Innuos PhoenixI2S Board

Output Module for STREAM3, ZEN Next-Gen, and ZENith Next-Gen

I2S is the interface DAC designers prefer. Where USB and S/PDIF require the DAC to receive a serial stream and decode it — adding a digital receiver stage with its own noise and jitter contributions — I2S sends clock and data separately, directly to the DAC chip. No receiver. No reconstruction. The DAC sees the cleanest possible input at the lowest possible jitter. The PhoenixI2S Board delivers that interface from inside your Innuos chassis, via HDMI.

The Clocking

A 3ppb 24MHz main clock runs directly on the board, mounted adjacent to the USB chip so no precision is lost through cabling. Two additional FemtoClocks are dedicated to the audio path. FemtoClocks represent some of the most capable oscillator technology available for audio applications. When you're feeding data directly to the DAC chip via I2S, the clock you send is the clock the chip uses — there's no reclocking on the DAC side to compensate for errors. The clocking architecture here reflects that reality.

DAC Compatibility

Eight HDMI pin configurations are supported, covering the I2S implementations used by PS Audio, Denafrips, Gustard, Matrix, and other manufacturers. I2S pinouts are not standardized — eight configurations cover the most common arrangements, but confirm your DAC's pinout before purchasing. We can help you check.

Resolution

PCM up to 32bit/768kHz. Native DSD up to DSD1024 — the highest resolution the format reaches. I2S via HDMI is the only interface capable of carrying DSD1024. If your DAC supports it and you want to hear what it actually sounds like, this is the path.

Press Recognition

The Innuos PhoenixI2S Board has been discussed in reviews of the STREAM3 and ZEN Next-Gen by Hi-Fi+ and Hifi News, where it was cited as a meaningful upgrade over the standard USB output for DACs with well-implemented I2S inputs. The improvement is system-dependent — most significant when paired with a DAC designed around I2S as the primary interface.

Specifications

• Interface: I2S via HDMI connector
• Main clock: 3ppb 24MHz OCXO, board-mounted
• Audio clocks: Two dedicated FemtoClocks
• HDMI pin configurations: 8
• PCM support: Up to 32bit/768kHz
• DSD support: Native DSD up to DSD1024
• Power: Independent supply stage within host chassis
• Compatible: STREAM3, ZEN Next-Gen, ZENith Next-Gen
• Not compatible: STREAM1
• Installation: Factory-fitted or retrofitted

Not sure your DAC's I2S pinout matches one of the eight configurations? Send us the spec sheet and we'll check before you order.