Mandarin DAC Bridge

Output: the Bridge, over UPnP

Settings → Audio → choose "<DAC> (Bridge)" in the UPnP list, not the DAC itself. While Audirvana still holds the DAC directly, its tile on the bridge's page says Waiting · Audirvana has the DAC. The bridge takes the DAC the moment Audirvana lets go of it.

A zone like any renderer

Settings → Audio Devices → choose "<DAC> (Bridge)". If Mandarin's own local output for that DAC is switched on, switch it off: the bridge owns the DAC now. Mandarin's volume sets the DAC's own, where it has one (Volume).

Lyrion Music Server, and Roon

Switch on Squeezebox under Connections on the bridge's page. Each DAC then becomes a player, "<DAC> (Bridge)", for Lyrion Music Server (LMS) — and for Roon, with Settings → Setup → Squeezebox support on. The bridge speaks the Squeezebox protocol itself rather than running squeezelite, because squeezelite would need the DAC to itself. The server is found by itself; type its address if it isn't.

FLAC, PCM, AIFF, MP3 and Ogg are taken as they come, gapless. DSD is converted by the server. LMS's volume sets the DAC's own, where it has one; for a DAC feeding an amplifier, set the player's volume control in LMS to fixed at 100%.

Through Spotify Soloist

Spotify Soloist is Spotify's own Spotify Connect client for Linux. Switch on Spotify Connect on the bridge's page and each DAC appears in the Spotify app's device list. It needs:

· Your own Soloist API key, made at Spotify for Developers (needs Premium), typed on the page. It is never shown again.
· Soloist, which may not be passed around: Download Soloist on the page fetches Spotify's own build for the machine. A build lasts 90 days; the page shows until when.
· Linux with glibc 2.38 or later (Debian 13, Ubuntu 24.04, Raspberry Pi OS trixie), or the Docker image on anything older. There is no Soloist for macOS.
· PulseAudio (sudo apt install pulseaudio; in the Docker image already).

Soloist plays into a private PulseAudio with no sound card, only a pipe the bridge reads, so its sound takes the same exclusive path as everything else, at 44.1 kHz, paced by the DAC: nothing is resampled. If another app has the DAC, Spotify is paused. Spotify's volume sets the DAC's own, where it has one; otherwise it stays at 100%.

Soloist takes the key only on its command line, so other accounts on the same machine could read it from the process list; on a machine you share, run the bridge in Docker. On a Mac, the Spotify app itself plays through the bridge instead (below).

Through QobuzProxy

Switch on Qobuz Connect on the bridge's page, press Install QobuzProxy (it fetches QobuzProxy into a private Python environment; Python 3.10 or later must be on the machine, and is in the Docker image), then Sign in to Qobuz on QobuzProxy's own page. Each DAC then appears in the Qobuz app's device list, as "<DAC> (Bridge)".

QobuzProxy speaks Qobuz Connect and hands each track to the DAC's UPnP device, so Qobuz plays through the bridge like Audirvana does, in hi-res up to the DAC's best rate, under the same one-app-at-a-time rule.

Through Caldera Headless

Switch on Plex · Caldera Headless on the bridge's page, press Download Caldera (from Caldera), then Sign in to Plex: the page shows a code to enter at plex.tv/link. Each DAC then appears as a player in Plexamp, Plex for iOS and the Plex web app.

Caldera plays to the DAC itself, bit-perfect. The bridge shares the DAC with it: whoever plays first has it, and the other waits. What Caldera plays shows on the DAC's page and on the now-playing screen.

The Music and Spotify apps, bit-perfect

Neither app can play to a DAC the bridge holds, or switch its rate per track. So, as Arco does for Roon, a small virtual output, DAC Bridge, is the Mac's output while this is on: the app plays to it, and the bridge plays the same samples to the DAC you choose, at each track's own rate (Spotify at 44.1 kHz), with the virtual output's clock following the DAC's. Install the output once (your password; the Mac's sound stops for a few seconds):

/bin/bash -c "$(curl -fsSL https://raw.githubusercontent.com/meltface-80/Mandarin-DAC-Bridge/main/tools/mac/driver.sh)"
# remove it again:  … driver.sh)" -- --remove

Needs Apple's command line tools (it offers to install them). Then switch on This Mac: Apple Music & Spotify on the bridge's page. The first time, macOS asks to allow Microphone access: that is how the bridge reads the DAC Bridge output (it never listens to a microphone). Switched off, the Mac's output goes back to what it was.

New: on a test Mac the DAC Bridge output gives back what it gets, sample for sample, at 44.1, 96 and 192 kHz. Playing from the Music and Spotify apps themselves hasn't been tried on a real Mac yet.

Downloaded from Roon Labs, run beside the bridge

Switch on Roon Bridge under Connections and press Download Roon Bridge. Like RoPieee, the bridge fetches Roon's own build from Roon Labs. On Linux and in Docker it's unpacked, checked with Roon's own check, and run by the bridge (no root, no system service; it updates itself). On a Mac the app goes into your own Applications folder (~/Applications) and is opened; on Windows Roon's installer opens. Then in Roon: Settings → Audio, and enable the DACs under this machine's name.

Roon Bridge plays to the DACs itself, so while it's on the bridge lets go of each DAC whenever nothing plays through it, and takes it back when an app plays to the bridge (once Roon has let go). A Roon Bridge installed separately is used as it is. Or skip Roon Bridge: Roon's Squeezebox support plays to the bridge directly, with Roon's Squeezebox limits.

Roon now playing: switch it on under Connections, then enable Mandarin DAC Bridge in Roon (Settings → Extensions). The pages and the now-playing screen then show the title, artist, album and cover of what Roon plays to each DAC, through Roon Bridge or the Squeezebox player, from Roon's own extension API.

A monitor beside the DAC

Open http://<machine>:55500/now full-screen on any screen: cover, title, artist, album, time and format of what's playing, from any app, and a clock when nothing is. It follows whichever DAC is playing, or one you pick (move the mouse). On a Linux machine with a monitor plugged in and no desktop, this sets it up to start at boot:

/bin/bash -c "$(curl -fsSL https://raw.githubusercontent.com/meltface-80/Mandarin-DAC-Bridge/main/tools/linux/display.sh)"
# the bridge on another machine:  … display.sh)" -- --url http://192.168.1.20:55500/now
# remove it again:                 … display.sh)" -- --uninstall

Another app has the DAC

The page names the app. Point it at the bridge's UPnP device instead, or quit it; the bridge takes the DAC within two seconds.

Discovery can't get through

The bridge and the apps must be on the same network. On a Mac, allow mandarin-dac-bridge under System Settings → Privacy & Security → Local Network. In Docker, use --network host. On a machine with several networks, set BRIDGE_IP.

The other app is playing

That's the bridge keeping the apps apart. Stop the one playing (it keeps the DAC 10 seconds), or press Release on the DAC's page.

The container can't see /dev/snd

Check cat /proc/asound/cards on the host lists the DAC, and that the command still has both -v /dev/snd:/dev/snd and --device-cgroup-rule 'c 116:* rmw'. docker exec mandarin-dac-bridge /app/mandarin-dac-bridge --diagnose shows what the container sees.

macOS isn't letting the bridge read DAC Bridge

Allow mandarin-dac-bridge under System Settings → Privacy & Security → Microphone. Check that the Mac's sound output is DAC Bridge. mandarin-dac-bridge --loopback-test checks the output gives back exactly what it gets.