HiFi DAC expansion module (Koha, concept)
Koha's proposed ES9039Q2M DAC card on the expansion slot's I²S: 3.5 mm and 4.4 mm balanced headphone outputs, line-in, OPA1612 amps, about $75 — still a design.
What it takes
- Plug & play
- Purchase required
Difficulty 1 of 3 — easy.
Details
Proposed in May 2025 for community feedback: an ESS ES9039Q2M DAC fed over I²S from the expansion slot, four OPA1612 op-amps giving 400 mW balanced (4.4 mm) or 200 mW single-ended (3.5 mm), a 3.5 mm line-in, 32-bit/384 kHz PCM, around −120 dB THD+N, a two-mode power switch with LEDs, and the internal speaker kept working. Target price $75. Follow-ups considered an internal USB-A port for storage, dropped 6.35 mm jacks for lack of space and pushed recording to a possible 'uRecord' variant; MIDI over 3.5 mm adapters is not covered.
Tomhet's 2023 thread is the earlier version of the idea — a USB DAC/ADC card with four 3.5 mm ports and GPIO MIDI — which drew a long parts discussion (Pisound, WM8960, CS4271) but no board. Neither has shipped.