16-12-21, 17:33 -
a little update:
I've been working on getting this setup working with Hans' latest beta, and although I've been able to replicate my setup I now hear a large amount of clicks, pauses, and interrupts. I determined that this was coming from Alsa_in, and not pure data. very disappointing but the Alsa_in/loopback device solution was always less than ideal, and without a complete rewrite of samplerbox's audio engine I have determined that a purely software based solution is not viable going forward. I have since switched to a fully hardware solution and it works wonderfully. I've added a USB audio card with stereo in, and have the hifiberry that samplerbox uses feed into that (I believe that when I first came up with the idea of blending samplerbox with pure data Hans suggested I use two cards and I should have listened but I was being cheap
). There's zero latency and the sound is crystal clear.
I've bought a cheap behringer ucontrol uca202, removed it from it's plastic case, and mounted it along with the pi to a piece of laser cut acrylic, very tidy, I just need to make some custom length RCA cables for when I build a case. The ucontrol is class compliant so there was no need for drivers but I'm still using Jack audio to route pure data directly to that card. The card is marketed for transferring tapes and vinyl to digital, and an interesting feature is that it has a headphone monitor out, that only monitors the pre-processed input signal (as in, a separate output of samplerbox before being processed by puredata), what this means is that I can take that headphone output and wire it to left and right mono jacks, giving me 2 sets of stereo outputs, one set with just the signal from samplerbox, and another set with the samplerbox/puredata mix.
I've been working on getting this setup working with Hans' latest beta, and although I've been able to replicate my setup I now hear a large amount of clicks, pauses, and interrupts. I determined that this was coming from Alsa_in, and not pure data. very disappointing but the Alsa_in/loopback device solution was always less than ideal, and without a complete rewrite of samplerbox's audio engine I have determined that a purely software based solution is not viable going forward. I have since switched to a fully hardware solution and it works wonderfully. I've added a USB audio card with stereo in, and have the hifiberry that samplerbox uses feed into that (I believe that when I first came up with the idea of blending samplerbox with pure data Hans suggested I use two cards and I should have listened but I was being cheap
). There's zero latency and the sound is crystal clear. I've bought a cheap behringer ucontrol uca202, removed it from it's plastic case, and mounted it along with the pi to a piece of laser cut acrylic, very tidy, I just need to make some custom length RCA cables for when I build a case. The ucontrol is class compliant so there was no need for drivers but I'm still using Jack audio to route pure data directly to that card. The card is marketed for transferring tapes and vinyl to digital, and an interesting feature is that it has a headphone monitor out, that only monitors the pre-processed input signal (as in, a separate output of samplerbox before being processed by puredata), what this means is that I can take that headphone output and wire it to left and right mono jacks, giving me 2 sets of stereo outputs, one set with just the signal from samplerbox, and another set with the samplerbox/puredata mix.