It's B-A-A-A-ACK, and in a good way!

[JohnnyB]

A couple (or so) years ago I called attention to a killer deal on a home audio power amp. It's a real "big boy" amp, with wide bandwidth, low noise, fast rise time (better clarity and articulation) and very decent power.

 

Once again, Audio Advisor has this NuForce 80wpc power amp on clearance--$1299 marked down to $417.99. (Pay attention to the enthusiastic user reviews.)

I have experience with these AA Clearance deals. They're on sale for having "used" status, but they are not returns from dissatisfied customers. Rather, they are brand new, unused components that were unboxed so they could be photographed for their catalogs and website, after which they were returned to their factory boxes and inventoried at Audio Advisor.

I personally scored a massive 5-channel Adcom home theater amp for $550 marked down from $1550 at least 15 years ago. At that price I assumed that it was a used and returned item. To my surprise on initial installation it sounded rubbery and indistinct, and gradually became cleaner and more dynamic-sounding as I let it run in for a few hours. In other words, it had not been played enough to break in, which means it had not been used. Fifteen years later this amp still anchors my 5-channel home theater system and is in use for hours day and night for TV, cinema, and violent, noisy video games. Definitely not a defective return.

This NuForce would also be an "unbox and click" catalog item. Full factory warranty and AA return policy are still in effect. It turns out that this amplifier is the result of a collaboration between Optoma and Goldmund. Goldmund is a high-end boutique brand based in Switzerland whose proprietary power amps sell in the 5-figure range. By comparison, $1299 is chump change and $417.99 is a steal.

Also, this Nuforce amp is a smooth, musical-sounding Class A/B design, produces 80 wpc, and yet weighs under 14 lbs, normally the weight range of a more abrupt-sounding Class D amp. My 100wpc A/AB amp weighs about 40 lbs.

Detailed (but wordy) review from a High End magazine here.

[Joe G]

I bought this amp from Audio Advisor a couple of years ago at $400, and returned it. The NuForce sounds great, but it did not match well with my Hafler preamplifier and I didn't want to replace that, too. The issue that caused me to return it was, an impedance mismatch between the preamp output and the amplifier input made it impossible to play the amp at low volume. With the volume set below 1 - at the first click and as low as it could go on the preamp, the MUSIC WAS LOUD, as if the volume was on 3 or 4. If not for this, I would have kept it. The volume issue is mentioned in online writeups about this amp.

In retrospect, to gain full control over the volume, I could have tried soldering resistors in line to the L and R channel interconnects to match the preamp out impedance to the NuForce high gain inputs. An easy fix for those who are handy with a soldering iron, but not what one expects to have to do when they purchase a new amp. For those who purchase this amp and don't run into the volume issue, it is a great deal.

 

[JohnnyB]

On 4/2/2020 at 11:58 PM, Joe G said:

I bought this amp from Audio Advisor a couple of years ago at $400, and returned it. The NuForce sounds great, but it did not match well with my Hafler preamplifier and I didn't want to replace that, too. The issue that caused me to return it was, an impedance mismatch between the preamp output and the amplifier input made it impossible to play the amp at low volume. With the volume set below 1 - at the first click and as low as it could go on the preamp, the MUSIC WAS LOUD, as if the volume was on 3 or 4. If not for this, I would have kept it. The volume issue is mentioned in online writeups about this amp.

In retrospect, to gain full control over the volume, I could have tried soldering resistors in line to the L and R channel interconnects to match the preamp out impedance to the NuForce high gain inputs. An easy fix for those who are handy with a soldering iron, but not what one expects to have to do when they purchase a new amp. For those who purchase this amp and don't run into the volume issue, it is a great deal.

 

The input resistance of the Nuforce  STA 200 power amp is 51kohms. I just read a test report of the Hafler Iris preamp, which measured an output impedance of 591 ohms, which is roughly 1/86th of the impedance of the power amp input.

 

[Joe G]

My preamp is the JF 200, which, except for silkscreening, is identical to this one here: https://www.worthpoint.com/worthopedia/rockford-fosgate-rf200-pre-amp-143057216

It's a biamping preamp that I bought new and used with kit amps that I built. 2 soundvalves tube 40 watt monoblocks up top, with a dynaco 410 for bass. Add in a Rotel cd player, Sony ES cassette deck, Denon Turntable and a Tandberg Tuner with custom built speakers, and that was my poor man's high end system of the 1990's.

Thanks for looking into that, and as always, JohnnyB is the Best!.