I think the ADI-8 QS is still a great converter.
It even supports 4 reference levels at inputs and outputs: +24 dBu, +19 dBu, +13 dBu, +4.2 dBu.
The setting +4.2 dBu corresponds to consumer level with 12 dB headroom.
The converters are with 12/10 samples converter latency (AD/DA) @44.1 kHz still fast and compareable to e.g. UFX II/+.
The values for THD are partly on a similarly high level as for the new M-1610 Pro and ADI-2 Pro FS. The ADI-2 Pro has only for A/D better values ("by another decimal place").
From other products / threads we can read that different converter (AK vs ESS) deliver no other / better sound. Same well and transparent AD/DA conversion. Most important for such a product seems to be that all relevant components are well designed.
Advantages of more modern products might be more in the following areas:
- easier handling via display / browser
- possibility to adjust the reference level per port
And if it is of importance for you:
- even faster converters for direct monitoring or integration of external devices
- even higher SNR/DR (which is measurable but inaudible)
The successor of ADI-8 QS is M-1610 Pro. If you need more channels: M-32 Pro AD and M-32 Pro DA.
Both products support MADI (per SFP module) and AVB. They can be configured at either the display or via Browser (LAN).
BR Ramses - UFX III, 12Mic, XTC, ADI-2 Pro FS R BE, RayDAT, X10SRi-F, E5-1680v4, Win10Pro22H2, Cub14