[PROBLEM] WEMU plays on computer but not on MoOde

[TheOldPresbyope]

@eracerr 

The lower-bound sampling rate I usually see listed for high fidelity DACs is the CD standard 44.1 kHz. This station, unlike the others, is sampling at half that rate and the i2S driver (the overlay) is telling ALSA/MPD/moOde that this rate is fine as is.

According to TI docs, the DAC chip used on the PecanPi DAC board can deal with a sampling range from 10 kHz to 196 kHz so 22.05 kHz is ok in principle. I'm still suspicious.

Here's a quick test of my hypothesis -

What happens if you go into MPD settings, enable SoX resampling, and set the sampling rate to 44.1 kHz? Can you play WEMU and hear any output now?

Of course I could be driving beyond the range of my headlights here, in which case I'll step back.

Regards,
Kent

[eracerr]

@eracerr 

The lower-bound sampling rate I usually see listed for high fidelity DACs is the CD standard 44.1 kHz. This station, unlike the others, is sampling at half that rate and the i2S driver (the overlay) is telling ALSA/MPD/moOde that this rate is fine as is.

According to TI docs, the DAC chip used on the PecanPi DAC board can deal with a sampling range from 10 kHz to 196 kHz so 22.05 kHz is ok in principle. I'm still suspicious.

Here's a quick test of my hypothesis -

What happens if you go into MPD settings, enable SoX resampling, and set the sampling rate to 44.1 kHz? Can you play WEMU and hear any output now?

Of course I could be driving beyond the range of my headlights here, in which case I'll step back.

Regards,
Kent

That worked!  Now there is sound.  Not very good sound.... but sound.

Any suggestions on what settings to start with to improve the sound from this station but not mess up stations that don't need it?

Eric

[Tim Curtis]

Maybe try swapping in another audio device or using the Headphone port on that Pi and see if the issue might be unique to the pecan dac and its driver. Also could ask the manufacturer what rates the dac supports.

[TheOldPresbyope]

from the OP we have

It WILL play on the Rasberry Pi Zero W with Allo MiniBoss DAC

and similarly it plays here on an RPi Zero 2 W with a (USB) Creative BT-W2 adapter so I'm thinking we've already demonstrated the problem is in the PecanPi DAC / driver. 

Time for a discussion with the Orchard Audio folks. They're long on audiophilic marketing quotes but short on useful technical details.

Sampling Rates: PCM up to 192kHz

Yeah, "up to..." but what is the lowest sampling rate (which depends on the clock rates the board supports, or v.v.)? The driver claims 8 kHz to 384 kHz. That seems to exceed what I read on the TI datasheet for just the PCM1794A DAC  chip (10 kHz to 200 kHz) but, whatever it is, they should be definite in the specs given for the board.

Bit Rates: Up to 24-bit

Um, that's not a bit rate, it's a bit depth, and "Up to..." isn't enough. What bit depths, precisely? The driver claims 16-bit and 24-bit. Given the TI DAC chip used, this sounds right but they should say so in the specs for the board.

Regards,
Kent

[vinnn]

This plays OK on mine also with the Topping D70s DAC.
@eracerr, is it possible your dac is having issues with decoding a 22kHz sample rate?

Sleepbot Environmental Broadcasting is a fave channel of mine that also broadcasts at 22kHz, give it a try...
http://sc13.shoutcaststreaming.us:8218/seb,