class d

People whose systems were built around conventional tube or SS designs expect magic just by inserting class D amps. Hell,that can't be expected no matter what component is replaced!

I am still working on extracting their magic, but they ain't half bad now. PS Audio GCA 250 (level 2 Underwood mod) and Wyred4Sound SX 250 monoblocks

The bottom line is you have to work with them. I know this, they are VERY cable sensitive.

I heard my W4S on a mega system Scaena Loudspeakers ($50K), dCS Scarlati 3 piece digital ($70K), Nordost Odin speaker cables ($36K) and Tek Line Reference power cords (@$3K). The owner of the system was floored, and he is using the VTL Sigfried.

I've owned CI Audio D200, NuForce Ref9.02SE V2, Bel Canto Ref1000.

They each have strengths and weaknesses. The NuForce sounded most natural to my ears (unlike the God awful earlier NuForce amps), but they did not double power as impedance is halved, and therefore the sound they produced on my speakers was unbalanced. Bass was a bit shy.

The Bel Canto had great bass and balanced sound, but the top end was hot and tizzy.

The CI Audio did just about everything right, but they sounded flat and sterile.

I just didn't connect with any of them.

Much of the bad depends on how the output or recontruction filter is designed and what kind of capacitor is used in it and the higher voltage electolytic caps.

Just as SS or tube, there are better designs and their are worse.

Using the B&O IEC modules as is and inexpensive components throughout is what will produce 'sterile' sound from these amps.

Better desinged class D amps like the Spectron who deisgn their own IECs and ourput filters etc, sound much better and naturally cost more.

Hi Coffeey, as I have written abundantly elsewhere about what I have like in switching amps. . . I'll cover some of my less memorable experiences.

Heard the little Flying Mole monoblocks 2 years ago at RMAF. . . fuzzy, sterile, and forgettable, except for being extremely small and cute and inexpensive under $1K per pair.

Red Dragon -- heard at same show. Far too dark sounding for my particular preference.

JRDG 201 monos -- they are and older and a somewhat minimalistic design. sweet but a little cool, without the kind of subtle microdynamics that I like, nor with the dynamics that I want. They also can run out of steam and become glassy on louder passages unless the speakers are very sensitive. I heard the same problems driving Maggie 3.6, Vienna Beethoven Grands, Vienna Mahlers.

JRDG 501. Still an older design. Yet, you won't have authority problems with these. . . lots of authority in fact. . . I heard them on the same systems where I heard the 201s. Like the 201s they did not draw me into the music. While I would not call them sterile by any means, they do sound a little 'cool'. Perhaps more suited for Jazz ensambles than for female vocals or classical. JRDG has recently introduced an external PFC device called PC1 for the 501 and 201. This is said to bridge the performance of these amps much closer to that of the Continuum 500 and 312 amps. . . but I have no direct experience with PC1 in this application.

Channel Island monos -- heard last year at RMAF. . . sorry do not remember what model. Very nimble, but once again a little cool, and even a little tippy. On the other hand, these may not have been broken in, and switching amps are total bears to burn in. . . 1000 hrs or more in many cases.

The statement above about ICEPower based amps being inherently inexpensive poor performers is not quite correct. The issue is rather of how these power conversion modules are used. the same modules can be used in extremely basic and low cost devices, or can become part of much more sophisticated products costing upwards of $30K. Same as with transistors or tubes, really. And being the application of Switching modules rather new, the first design attempts were a little experimental and only moderately successful.
G.