Use a Raspberry Pi endpoint without a preamp?

Audio Gear Talk
1

I have to ship my VTL tube preamp off for repair, which motivates me to use Roon more than just to a Chromecast boombox. I assume I can get a Raspberry Pi + DAC combination, install some Roon endpont software on it, and plug its RCA outputs into my power amps. (Without a phono input or multiple audio sources, who needs an expensive stereo preamp?)

Do these RPi endpoints have hardware controlled volume, and/or is there some way in Roon to limit volume coming out of a device? My power amps are 450 W monoblocks, easily capable of blowing my speakers and fuses if something goes wrong (and it’s computer software and hardware, so… :wink:).

I welcome any hardware recommendations. I’m willing to tinker a bit with software, less so with hardware (no soldering!), and am hoping to spend less than $500 until I hear what bang for the buck I’m getting. My power amps also have XLR inputs if anyone thinks that makes an audible difference over a 2 meter run to each power amp. Thanks in advance!

2

No, and no. Roon can control the volume in software, but there’s no limit protection… a good reason to use a pre-amp, otherwise you may be looking for new speaker drivers. allo.com has some attenuator kits, or you can use a passive pre-amp.

2 Likes
3

A dac hat is a safer bet. Iqaudio hats work well with volume levels in Roon along with ropieee

4

I will agree with @mikeb, and strongly advise for a physical attenuator before plugging a source to a power amp. Never trust software volumes and default values, a simple bug may result to speaker destruction…

1 Like
5

They aren’t expensive these days

6

I also use a TC Level pilot X on my active speakers just to be on the safe side - but ropieee has been very reliable for the HAT based DACAMP’s

https://www.tcelectronic.com/catalog.html?catalog=Category&category=C-TCELECTRONIC-STUDIOCONTROLLERSANDMETERS-MONITORCONTROLLERS-PASSIVESTUDIOANDMONITORCONTROLLERS

I sit it on my desktop in easy reach. Might be only in XLR but you could use with a couple of adapters if need be fo anyone that needs RCA.

Highly recommended and looks great too…you might never want yr preamp back unless you actually need positive gain :slight_smile:

7

Thanks for your replies! The Allo Relay Attenuator is another card to stack, it’s still under software control, and it’s unclear if you need to use short RCA jumper cables between it and the Allo Boss or Katana or whatever.

I’m leaning towards the Orchard PecanPi streamer. I assume it sounds better than the HiFiBerry DAC+. It has XLR and RCA outputs; it has a physical volume control and I think I can use this in addition to software attenuation until I’m confident nothing will fry.

It seems that if I buy the PecanPi card and case without the Raspberry Pi it’s only $70 cheaper than the 4499 fully assembled price, but that way I can buy a top-of-the-line Raspberry Pi 4B that’s more future-proof than the RPi 3 B that I think it comes with. Hmmm.

8

4B runs hotter FYI

9

Just to follow up, I did buy an Orchard PecanPi streamer. It arrived promptly, I plugged it into Ethernet and connected its XLR outputs straight into my power amps, then powered it on. After a lonnnnng delay (as the puny setup instructions note) during which I guess RoPieee was updating, it showed up as a Roon endpoint and sounds great. It’s weird that it has no power-off button, but I eventually found the RoPieee web interface and its Advanced > [Shutdown] button.

I delved around in Roon setup and it seems to have great support for per-device maximum volume settings. So although the PecanPi Streamer’s physical volume knob is reassuring, I miss being able to control per-track volume from my Roon controller, and will probably disable the hardware knob (crosses fingers that there are no bugs…).