Eight channels and four zones for installed Sonos systems
Sonos Amp Multi is an 8-channel multi-zone amplifier delivering 125 watts per channel into 8 ohms, with GaN Class D amplification for up to four zones, Ethernet, Wi-Fi 6, AirPlay 2 and fanless cooling.
This is the Sonos component made for professional installation: from a rack it drives passive speakers in several rooms, and each output can go to whichever zone needs it. Setup, channel tuning and status monitoring are handled in the Sonos app. It is an installed product: it must be fitted and configured by an installer.
Key features
- 8 amplified outputs, 125 watts per channel into 8 ohms with all channels driven
- Up to 4 zones; you choose the zone for every output, in mono or stereo
- Class D amplification with GaN transistors and post-filter feedback (PFFB)
- ProTune: parametric equalisation over 10 bands, gain and delay on every channel
- Stereo RCA line input and USB-C input for the Sonos Line-In Adapter
- RCA subwoofer output
- Apple AirPlay 2 and Spotify direct control
- Ethernet and Wi-Fi 6
- Fanless cooling
- Rack mounting with the 2U mount, sold separately
Zones and speakers
The eight outputs are set one by one, in mono or stereo, and shared out between zones to suit the system design, up to four zones per unit. With Sonos Architectural speakers the minimum load allowed is 2.67 ohms, and a dedicated optimisation can be switched on in the app: it recognises them and adjusts the signal processing to match. A Sonos subwoofer can be added to each zone; the RCA subwoofer output is assigned to one zone of your choice.
Amplification
The Class D output stages use gallium nitride (GaN) transistors and feedback taken after the output filter (PFFB). Stated figures: total harmonic distortion of 0.005%, frequency response from 15 Hz to 20 kHz within ±0.5 dB, signal-to-noise ratio of 114 dB, damping factor above 400 into 8 ohms. The chassis sheds heat without a fan; idle consumption is 5.4 watts.
Tuning with ProTune
ProTune matches each channel to the connected speaker and to the room. It includes parametric equalisation over 10 bands: for each one you set the gain (±15 dB), the width and the frequency, with bell or shelving filters; plus channel gain from −15 to +5 dB, a delay of up to 50 milliseconds and a high-pass filter between 15 and 100 Hz.
Sources and network
Amp Multi is controlled from the Sonos app and supports Apple AirPlay 2 and Spotify direct control. The stereo RCA input feeds an analogue source to one zone; the USB-C input, with the Sonos Line-In Adapter, makes it available in every zone at 44.1 kHz and 16 bit. It joins the network by Ethernet cable (100BASE-TX) or over Wi-Fi 6, on 2.4 or 5 GHz.
Installation
The unit measures 436.8 × 64.5 × 265.2 mm (width, height, depth), weighs 5.06 kg and comes in matt black. The 2U rack mount, sold separately, leaves room above and below for airflow and brings the width to 483 mm: no vent panels are needed between units. During setup each unit identifies itself in the app with a chirp; LEDs on the front and rear show the status of the unit, of the eight outputs and of the Ethernet port. The power supply is universal, from 100 to 240 volts.
Included accessories
Amp Multi comes with a 2-metre power cable and eight Sonos banana plugs. Speakers, speaker cables, the rack mount and the Line-In Adapter are sold separately.
