Sherbourn Audio PA7-350

Selling a "kind-of" new PA7-350. To be clear, I purchased this new from Sherbourn years back for a dedicated home theater I was building. Shortly after, I had an injury and had to put the project on hold. The amp sat in its sealed box until getting the theater completed a couple months back. After connecting the PA7-350, I unfortunately came to the conclusion that with my theater processor having a higher impedance output and my speakers being a high 92-db sensitivity, the amp just wasn't a good fit. This amp is also rated to have 29 db of gain which is 3 db more than most amps rated at 26 db which only highlighted the situation. All of these details combined allowed for a slight hiss that I could hear from my sitting position. It wasn't terrible but I just didn't want to leave it that way so I bought another amp. Connecting a different preamp and speaker proved that the amp does not have excessive hiss so I just cannot use it with this setup. I hate to see this go as it does sound incredible. It's also probably way overkill for me having 550 watts available for all of my 4-ohm speakers.

The amp probably has no more than 40 or 50 hours on it from testing a couple hours each evening. It also feels cool to the touch with almost no heat what-so-ever, even after 3 or 4 hours of straight use.

The amp is in perfect condition aside from a small mark I putt on the top when I dropped an XLR connector on it. It's toward the back and hardly noticeable without direct light shining on it. It will be packaged and shipped as it was new in the factory double box. It is heavy at about 114 lbs. so plan on having help to get it in the house.


Specifications

The 7-350 is a fully discrete, dual differential, high current Class A/B amplifier that utilizes a SoftSwitch Optimized, Class-H power supply inside. Now, there is much to do over an amplifier’s Class among enthusiasts. Audiophiles tend to like Class A designs, whereas most home theater amplifiers utilize a Class A/B methodology. In recent years Class D has come into vogue. Class H isn’t “new” though admittedly it’s not as prevalent as the before mentioned options. While Class H is different, it’s not wholly unlike A/B -it’s just a little more efficient. At the end of the day, a properly implemented A/B and H design shouldn’t sound too different from one another, so don’t get hung up on the 7-350 or any amplifier’s Class designation. That being said, the 7-350 possesses a 3.3kVA toroidal power transformer inside with 180,000 uF storage capacitance. What is more important is the 7-350′s stated power output, which in this case is a healthy 350 Watts per channel into 8 Ohms and 550 Watts per channel into 4 Ohms. That’s a lot of horsepower, and for some it might seem like too much.

With regards to the 7-350′s distortion, it is incredibly low -less than .02 percent. Signal to noise is reported to be 76dB at 1 Watt (A-weighted) and 100dB at rated power (again A-weighted). The 7-350′s reported frequency response is 20Hz to 80kHz (+/- 2dB). Input sensitivity is rated at 1.7 Volts and gain at 32dB.

Includes:

Everything as new. Amp, Double Box, 20-Amp Power Cord, Instructions, Rack Ears