gain2)

Quite an amazing piece of engineering:

www.righto.com

Reverse-engineering the Yamaha DX7 synthesizer's sound chip from die photos

The Yamaha DX7 digital synthesizer was released in 1983 and became "one of the most important advances in the history of modern popular mu...
www.righto.com www.righto.com
 
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