Pi with an off board USB DAC?

[David.WE.Roberts]

Has anyone tried using an off board DAC with the Pi?

I have just bought a Cambridge Audio DacMagic 100 which works well with
Windows, but seems to be just right to be linked to a Pi in the HiFi stack
to play networked music files.

A quick Google reveals very little about using DACs with Linux apart from
AvLinux.

I assume that most serious digital music playback uses the HDMI lead to an
AV receiver, but my AV receiver is still stone age and using SCART.

It can take digital in from optical or co-ax but not HDMI and AFAIK the Pi
doesn't have an S/PDIF port.

So - anyone tried it?

If so, how did it go?

Cheers

Dave R

[Rob Morley]

On 8 Aug 2014 10:29:04 GMT

"David.WE.Roberts" <nos...@nospam.net> wrote:

> Has anyone tried using an off board DAC with the Pi?
>
> I have just bought a Cambridge Audio DacMagic 100 which works well
> with Windows, but seems to be just right to be linked to a Pi in the
> HiFi stack to play networked music files.
>
> A quick Google reveals very little about using DACs with Linux apart
> from AvLinux.

It's a standard USB audio device, so it should "just work".
From the manual:
"For most builds of Linux with the DacMagic 100 switched to
USB Audio 1.0 the DacMagic 100 will work with the native
Audio 1.0 driver and accept audio up to 24-bit/96kHz.
Some very new builds of Linux are now supporting USB
Audio 2.0 for which the Dacmagic 100 should be switched
to Audio 2.0 support to accept audio up to 24-bit/192kHz."

And this says it's fully supported:
http://www.raspyfi.com/raspberry-pi-usb-dac-and-raspyfi-supported-dacs/

>
> I assume that most serious digital music playback uses the HDMI lead
> to an AV receiver, but my AV receiver is still stone age and using
> SCART.
>
> It can take digital in from optical or co-ax but not HDMI and AFAIK
> the Pi doesn't have an S/PDIF port.
>

You can get HDMI splitters that output S/PDIF for about £20 - as it's
digital to digital they likely sound OK (they have line level audio
output too, which obviously uses some sort of DAC so may not be great).

[Jasen Betts]

On 2014-08-08, David.WE.Roberts <nos...@nospam.net> wrote:
> Has anyone tried using an off board DAC with the Pi?

Only the one internal to my HDMI TV

> I have just bought a Cambridge Audio DacMagic 100 which works well with
> Windows, but seems to be just right to be linked to a Pi in the HiFi stack
> to play networked music files.

t says driverless on the website, I'm assuming that means it uses
some USB stabdard interface, HID or whatever the equivalent is for
audio, so it should work just fine with the pi.

--
umop apisdn

[David.WE.Roberts]

Thanks - very useful.

Switching the DacMagic to USB Audio 2.0 is something of a black art.

Once done by arcane button pressing and much cursing, it is recognised as
a different device by Windows and you can then install the Cambridge Audio
driver which seems to manage to keep it in USB Audio 2.0 from then on.

Note that until you manage to get it to switch modes you cannot install
the driver and thus you cannot upgrade the firmware. Not the best 'out of
the box' experience although support was prompt and good.

I suspect the challenge will to be to convince the Pi to use the 2.0
driver.

Anyway, looks promising.

Another Pi could be going on my birthday list.

Oh, and I am very wary of line level audio output - the DAC makes a huge
difference compared to 'line out' from various sources such as PC, phone,
tablet.

Cheers

Dave R

[Theo Markettos]

David.WE.Roberts <nos...@nospam.net> wrote:
> Has anyone tried using an off board DAC with the Pi?

Jim Lesurf over in uk.comp.os.linux has been doing lots of USB audio things
lately (on Linux and RISC OS). I think one of his test platforms is a Pi.

http://www.audiomisc.co.uk/index.html
has some articles (with spectrograms).

Theo