Reply 221 of 236, by Dunuin
Nice, I've got an spare Raspi3+ laying around, because I build a real home server and don't need my Raspi-server anymore.
Does Munt got a API for user inputs? Its no problem to add a letter LCD and some buttons to the Pi, so it could look and feel more like the real MT-32, as long as Munt would allow that.
Reply 222 of 236, by gdjacobs
It generally doesn't require any input once the client is up. I initially patched mt32d to output text to an LCD, but the better, more modular approach has been using software layers on top to sniff and display SYSEX messages, switch to GM synth engines, etc.
Reply 223 of 236, by appiah4
Here's a video of my MUNT-Pi setup in action 😀
Reply 224 of 236, by Badscrew
Will take some time to read everything and hopefully understand 😁
Reply 225 of 236, by appiah4
One thing I noticed is that if I leave the Pi turned on overnight, and/or powercycle the computer, MT32D no longer receives MIDI messages. I believe this is a quirk related to the USB MIDI interface I'm using, but regardless, in either case I have to powercycle the Pi as well before the setup starts to function.
It's not a huge deal, but a strange quirk nonetheless.
Reply 226 of 236, by 7F20
i have gotten this up and running, but i sometimes get PCM recover, underrun errors upon exiting dosbox. So far, it hasn't been a deal breaker, but I suspect it coincides with game hangs and sound stutters I occasionally get. I set Munt to -m -i 25& to get a solid 25ms buffer (which is apparently the default for dosbox mixer) and I set all of dosbox's emulated instruments to 48000kHz (which is apparently the alsa native default).
What's your experience with these settings, and did you find that there is a correct way to arrange all of that?
Reply 227 of 236, by gdjacobs
Reply 228 of 236, by 7F20
Thanks for the reply. Yes, I am using a run-of-the-mill usb audio dongle. Pi native audio is pretty terrible in my experience.
Reply 229 of 236, by gdjacobs
USB audio issues were not uncommon and sometimes required tweaking of fast IRQ (FIQ) parameters. You can try adding fiq_fix_enable=0 to the kernel parameter list which trades off some CPU usage for greater USB I/O. Are you running dosbox off the SD card or a USB device?
Reply 230 of 236, by 7F20
I installed dosbox on the sd card, but I have all my games and such on a usb 3 memory stick. With my raspi 3, I just used an ssd on the usb ports, but now using the 4, so no USB boot yet. I will try adding that line to the kernel params. Sorry, but I'm new-ish to linux so just learning some of this. Could you please confirm I should add that to: /boot/cmdline.txt ?
Reply 231 of 236, by gdjacobs
Reply 232 of 236, by 7F20
After adding that line, there's been a reduction (not complete elimination) of the usb audio errors reported. Today, I finally overclocked the pi4 (mildly), and I think that smoothed things out a bit as well, or at least helped with the cpu tradeoff.
Reply 233 of 236, by gdjacobs
Reply 234 of 236, by appiah4
I might just be deaf to it but the regular Pi audio out is fine for just stereo MT-32 audio IMO. Adding a USB sound card simply complicates the setup..
Reply 235 of 236, by gdjacobs
THD is fairly high due to relatively low frequency PWM. I wish they'd spend 50 cents for either a PCM DAC onboard or a higher clocked PWM DAC. They don't need super high bit rates, but proper CD quality would be nice.
Reply 236 of 236, by 7F20
Hopefully don't sound too picky, but I am an audio centric person and the difference is pretty noticable to me.
Even if I'm getting a little tearing or a frame rate drop, it's worth it.