Stenho, so long as the DAC is not internal to the speaker I have not found any instance where the internal vibrations of the speaker have had a negative effect on the sound produced by the amplifiers. Many would argue micro-vibrations most seriously impact low-level signal amplification and my ear and years of experience with active speakers bears that out. The limitation I hear of active amplification have always been a case of additional D/A conversion, poorly designed DACs or DSP solutions or inferior amplification (mainly digital. Recording studios and engineers have long preferred active amplification) and felt audiophiles need not apply if they do not understand the benefits of placing the amplifiers at the voice coil provides.
I agree with Keith that most audiophiles prefer to mix and match their components and sonic signatures but would add many of us (myself included are still skeptical of DSP solutions, especially the lesser ones developed for the professional market.
A few notable new products are Avantgarde's iTron active amplification, DEQX newest DSP tri-band active amp solution preamplifier and Airplain of Switzerland newly released speakers utilizing Puri-Fi internal amplifiers built into stainless steel enclosures and a companion pre-amplifier with a complete Weiss digital engine as an external front-end. Legacy's Wavelet system, and also Linn and Meridian system that have been at the forefront of digital amplification for over a decade.
Finally, active systems will keep advancing and will continue to co-exist nicely with good old fashioned non-active two channel systems. A final example would be Kryon, featuring amplification and DSP outside the speakers and now using eight discrete channels of Halcro amplification. I heard their early solutions using first generation Hypex amplifiers and was impressed. Now some 10 years later I imagine these powered actively filtered dipoles are at the edge of the art.
Note, I have no commercial affiliation with any of the firms, just my ongoing curiosity for the ever advancing technology from my 10 years building custom active systems before founding Hear This.
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