Apologies, slightly off-topic, but I mentioned this earlier in the thread, and there seemed to be a little interest...
I now have a working Raspberry Pi + ma12070p-based sound server. The gist is described above, literally just a Raspberry Pi and an ma12070p amp board (and power supply). Audio is sent to the device over the network via PulseAudio. Merus/Infineon actually provide a native Linux driver for the ma12070p which exposes a number of controls and status through ALSA (I originally thought I'd be hacking my own I2C code to do this, but having it all pre-made was a nice perk).
I started by using the Infineon ma12070p reference board for the prototype concept. See here. The reference board is barely bigger than a postage stamp! I ran with this for a while without issue, and went ahead and designed my own ma12070p board. I built up my board last weekend, and it's been running successfully since. See here. I just placed a parts order for a "version 2" of my board, which is basically just a physically larger board that allows the use of overkill RLC output filter components along with a couple other small tweaks.
I'm not sure how one would go about measuring the performance of this design, since the "input" isn't the typical USB/SPDIF/TOSLINK, but rather an application-specific protocol (i.e. PulseAudio's wire format). Assuming I didn't make any design errors, it "should" have measured performance consistent with what's shown in the ma12070p datasheet. This is based on the fact that the design is a literal copy of the reference board (with the addition of the RLC output filter). Subjectively, I have no complaints with the sound. I'm using this in my office to drive a pair of Solstice MLTL speakers. But I fully admit to a definite "baby bias" on stuff I built myself!
It's a pretty cool chip! I'm actually planning to use the "P" version to build a DIY "sound server" for my office. In a single fairly small enclosure, I'll have a power supply, Raspberry Pi, and MA12070P board. I can send audio over the network to the RPI (e.g. from my PC) via PulseAudio, and the RPI can send audio data via I2S straight to the MA12070P chip. I can also do digital volume control, change power management profiles, and some other fun stuff via I2C serial command from the RPI to the chip. Still waiting for all the parts to arrive, so only at the planning stage, but I expect to get something working fairly quickly.
@MattG
This could be quite an interesting project!
Do you plan to document it in any way? Opening a new thread here or in any other forum (DYIAudio, etc.)?
Please, keep us informed!
I now have a working Raspberry Pi + ma12070p-based sound server. The gist is described above, literally just a Raspberry Pi and an ma12070p amp board (and power supply). Audio is sent to the device over the network via PulseAudio. Merus/Infineon actually provide a native Linux driver for the ma12070p which exposes a number of controls and status through ALSA (I originally thought I'd be hacking my own I2C code to do this, but having it all pre-made was a nice perk).
I started by using the Infineon ma12070p reference board for the prototype concept. See here. The reference board is barely bigger than a postage stamp! I ran with this for a while without issue, and went ahead and designed my own ma12070p board. I built up my board last weekend, and it's been running successfully since. See here. I just placed a parts order for a "version 2" of my board, which is basically just a physically larger board that allows the use of overkill RLC output filter components along with a couple other small tweaks.
I'm not sure how one would go about measuring the performance of this design, since the "input" isn't the typical USB/SPDIF/TOSLINK, but rather an application-specific protocol (i.e. PulseAudio's wire format). Assuming I didn't make any design errors, it "should" have measured performance consistent with what's shown in the ma12070p datasheet. This is based on the fact that the design is a literal copy of the reference board (with the addition of the RLC output filter). Subjectively, I have no complaints with the sound. I'm using this in my office to drive a pair of Solstice MLTL speakers. But I fully admit to a definite "baby bias" on stuff I built myself!