Bob Carver 180 Mono-blocks perform superbly

Vicdamone, how does the NuForce Ref 9 sound compared to the Cherry 180? I have not had Class D amps in my system. I've heard them in other systems and at shows, but the sound never won me over.

So why are "vintage transformers" better than the ones wound now, specifically for these amps? Old is good?

Hi Ait, I did not say vintage transformers are better. For the eBay Cherry 180s, Bob used pie wound vintage transformers that he bought when he was in college, I believe. Pie winding was important in the old days when the "iron" wasn't as good as present day core material. In the pre-transistor era, transformer designers had to rely more on their winding technique than the core material to get good frequency response. But pie winding is more time consuming and difficult to do. This is what Bob told me.

Drac, well the difference is a lot like solid state and tube, so a comparison is not what I would call useful. When class D became recently popular there were some who wrote of hearing a tube like quality in the sound of their switching amp. I've had nine different switching amps in my system and none of them came close to sounding tube like.

My NuForce mono's began as the original Reference 9 SE and were upgraded to version 3. Generally speaking switching amplifiers are becoming more refined with the forward glassiness getting worked out. Channel Island, Nuforce, the big Rowlands, and the Hypex nCores to name a few.

I use switching amplifiers to power a pair of Avalon Acoustics Monitors in my studio. Their presentation that many find objectionable is exactly what I want from an amplifier in my studio environment.

I have used them in my main system but I prefer the relaxed presentation that only tubes provide for extended listening.

Switching amplifiers are simply a new amplifier option that many have found to meet their needs. The credibility and contempt by some in this hobby towards switching amplifiers is becoming more shortsighted. Design and technical improvements improve their sonic characteristics while maintaining their extraordinary efficiency and economical cost IMO.

I didn't know about the voltage differences in those tubes. Could that cause a problem? They were so inexpensive maybe I'll just forget about them.

Hi Vic, thanks for the description of sound of the NuForce.

I would contact Bob Carver, LLC and make sure those tubes won't cause a problem if you decide to directly plug them into your amp without rewiring.