Nuforce step up from Sunfire for B&W 803N?

It's only rated at 190/300wpc but obviously power isn't everything...
Jeffkad (Threads | Answers)

Doubling power as impedance halves is sometimes everything, especially when the speakers being mated have significant impedance dips and spikes. The N803 impedance dip to 2-3 ohms should be a concern.

This should be considered when matching speakers to the NuForce Ref9V2SE.

The Sunfire can put out a little more RMS power than the NuForce at 4 ohms, but since the Ref9V2SE can pass undistorted 650-watt power peaks the NuForce will actually sound louder when playing music. If you're playing a sustained note the Sunfire might do better, but most of the music I listen to has momentary loud peaks, which again, the NuForce would likely handle better.

As you dip the impedance then the NuForce gets even better as it is able to provide 1300 watts of short term power at 2 ohms and can even handle loads below 1 ohm. The bottom line is that when playing real-world music the Sunfire has no real advantage. Realistically, either amp will provide enough power for the 803N speakers but I have a feeling the Nuforce amps will sound better.

Also, the NuForce 9V2SE sounds great with a good tube preamplifier and that is how I'm using mine.

I auditioned the Ref9V2SE with speakers that are 8 ohm nominal, but have dips below 5 ohms.

Compared with amps that double power as impedance is halved, the NuForce amps produced unbalanced frequency response that was light in the bass, resulting in a tipped up sound.

Otherwise the NuForce amps sounded very good.

They are worth an audition. Just pay particular attention to tonal balance on the B&W speakers.

Thanks for responses so far. As I step up in the world of hi fi, clearly there is no perfect fit. I am very happy with the sound of my setup, but I've caught the bug and am now looking to make it even better if I can within my restrictions of low heat and smaller size amp chassis. I am trying to figure out what I would like to improve in the SQ, and one thing is the visceral impact of bass (organ, kettle drum, etc) and the sharpness of the "thwack". Hence my concern over power, although I've heard that the nuforce has great damping which also contributes to tight bass and may improve the areas I've mentioned above. I may want to smooth out and separate instruments some overly bright or dense recordings, although I'm splitting hairs here. In fact, this may be more a preamp issue, but I'm thinking the bass is an amp issue, no? Another thought is the Spectron. Still interested in Nuforce vs Sunfire opinions too though.