Sunfire Signature... what is this?

The needle goes nearly to the 500... 450+ for sure, but I read that there was an adjustment pot for the meter on a board in the amp. I have a Sunfire Cinema Grand (405x5) that has 6-amp MDQ-6 fuses on each channel, which also leads me to suspect this amp is not 600w/channel.

I wasn't sure how much difference I would hear, going from one Sunfire at 800w/ch to another at 1200w/ch (4-ohm speakers).

The lack of difference was what made me start wondering.

All the manuals I can find on-line show 15-amp AC input fuse for both the 300 and 600 watt Sunfire 2-ch amps. Since this is a '99 model, maybe the 1st generation was different. And maybe I should send it to Rita's, for a tune-up.

Hmm.. ok, the reason I bought the 600 is that I had a 200x5 (C-1000), and although I didn't hear anything "wrong" with it, when I got the Cinema Grand 400x5 hooked up, there was a definite improvement (I know, different technology). So, I went with the "if more is better, still more is more better" philosophy.

It does make sense that there would be a point of diminishing returns. The 10-amp input, as Almarg notes, seems under-rated for 2x600w channels, and my speakers are 4-ohm (magnepan), so *could* pull 1200 watts each, which the amp wouldn't be able to supply for very long.

I hardly ever crank up the volume *really* high, but I again, at moderate levels, I hear an improvement between the
300w/ch C-1000 and 800w/ch Cinema Grand (into 4-ohms). I don't detect an improvement between the 800w and 1200w Sunfires, and maybe that's not to be expected, at moderate volume levels.

The "SS" mentioned by Rpfef appears at the end of the serial number, another clue that this is a Sunfire Signature.

I think I will send the amp to Rita's, and if I still hear no difference when I get it back, I'll figure out what to do, then. I'll have over $2k in it by then, and probably can't recover all of that, but I could then re-sell it with a clear conscience.

Thanks for the input. Great forum.

Twilo, the manuals suggest that the current source is possibly better for planar and/or ribbon speakers, the voltage source for conventional cone-type drivers. For the magnepans, I prefer the current source. Some classical pieces will bring tears to your eyes, the sound is so poignant.

You can also bi-wire, if your speakers allow for it.

I think "best" would definitely depend on the speakers you're driving, and the material you're playing.

Grannyring, Bill at Carver's repair (formerly Rita's) did work on my Cinema Grand... the service isn't cheap, but it's worth every penny. That amp got damaged by lightning, Bill brought it back to life. Soon, he'll be getting a look at this sig-six.