DEVIALET EXPERT PRO 220 INTEGRATED AMPLIFIER WITH THE SAM (SPEAKER ACTIVE MATCHING) SYSTEM.
“The expert Pro is one of the best amplifiers ever. Its technical performance is at the very highest level, with extremely low distortion, low noise, and extraordinarily flat response into loads. The amplifier uses a Class D circuit to rough out the output signal and a Class A analog amplifier to trim things to perfection. And effectively perfect they are. But what sets the Expert Pro into a realm above all others is the SAM system, wherein the performance parameters of your speakers, measured by Devialet, are downloaded (by the user) onto an SD card and then loaded into the Expert Pro At that point, the Expert Pro “knows” what electrical signal in the bass should be sent to the speakers to produce an acoustic replica of the Expert Pro’s input. It watches the speaker, checking it 86,000 times a second, and arranges things so that the speaker will reproduce the actual input. The result is better phase behavior (and hence better “timing”) and lowered distortion. Also the system tracks the dynamic envelope that the speaker can generate, and when response can be safely extended, it extends it. The results are all but uncanny. The superb but small Graham Audio LS5/9 suddenly sounded like a an equally good but much larger speaker, capable of a far more truthful picture of the bass of orchestral music, for example. Dynamic limits still existed, of course, but overall,not to put too fine a point on it, you have to hear this to believe it. And with larger speakers that already have something like full bass extension, there is, even so, much improvement in precision and consequent realism. The musical effect of what the SAM system does is very striking and very satisfying, as well. the SAM system is something new, and truly remarkable (Review forthcoming).”
Robert E. Greene
The Absolute Sound. 2019 Golden Ear Awards.