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PhenixRising
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Joined: 07/11/2023
Location: United Kingdom
Posts: 1134

Posted: 03:26am 06 Apr 2025

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Very cool and following with interest

al18
Senior Member

Joined: 06/07/2019
Location: United States
Posts: 222

Posted: 02:59am 25 Apr 2025

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PilotPirx said @lizby

synth

Looking forward to you releasing your program for the U178.

I ordered a U178 and a U187 today from Digikey. There are 12 in stock of the U178 and 19 of the U187 in stock at Digikey’s US warehouse. Digikey charged a 10% tariff for both of these items. If you want one of these modules, suggest you order them before they go out of stock. FYI M5Stack is based in China, and the company states there will be a $90 tariff for items shipped on May 2. For items shipped after June 2, the tariff will be $150
Edited 2025-04-25 13:09 by al18

stef123
Regular Member

Joined: 25/09/2024
Location: United Kingdom
Posts: 83

Posted: 08:12pm 25 Apr 2025

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Some Years ago i had built a Synthesizer around this Chip, this is the second Version. The first Version was buld into something like a 19" Rack. Edit: I have to correct myself - the first Version was built into a dead Roland EG101 "Groove-Synth", adapting my PCB to the remaining Guts of the EG101 after removing its dead Sound-Board. But i was not pleased, because i had too few Realtime-Control possibilities.

Please excuse the excessive usage of Hot-Snot, i usually ran (and do run) out of pbc interconnection plugs, so everything was hand soldered.

Currently it makes some trouble after powering it up. It was never fully finished, but running. This Synthesizer features "stacking" of multiple sounds at the same time. I've chosen four, so you can get four different sounds with four different filter settings, ADSR envelopes and so on. They can be set up individually, or all together at once.

It was programmed in Assembly and featured two 8051 Controllers, one for handling the Synth/Midi/LCD/Main Program, the other one handling the KY040-Encoders. The SAM2695 Board was quite expensive back then, i recall 40 Euros. At least with a (simple) integrated amplifier.

I was in need something like a Faceplate (the front resembles something like a Matrix for Parameter access), but never got hold on one. Meanwhile i have a cheap Chinese Milling machine, but not enough Material for testing it out and my Machine isn't able to mill the requested size. I guess that i have to do (again) a new Version.

The SAM2695 is a fine Chip for its price, but the given boards have, as known, the Problem that they only use Midi UART and that slows down the entire Data Transmisson process drastically. I had to merge the incoming Midi stream from my PC with the parameter change commands, which were generated when i turned the knobs.

The Chip itself -has- the ability to be accessed via a parallel port, but as said, current boards do not make usage from it.

The Chip seems to have also some issues. It features a Reverb and Chorus Unit, but somehow it doesn't quite get it sometimes. In order to change a program i had to transmit all parameters to the Chip, but somehow it always forgot to "apply" those settings to the Rev&Cho - Unit.

There are very few usable sounds built into this Chip; consider its more or less being produced for Toy Keyboards. SAM produces more enhanced Versions, but they are barely offered to the normal market.
Edited 2025-04-27 04:49 by stef123

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