Even if a Devialet power amp is possible, and technically I think it is, I agree with @Damon that the current 'complete' design is the best solution. If one really wants/needs separate components the Benchmark AHB2 power amplifier is very good sounding and even cheap. Good starting point for a system with separate components.
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Devialetless!
Roon, ROCK/Audiolense XO/Music on NAS/EtherRegen/RoPieee/USPCB/ISORegen/USPCB/Sound Devices USBPre2/Tannoy GOLD 8
250 Pro CI, MicroRendu(1.4), Mutec MC-3+USB
Devialetless!
Roon, ROCK/Audiolense XO/Music on NAS/EtherRegen/RoPieee/USPCB/ISORegen/USPCB/Sound Devices USBPre2/Tannoy GOLD 8
250 Pro CI, MicroRendu(1.4), Mutec MC-3+USB