Ohm Walsh Micro Talls: who's actually heard 'em?

TObe,

10K ohm input impedance may be fine for many tube pre-amps, but I would just note that there are some Class D amps designed to work well with any pre-amp, inlcuding tube, like Wyred4Sound and Bel Canto, that introduce 60Kohm or higher input impedance for that purpose for best results in all cases. 10K may sound fine but could be more hit or miss for best results in terms of dynamics and low distortion IMHO. The reason is that most impedance ratings including those for pre-amp outputs are nominal for all frequencies but actual impedance varies significantly by frequency, so my opinion is that a high amp input impedance is a good insurance policy in order to be safe.

BTW, I considered the older D-Sonic Icepower based amps at the time but ended up going with Bel Canto for significantly more cost. THe 10K input impedance rating of those older D-Sonics plus no special robust design for the Power supply to the IcePower module used were the main reasons. I use an ARC sp16 tube pre-amp. Who knows, maybe it would have worked out fine, butI have not regretted going the way I did. THe newer D-Sonics have more appeal for me, especially assuming the higher powered ones have 40K input impedance or higher. That is what I recall reading for Pascal Class D amp modules on the Pascal site, but not certain. Pascal amps also appeared to be stronger out of the box in terms of power supply, current delivery capabilities, and overall switching amp specs compared to older Icepower. Assuming those are what is used, I would expect the product to sound VERY good, at least if they live up to the specs on paper. Were I in the market for another amp today, the D-Sonics would be a much stronger contender than 2-3 years a go or so.

First question for me is what Class D amp modules D-Sonic uses now. Most of what I have read has been speculation

Reading info on Pascal site again, Pascal may not be the most impressive Class D amp out there on paper compared to other newcomers I have seen mentioned as possibilities for D-Sonics, especially for some tube or other higher output impedance pre-amps, but for the price are still certainly worth consideration in any case.

You are right but Wyred 4 Sound and other manufacturers include a buffer stage ahead of the Class D amp for the simple reasoning of increasing the input impedance, making it an easier match for tube preamps. I personally would prefer not to have the extra circuitry dressing and go all natural.

Mapman, your ARC SP16 tube preamp has a output impedance of 260 ohms. Using the simple rule of thumb that the input impedance of your amp should have at least 10 times or more, the output impedance of your preamp, 260 ohms * 10 = 2.6Kohm. At 10Kohm for the D-Sonic M2, your ARC tube preamp would have no problems whatsoever.