Bob Carver LLC Black Beauty Review

I saw his amp's at CES, and I'm curious as to whether there's a sonic difference between his attenuators set at half volume vs. wide open, ie. resistive element out of the circuit. At one time ARC had a few attenuators on their stereo D115mkII amp and I noticed there were sonic differences depending on the position of the attenuator.

I bought a pair of these but had them fitted with KT-88s from Valve Art instead of the standard KT-120s (but not the cherry 180 chassis, these are 305s). The sound is precise, dynamic, and 'tweak-able'. I like the ability to switch feedback from "tubey" to modern with the toggle switch (I keep it on the tube side most of the time). Mine are black, though I understand you can order them in cherry red as well. I keep the bias at 70, not at a 100 as the reviewer in hotheaterreview.com did. It sounds more mellow. And I guess that is something I like about Carver's designs. He wants you to be able to adjust the amp to your liking, though that is seen as verboten by some. As to the price, well - they are expensive by any standards, but worth it to me. They may be the last amps I ever buy, not sure I will ever need more power or flexibility. Looking forward to winter, when I will use them to warm up the house.

I have a pair of the Cherry 180s, bought when Bob used to sell them on eBay. Mine was built with some modifications...V-Cap output coupling caps, Furutech RCAs, Vampire copper binding posts, and non-captive cords. It also has the vintage pie wound transformers, different than what is currently used. So mine should sound different the current production Cherry 180s. In my system, this is a great amplifier.

For comparison, I have the Atma-Sphere M60s with V-Cap copper Teflon coupling caps, Caddock resistor package upgrade, and power supply boost. The only thing M60s does better than the Cherry 180s is in the treble, it is smoother and more extended. I guess the OTL design is responsible for this. However, Cherry 180 has better soundstaging, imaging, macrodynamics, and bass extension. In fact, the dynamics and bass extension can be startling. Microdyanmics are similar for both amps. I know the M60 only puts out only 60 watts, but I'm not over driving them in my system, and play my speakers to similar volume levels when comparing the two amps. At high volumes, the Cherrys just runs circles around the M60s as it should given the difference in power rating. The Cherrys are the quietest tube amp I have ever heard, equaling the best SS amps in this regard. No tube hiss even with your ear right up against the speaker. No transformer hum, unless you put your ear right on the transformer can. Jet black background when the music is playing.

The sweet spot is with the Cherry 180s, not the Black Beauties. They won't clip until about 240 watts, which isn't that far off from 300 watts. And the Cherrys are a lot less in price. The fact that you can use KT88s with the Black Beauties suggests the circuitry between the two amps isn't that different. I like the KT88 because there are so many brands out there to try. With KT120s, you're stuck with one brand.

The Cherrys are very versatile in that you can tweak the bias and feedback to make it gel with your system the way you want it. I prefer bias setting around 100 to 110 mA and feedback at vintage setting(~20 dB feedback). And, it can drive the Apogee Scintilla, as it was designed to. How many tube amps do you know under $10K, or over, that can drive 1 ohm impedance of the Scintilla? This amp can cover all genre of music.

This amp has potential to become one of the greats in audio, an amp to hold onto for the rest of your life. The thing that holds it back, IMHO, is the parts quality of the amp. Some of the parts in the stock amp are...well surprisingly pedestrian and should not be in an amp in this price range. Just couple of simple tweaks (eg, changing output coupling caps, ditching the stock volume pot by going direct or replacing it with stepped resistor attenuator, etc) will do wonders.

I agree with Teajay in that Bob's amp sound lies somewhere between ARC and CJ and can be tweaked to approach either side of the spectrum.

@Dracule - agree with your perspective. The difference between 240 and 305 is relatively small, but could be useful in some cases. The Cherry and the Black Beautys look very similar - same size etc. - the only difference I surmise is the power supply that is able to handle the KT-120s demands.

I am interested in the upgrades you mention - the V-caps and stepped resistor attenuator. Will ask about them (CarverFest is coming up next week so I am sure thee will be a lot of discussion about tweaks for the 305).

If you have efficient speakers the Black Magic may be the way to go. Amazing little amp for the money.

"....If you have efficient speakers the Black Magic may be the way to go. Amazing little amp for the money...."

After hours at Capital Audio Fest we put the 20 watt Black Magic into the system (Purity Audio Design Statement preamp, Daedalus Audio Athena speakers and AMR front end) and this little amps sounded pretty darn good considering it was not broken in at all. The Athena's are about 97dB and while you're not going to rattle the windows, the 20 watts did a fine job of driving them.