Audio Science Review of Expert 200.

[Confused]

Given Experts design topology, how can any of these measurements separate DAC performance from amplifier performance?

This is an excellent point, definitively they cannot. 

Consider you are measuring a "conventional" integrated amplifier, here you can measure just the amplifier, but to get measurements directly comparable to a digitally fed Devialet, you would need to add a DAC, which presumably adds its own noise, distortion and whatever else.

Indeed, in the case of the ASR measurements, or other measurements made via the analogue input, you are inevitably adding any noise or distortions from the ADC, which most of us do not need to use.  Clearly this penalises the Devialet results if considered in direct comparison with a conventional amplifier.

I suppose you could make direct comparisons of the digital input with integrated amps like the Gryphon or Hegal, which include their own DACs, but essentially these are just amp and DAC in the same box, a little different to Devialets ADH where the DAC is integral to the amplifiers performance.

A further step beyond all this is that with the typical usage for many, the Devialet is also a source as AIR or the CI board is effectively a "networked attached end point".

I do find the measurements interesting though.  As an example, I know many Devialet users get excellent subjective results using an external phono stage, which is fair enough when you consider that the built in phono stage is audibly noisy with low output MC's.  However, seeing how the various inputs measure, an external digital phono stage with S/PDIF output might be even better.  In theory at least.  It might even be possible to use a conventional analogue phono stage with an external ADC, which might yield good results if the external ADC measures better than Devialet's internal offering.  Again, in theory at least.

As an aside, I'm using the "listening with ears" method this morning.  No issues detected so far …….