I’ve been building Pi-based Roon endpoints for years, as well as a streamer using the Hifiberry Digi+ Pro. I’m now getting a bit more ambitious and am building a streamer that can output via i2s and/or USB to my DAC (the DAC itself upsamples to 32-bit PWM, so I’m not bothered about DDC functionality).
To that end, I’ll be using the Pi2aes 2.0 Pro HAT with a Pi 4. So far so good, but I’m looking for advice on:
a decent hi-res colour OLED display to use with it
a linear PSU to drive it
A case for the above
the best distro to drive the whole thing, including the display - I currently use Ropieee and DietPi.
I’ve looked at the Ian Canada boards, but can’t find an overall explainer for each.
Simply that - the DAC itself upsamples all input to 32-bit Pulse Width Modulated at (IIRC) 3.16MHz, so there’s little point in doing any DDC, in hardware, Roon or HQPlayer upstream of the DAC - just feed the native stream (PCM or DSD) into the DAC.
Pulse Width Modulation consists of a sequence of equal-amplitude pulses with variable width, so that’s basically a 1-bit system, not 32. Also, 3.16MHz is a strange frequency to use in audio, as it’s not multiple of either 44.1kHz or 48kHz. What DAC is that?
Yes, PWM is 1-bit. What I should have said is that it upsamples to 32-bit/3.125MHz and THEN converts them to noise-shaped PWM. I did the math and the 3.125MHz makes sense (my bad memory dredged up 3.16). It’s a Mola Mola Tambaqui.
Thanks. 3.125MHz is still a weird frequency to use (70.86x44.1kHz and 65.10x48kHz), but that’s what they say. It’s one of the best DACs, so I don’t think I2S will improve anything over the Pi’s built-in USB with wall wart.
That’s exactly the purpose of the experiment - spending a few hundred $/£ (rather than thousands) to see if streaming platform makes much of a difference front-ending that good a DAC. The Tambaqui actually reports itself as having a Pi module as its network interface, so we’ll see. If it doesn’t make much difference, I’ll have a) learnt a bit more about building streamers and b) have a system I can deploy on one of the other hifis around the house. When I was auditioning DACs, I listened to both the Bartok and Chord DAVE directly through their own network interfaces and via an Auralic Aries G1.1, I was surprised at just how much difference to the SQ the streamer actually made. And, no, I don’t have a full explanation for that. Yet.
Actually, I had them swapped over blind, so I didn’t know what was in the chain.
I’ll always make my own decisions about how much to spend - when choosing a DAC, I started fairly low, and worked my way up, with the intention of stopping when I hit the point where the law of diminishing returns really started to kick in. I had precisely zero intention of spending that much on a DAC, but it really did stand out head and shoulders above everything else. To the point where my partner beamed in from the other end of the house with the exclamation of, “whatever device you’re playing, that’s the one!”
Umm. behavioural ecologist, AI researcher & data scientist here. Spent 40+ years on conditioning data sets, separating out perceptual bias from empirical models, so I kinda hope that I’ve got the hang of it by now…
Very interesting credentials! The people who show up in this forum have such interesting and varied backgrounds.
I did undergrad studies - and extensive, grant-funded research - in the Social Psych domain and followed that with 30+ years of tech including quite a bit of data science in one form or another. In spite of that, I still don’t trust my ears or my brain and I particularly don’t trust myself when I have made investments in the outcomes. I know too much about dissonance theory for that. But, that said, your project sounds fun and interesting and there is no bad outcome. I hope you keep us posted.
Can you clarify what you’re trying to accomplish with the hi-res display you describe? RoPieeee supports the low-res, touch capable Raspberry Pi screen but that doesn’t sound like what you’re looking for.
Thanks - exactly what I’m looking for. My intention is to start simple, see if that makes a difference, and then add modules to test the next step - that site looks ideal.
Regarding your original post, I also built a streamer using RPI4 and Pi2AES Pro 2.0 HAT to feed my Chord Qutest.
For the DC power, I used two Sigma-11 power supplies (one for the Pi2aes and the other for the RPI). I build them myself using pcbs from AMB Audio, but I’ve also seen them for sale pre-built.
I’d originally only planned on using one for the Pi2AES HAT, but I found there was a noticeable improvement when powering the RPI from a second Sigma-11 instead of the more traditional RPI wall-wart.
The bottom line is that I am very happy with the performance. To my ear, the sound quality is significantly better than directly connecting the Qutest over USB to my ROCK server. Pictures are below…
