RuneAudio 0.4-beta for Raspberry Pi2/3

[Vhond]

[salzi]

I cannot get airplay working. Playing from NAS and radio works but somehow airplay doesn't give signal. I've tried to change mpd settings by ssh and googled a lot and tried different rune versions but nothing helps. I noticed is that rune says I've rpi 2, but I've rpi 3 b V1.2. May that be a problem?

[gearhead]

The Pi3 will boot with a Pi2 image. That is not the problem, If your pi boots. I was never successful in getting shairport to work reliably. What I did was uninstall shairport and install shairport-sync. This step means that the UI will not control shairport-sync and you will need to configure it from the command line. The configuration file is in /etc/shairport-sync.conf and the way to start it is by using systemd service files: i.e. 'systemctl start shairport-sync'. There is a link above where Frank outlines how to install shairport-sync.

[ARFrater]

HI any thoughts on the new RASPBERRY PI 3 MODEL B+ is is a worth while upgrade and will the RuneAudio 0.4-beta OS/Image run with the new Pi.

Thanks

[janui]

Hi ARFrater,
No, it won’t work.
See here: rpi-3-b-is-now-out-t6275.html#p24848
and here: post24891.html?hilit=janui#p24875
There is a version on the way which works.
Is it worth the upgrade? Probably not if you already have a Pi B2 or B3. However, it is more powerful and the same price as the older models, so no reason not to use it when a RuneAudio version is released which supports it.
janui

[ARFrater]

[arnaldo]

hi guys, i have a problem.
i have 04-beta with the last kernel (4.14.39), raspberri pi2(08).
in usb is ok, i would try to connect my dac via spdif.
I have a Allo Kali reclocker and a Digitale Interface I2S vers SPDIF BNC WM8804

which driver i have to use?
thanks,
Arnaldo.

[Dave Platt]

Hi, arnaldo! I don't know for certain, but after looking at the documentation for the WM8804 and the Kali, it looks to me as if using the HiFiBerry DAC driver would be a good place to start. This driver seems to work with a lot of DACs, as it appears to use the I2S interface in a fairly "vanilla" fashion - the Pi is the I2S clock master, and a 24-bit/sample frame format is used.

I have to question, though, whether the approach you're choosing is an ideal one. The Kali is going to be re-clocking the signal as it comes out of the Pi, and before it goes into an I2S-to-SPDIF converter. Converting the signal to SPDIF is necessarily going to merge the separate clock-and-data signals of I2S, into the single composite signal carried by SPDIF. When the SPDIF signal reaches whatever device you're sending it to (presumably a DAC or A/V receiver that contains one) this device is going to have to separate out the clock and data again using an SPDIF receiver with its own PLL... and this process can (and I fear it will) reintroduce the same sort of clock jitter that the Kali is intended to get rid of.

Any sort of re-clocking of a digital audio signal is probably best done as close to the final digital-to-analog conversion as possible - which in this case would mean after the SPDIF step.

The Kali seems to be made to be used immediately before a (slave-mode) DAC, so that the DAC can take full advantage of the stability of the re-clocked signal.

[Dave Platt]

Just wanted to report a newbie success with RuneAudio here.

I played around with Rune a bit on an old Beaglebone Black I had sitting around, liked it, and decided to build a more modern configuration that could take advantage of the improvements in 0.4 beta. I picked up a Pi2B on eBay and loaded it up - it worked very nicely with an old Creative Extigy USB audio box. I decided I wanted to build something more self-contained, so I bought an inexpensive I2S DAC module (based on the TI PCM5102A chip) and an AdaFruit HAT prototype board. I also dug out a nice metal case for it (an old Black Box GPIB-to-serial converter that I could junk).

Everything soldered together quite nicely. I put the DAC module in the center of the HAT board. For power, I decided to use a multiply-regulated approach for stability and low noise. The box takes in a 12-volt-DC supply from a fairly hefty switching power supply brick that goes through a 1-amp polyfuse and switch. This is then brought to a pair of separate 5-volt linear regulators - a 78L05 on the HAT which powers the DAC module, and a 7805-equivalent on a heatsink on the floor of the case which powers the Pi itself. Both regulators have 22 uF 'lytic caps wired across their inputs, for stability. The DAC module works fine with the HiFiBerry DAC driver, and ALSA reports it's being fed a 24-bit signal (which should mean that any quantization noise from the use of the ALSA softvol control is down well below audibility).

The resulting box looks good enough to pass muster, and it sounds fine (I'm using it with a small in-the-bedroom system, which is quality-limited by the speakers). The system has a dead-quiet background - there's no trace of digital switching noise, buzz, or hum that I can hear. Although the linear-regulation approach is somewhat energy-inefficient (the 7805 is dropping about 7 volts, at whatever current the Pi is drawing) the energy waste is negligible - the box isn't more than faintly warm to the touch even after playing Ogg Vorbis recordings for an hour.

I'm just hoping I don't get bitten (or bitten too frequently) by the notorious "Pi corrupts the SD card" problems. Gotta back up early and often.

My thanks to all who have worked on RuneAudio - it's a nice distribution and an excellent tool.

[Kilgore]

Any photos Dave? Share the love!