Raptor Computing Reveals More Details About Their Blackbird Low-Cost POWER9 Board

[starshipeleven]

I have a Supermicro workstation board from about 6-7 years ago with noisy sound. It's definitely not low-end, nor old enough for that to be an excuse. I think sound quality just wasn't a priority for them. I imagine one would have better luck with gaming-oriented boards.

Workstation boards only need basic audio, as they either aren't working with sound at all (so basic audio is fine) or if they do work with sound they will 100% have dedicated sound cards costing more than half the cost of the motherboard (so the onboard audio is not used at all).

[coder]

Workstation boards only need basic audio, as they either aren't working with sound at all (so basic audio is fine) or if they do work with sound they will 100% have dedicated sound cards costing more than half the cost of the motherboard (so the onboard audio is not used at all).

Yeah, I think they must've regarded onboard audio as sort of a checkmark feature, assuming it would probably be used only with cheap little speakers.

Its toslink output is fine, so I just feed that into my outboard DAC. The trick is usually to make sure you have all of the analog inputs muted. I can tell if the audio is bit-perfect, based on whether my DAC detects a HDCD signal, when I play a disc or flac that has it. IMO, that's pretty much the best use for it.

[coder]

None of that crap, it's still an IBM thing, but not a Power https://en.wikipedia.org/wiki/Z/Architecture

Okay, so not ARM64?

[chithanh]

So you think motherboard manufacturers are able to implement USB ports at 5 Gbps or more, but a stereo out is too hard?

It's actually hard. Modern data links are quite robust against disturbance as long as electrical specifications are met. Together with FEC and similar, getting your audio data digitally via USB and converting it to analog only in the loudspeaker may deliver much better results. Smartphones lead the way.

Do note that some boards like Raspberry Pi even drive audio jacks without analog circuitry by using PWM. This used to sound awful(ly?), but more recently they have reached acceptable quality with a sigma-delta audio driver.

[starshipeleven]

Okay, so not ARM64?

It's architecture is called "s390" in the Linux kernel makefiles, and as you can see that arch supports up to IBM's z14 mainframes, the latest stuff.

https://github.com/torvalds/linux/blob/master/arch/s390/Makefile

That's.. not ARM in any way, shape or form.

[coder]

Do note that some boards like Raspberry Pi even drive audio jacks without analog circuitry by using PWM. This used to sound awful(ly?), but more recently they have reached acceptable quality with a sigma-delta audio driver.

This is roughly how Class-D amplifiers work. It's a cool idea to have the signal remain digital until amplification (making it easy to do digital domain crossover and equalization), but the technique has traditionally been relegated to lower-end products. It's also very efficient.

https://en.wikipedia.org/wiki/Class-D_amplifier

[coder]

That's.. not ARM in any way, shape or form.

Just wanted to be clear on that point.

Rereading Dawn 's post, I see now that ARM64 was referenced in addition to IBM's z-mainframes. The idea of them using ARM in their mainframes (last November) blew my mind.