AES67 & Dante Audio

Summary

AES67 audio IS SMPTE ST 2110-30 — they are the same protocol. The lab’s PTP-synced network is already an AES67/Dante-ready infrastructure. Phase 1 implements a basic AES67 stream using GStreamer (24-bit/48kHz stereo over RTP multicast). Future expansion integrates real Dante hardware into the studio.

The existing Focusrite Scarlett 18i20 is USB-based, not Dante. Integration options range from a 500-600 Focusrite RedNet PCIeNX card (native 256-channel Dante/AES67). Long-term, the 18i20 could be replaced with a Dante-native interface like the RedNet A16R MkII (~$1,800).

Dante runs on the same PTP-clocked CRS326 1GbE ports. The CRS326 QoS configuration supports Dante natively: DSCP 46 (EF) for audio, DSCP 56 (CS7) for PTP.

Timeline

  • 2026-04-03: AES67 identified as same protocol as ST 2110-30. No separate implementation needed.
  • 2026-04-03: Dante/AES67 expansion phases documented with pricing.
  • 2026-04-03: GStreamer audio stream commands drafted for Phase 1.

Current State

No audio streams running yet. GStreamer sender/receiver commands are drafted. Focusrite 18i20 integration is a future expansion item.

Phase 1 audio stream spec:

  • Sender: Stream-PC (GStreamer, audiotestsrc → rtpL24pay)
  • Receiver: SERVER-PC (GStreamer, udpsrc → rtpL24depay)
  • Multicast: 239.1.0.1:5004
  • Format: L24/48000/2 (24-bit, 48kHz, stereo)

Key Decisions

  • 2026-04-03: GStreamer test tone for Phase 1 — proves the protocol without requiring Dante hardware.
  • 2026-04-03: Dante AVIO USB as entry point ($130) — cheapest way to get real Dante on the network.
  • 2026-04-03: Audio routed through motherboard Realtek to Focusrite after Sound Blaster removal — maintains existing audio workflow.

Experiments & Results

ExperimentStatusFindingSource
GStreamer AES67 audioPlanned1kHz sine → RTP multicastPhase 1 plan
Dante AVIO on CRS326Future (Phase C)Real Dante audio on PTP networkFuture expansion
RedNet PCIeNXFuture256-channel native AES67/2110-30Future expansion

Gotchas & Known Issues

  • Focusrite 18i20 is USB, not Dante — cannot directly participate in AES67/Dante network without a bridge adapter.
  • Dante uses its own DSCP values — must match CRS326 QoS config (EF for audio, CS7 for PTP, CS1 for low-priority).
  • GStreamer Windows audio capture — may need wasapisrc or directsoundsrc instead of audiotestsrc for real audio.

Open Questions

  • Does the Dante AVIO USB adapter work alongside the existing Focusrite USB connection on the same PC?
  • Can Dante Controller discover devices on the CRS326 without a dedicated Dante network switch?
  • Is there a latency difference between GStreamer AES67 and native Dante?

Signal Feed (2026-04-15)

  • NAB 2026: Blackmagic announced Fairlight Live, a free software audio mixer (public beta). Supports ST2110 audio natively, unlimited channels/busses (hardware-dependent), VST/AU plugin support. quentez2: “Since it does ST2110 it might even be directly compatible with Dante configured in AES67 mode.” Could serve as a free 2110 audio endpoint for lab testing before investing in Dante hardware. (source: r/livesound, https://reddit.com/r/livesound/comments/1skrn0l/)
  • Real-world Fairlight Live latency: ~9-10ms at 64 buffer (tested with Digiface Dante + QL5 A/D). Viable for broadcast, not for live reinforcement. Control surfaces at 3.8K/$8.2K. (source: r/livesound, Electrical_Carob_699, 6pts)

Signal Feed (2026-04-16)

  • Fairlight Live “unlimited buses” marketing corrected: actual cap is 512 total buses, confirmed by rsv_music (9pts) who found the bus counter in the UI immediately contradicts the claim. Plan accordingly for large-scale broadcast audio layouts. (source: r/livesound, https://reddit.com/r/livesound/comments/1skrn0l/)
  • Church broadcast community already uses DAWs for live mixing, so Fairlight Live has an existing user base. FatRufus (15pts): VST/AU plugin support is the real differentiator vs dedicated hardware consoles. (source: r/livesound, https://reddit.com/r/livesound/comments/1skrn0l/)

Sources