Performance vs Raspberry Pi version

[ChKK1963]

Thinking about building this ASAP, is there a substantial performance difference between the Pi 3/4? What is the total number of concurrent voices I can expect?

Does it make any difference for this project if the Raspberry Pi has 2, 4 or 8 GB and of memory?

[probonopd]

Welcome @ChKK1963. From my experience:

• Raspberry Pi Zero and 1: Only one Tone Generator (TG), no effects (reverb etc.); "like a DX7"
• All other models: 8 Tone Generators (TG) and effects are available, although using more than 4 concurrently might bring the Pi 2 to its limits
• Pi 4 is best in order not to get stuck USB MIDI keys which can happen (very rarely) under certain circumstances on the other models, see Notes get stuck while quickly playing with USB MIDI keyboard controller #48

The available RAM does not make a difference.

[ChKK1963]

Thanks, so a 2GB Pi 4 sounds like the best option.

With 8 TGs in use, what is the number of voices per TG or in total to expect? The original TX816 had 16 per channel …

[probonopd]

Same:

MiniDexed/src/config.h

Lines 42 to 46 in 7519da5

	#if RASPPI == 1
	static const unsigned MaxNotes = 8; // polyphony
	#else
	static const unsigned MaxNotes = 16;
	#endif

If you need more, you could play with that value in the code.

[ChKK1963]

👍