Confused by ICE applications

Damping factor is not a ICEPower characteristic per se. There's been a lot of discussion of DF in other threads. DF is only one of a series of things to consider when matching a speaker and amp and maximizing the amp's ability to control the speaker's drivers. Some speakers need a lot of damping and others do not.

He's not going to tell you exactly what he does, but Rowland does a lot of things beside add Power Factor Correction to his latest amps (Continuum 500 and 312). He does enough that representatives from B&O have a hard time recognizing their ICEPower units. What matters is how well it works. Listen and hear for yourself.

Dave

He's done a lot more with the 312 and Continuum, I'm told, but I haven't looked inside myself.

Dave

Yeah, the 102, 201, 501 and Capri are out of a single billet of aluminum, with all the attaching points machinced in to .003" tolerance. They're incredible. The face plates on the 312 and Continuum are single billets, the sides and backs are billet also, but "only" about 1/4" thick. Rowland was the first with this and now others are copying, even using the same supplier that he pioneered with.

Dave

Macdonj, on the 312 and Continuum 500 one huge difference is the addition of Power Factor Correction. ICE and D can really spike the mains and cause harmonic currents that can be audible. The PFC presents a more sinewave-like load to the mains and eliminates the harmonic currents. Additionally, the PFC converts AC to 385 volt DC, giving ample, clean power to the unit. The DC operation also helps with quietness of the pre-amp stage, approaching battery power style low noise levels. (PFC can be added to most current JRDG products with his PC1 unit).

Add to that, dual-mono, fully balanced operation for the Continuum, short signal path lengths, heavy aluminum billet chassis, internal and external isolation from EMI and RFI and you end up with a total package that's beyond most of the competition. Jeff pays attention to each wire, trying different materials to arrive at what he considers the truest (most transparent) sound.

Jeff's chassis alone adds significantly to cost (even on the lower level 102, 201, 501 and Capri), but they aren't just things of beauty. They're functional parts of the RFI/EMI control scheme. With ICE and Class D this is very important because of all the energy given off by the unit itself. Combine that with a nearby CDP and it gets very important. My Continuum 500 and Playback Designs MPS-5 CDP are right next to each other in a tight armoire, with a gaggle of wires cramed in behind them. Despite all that potential, the system is almost dead quiet.

Jeff creates very elegant designs. Look inside his Capri preamp and you'll be amazed at how view circuits there are how clean things are. His phono modules are the size of the last joint of my little finger, yet they compete with Levinson, Sutherland, Manley, etc. for resolving capacity. The phono circuit is utterly quiet in my setup.

Clean and simple is a core philosphy to Jeff. He lives by that and it pays off in the results.

Dave

In fact, on the Continuum the large flat surfaces of the chassis are ridged, to refract sound waves in those cases where it might be close to speakers. The tolerances on the Rowland chassis are .003". The nibs and screw threads for mounting boards, etc. are machined in, to the same tolerance. Like I said before, the Rowland chassis is no mere cosmetic design exercise, even though he highly values esthetic appeal.

Dave

I haven't heard the DarTZeel equipment yet, but I'm very confident that it's stunning; given the reviews I've seen from trusted sources.

However, it's interesting to compare DarTZ and Rowland to see that there's more than one way to skin an audio cat. Inside the DarTZ pre-amp there's a whole infantry of cards lined up, filling a relatively large case. In the amazing Rowland Capri preamp there's almost nothing, with phono cards about the size of the last joint of my little finger. Both work, apparently very well, but the design approaches are worlds apart.

BTW, the Rowland is designed by one guy and, I suspect, the same is true with DarTZeel. I know for fact that Rowland feel very strongly that his approach is "right" and I suspect that the DarTZ designer feels the same way.

Dave

Audiobb, do you mean a raw modules on which to build your own amplifier? If so, I think that you need to be a builder, but B&O is the source, or the ICEPower division of B&O. Do a little Google or Yahoo search and you'll find them. I don't think that they license others to sell just the raw units, but I'm not certain.

Dave

Ric Shultz was making some ICEPower amps and I believe that he stopped. Maybe he'll sell you an module or two if he has any left, or he can give you leads on where to find them.

Dave