Confused by ICE applications

Icepower modules are complete amps, many of them with universal (90-240VAC) SMPS built in. As for usage by JRDG or Bel Canto - it depends on the price tag. The least expensive amps based on Icepower 200ASC (100/200W) just have addition of metal case and connectors - that's it (in case of Rowland's model 102 there is additional differential amp THAT1200 at the inputs). More expensive units like Rowland model 312 have even power isolation transformers built in.

B&O does not allow any mods to their Icepower units (voids warranty) but manufacturers like Rowland might do some mods anyway or order units with specific mods at their request. Until now Icepower was not selling modules to public, but recently Icepower was bought back by B&O (Karsten Nielsen left company) and now some vendors started selling them.

Damping factor at low frequencies is limited by the resistance of the inductor in series with the woofer to about 100. To avoid lowering it further an order better amp's DF is more than sufficient. At 20kHz similar limitation is placed by the speaker's cable inductance.

I don't think Onkyo uses an ICE module for its A-9555 class D integrated. Its damping factor spec is a mere 25, but you'd never know if from the sound in my rig. It's clean, tight, full, and extended. Anything but woofy or characterized by overhang. And I've been A-B'ing it with a VSP TransMOS 150, which has a damping factor around 1000.

In my rig, to the Onkyo's advantage (concerning damping factor) the woofers are a mere 5.5" in diameter, but to its challenge, one is augmented by a passive radiator and the other by a tuned port. Yet the bass is clean and totally tuneful.

Johnnyb53 - Onkyo is 85W and the smallest Icepower, as far as I know, is 100W/8ohm.

Damping factor is a little confusing. My Icepower has DF=4000 at low frequencies. Is it the reason for its tight bass? Atmasphere transformeless tube amps have DF=1.5 and very good sound.

Sometimes I get impression that sound is inversely proportional to specifications. Buying gear by good specifications is probably the biggest mistake.

As for small woofers - ask any bass player about bass rigs with good bass definition and he will tell you to look for stacks with a lot of 10" speakers. Larger 15" or 18" are also in use but have poor definition.

Few small speakers are far better than one large - just look at Dali Megaline design (perfect).

Amps with high damping factors can cause a reduction in perceived bass in speakers with limited low frequency capability. For example, when the midrange driver is also handling the lower frequencies.

The was an article at 6 Moons a while back discussing the optimum damping factor varying by speaker design.

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