Thinking of buying a solid state amp

GLI, what sonic differences did you perceive between JRDG 312 and Pass X350.5?

Thanks, Guido

'd' just like any other topology has good and bad examples.
PF correction is used to help present a more resistive load to the power company. Large factories are penalized by the electric company when there PF drops below 0.9 or so, which is a moderate phase angle. I have measured my 40watt fluorescent tube at 0.8, when warmed up.

If such a circuit is presented B4 the amplifier, the amp's power supply need not be any different than without the PF correction circuit.

I have not yet measured my 'd' amp's PF, but will have data within a week. I suspect the PF to change as a function of load on the amp, but not sure in which direction it will go. I will be able to measure total draw, as well.

The Spectron amp is an animal. A very large number of smaller caps on each rail is featured in the power supply for lower resistance. Quite an amp, at least on paper. I'd like to hear it on my Maggies.

Guido,

We have spoken on the phone regarding your positive experience with the Rowland. Many thanks for taking the time to share your experience. I was waiting on a VAC for so long so I ended up taking the plunge.

The 312 has a crystalline transparent quality while being exceptionally coherent and smooth. Other switching amps I have previously owned includes the rowland 201, Nuforce 9se. The 312 is way better. The pass lab did not have quite have the same crystalline quality but displayed a richer tonal balance. In my previous system with Avalon Diamond speakers and ARC Ref 3, the pass was able to portray a wider tonal spectrum. The sound of the violin, viola, cello were more differentiated. The different horns were also more distinct. I tried the Rowland into my previous second system with quad 2805 and results are similar. When I played vinyl, the subtle differences between different instruments are lost and that is the deal breaker for me. An unexpected benefit from the Rowland was that background noise form the record is less apparent. I suspect that switching amps need filtering and during the implementation, something musical was lost or obscured. X350.5 and 312 are equally dynamic with 312 displaying tighter bass. Both lost out to the Boulder 1060 on bass and macrodynamics.

I really wanted to love the Rowland for efficiency, looks and long successful history of the company. Unlike some of the other posters, I have never had treble glare. It was just too smooth. I left it on for 6 month continuously with music playing most of the time and also tried different power cords.

I absolutely do not have great ears and yours are way more trained than mine. I took your advise and visited the Sounding Room with Rod at RMAF. It sounded better than thru my system. If others would attribute my less positive experience to lack of break in, synergy with preamp or speakers or lack of care in other areas, I can accept it. Different folks or different strokes.

How about Boulder or Moon 7 lots of power out from both

Tube pre with class "d". I have a custom built 12au7 based pre and a Hypex class "d". Been running the combo for about 18 months. I think it sounds extraordinarily great. Tight highs, tight deep bass, extreme detail but, believe it or not, it still has that "warm" tube sound. I have heard class d amps with ss pre's and I think the sound is thin and dry. It reminds me of the early days of cd players through solid state everything. That's why I went to a tube pre. Have tried a variety of ss amps through the years. Tried a Tripath based class "d" and it sounded fine, but the Hypex is, in my system, better. Channel Islands is Hypex based, very well reviewed. I built my power amp using the upgraded Hypex components. I have no plans to replace it.