Jeff Rowland 501s and PC1s

Clavil, the fragment you quote from Jonathan Valin's article contains a very good description of the foreshortening of treble low level information which was relatively common on the previous generation ICEpower amplifiers. Others, like Chris Martens, have described the same phenomenon as treble harmonics being disconnected from the fundamental. It is also true that in my experience, the 201 monos tend to sound a little short of 'lung capacity' on power hungry speakers such as -- for example's sake -- the Maggies 3.6. . . hence the feel of a toy piano. Having said that, Valin is comparing a $4K entry level monoblock amp with extremely high end devices costing several times as much. . . the performance delta is not completely surprising. I suspect that if he had the opportunity of applying a PC1 to the 201s, his findings may have been subtly different. . . but there was no PC1 available at the time the article was written. . . or even published.
It is my impression that the application of pre-PS power rectification of one form or an other for ICEpower amps may be a valid methodology to address the harmonic and low level information shortfall of early such devices. Only future may tell. Guido

Hi Guido,

sorry my english is limited ... what do you mean with previous generation? are the ICE - power modules used now for the 201, 501 or 312 from a new generation?

I have definitevely the impression that the sound of the instruments becomes richer with th PC1.

Hi Clavil, ICEpower modules of 501 and 312 are the same ASP1000. 201 uses if I recall correctly the ASP500. These are -- relatively speaking -- current modules. By 'previous generation' I really meant previous generations of end user products. For example, the Continuum 500 can be considered a newer generation product than the 501 monos, because of the more sophisticated pre-PS power management, in spite of being designed around the same ASP1000 ICEpower modules. Similarly, the original BC R100 and the newer Mk.2 versions use the same ASP1000 modules as far as I know, but the Mk.2 has pre-PS power management that the original did not have. The PC1 devices is designed to bridge 102, 201, 501, and C250 products to current generation performance. It is worth pointing out that different manufacturers/engineers evolve their class D creations along different lines, applying different strategies towards similar musical goals, and all operate within the constraints dictated by their respective pricepoints. A priori, it is impossible to decide which approaches will be most successful, and in the end, only our own individual ears can determine what is most suitable for our own system and musical preferences. G.

I still had not the possibility to hear the PC1 with the original cables delivered by J.R
so that the PC1 are working with AET EVO power cords in
and adapted NBS Monitor II out

with / without PC1 makes a big difference, that even a sceptical audiophile friend had to recognize. It's such a difference that even non-audiophile persons would recognize it easily in a blind testing.

I agree with Phous:
- the stage imaging is becoming wider and deeper, the orchestra seems to stay some 10 subjective meters behind, as if you were sitting before in the first rows of a concerthall an then in the middle of the "Parterre"
I would add:
- the sound seems also to become richer & lushier

now my AET EVO & NBS II are probably also helping a lot ... ;-)

from the $ point of view, it is of course an expensive improvment as you have to buy the PC1 (here in Europe quite expensive) + 4 power cables (2 in + 2 out)

I talked to my dealer asking him why he didn't recommend to me to buy the Continuum 500, he said "if some day you want to change your loudspeakers, we have better possibility to tune the system with the diferent power cables precisely on your new loudspeakers. Nevertheless it would be very interesting to compare my combination with the Continuum 500.

Clavil said:
"I talked to my dealer asking him why he didn't recommend to me to buy the Continuum 500, he said "if some day you want to change your loudspeakers, we have better possibility to tune the system with the diferent power cables precisely on your new loudspeakers. Nevertheless it would be very interesting to compare my combination with the Continuum 500."

That sounds like an excuse to me. Selecting from the speakers that will match well with the Continuum 500 presents a very broad selection. The C500 can use any power cable. I would only agree with him if your speakers are very distant from the preamp.

Dave