Sunfire Sunfire Signature Series II

Hummmmm...It's been awhile for me with the BP3000's. But I do think I remeber them as being a bit more laid back than the BP2000's if I'm not mistaken. I could be wrong, but I've heard both several times, in many locations. I always thought the 2000's were better balanced. toward "alive" than the 3000's, which just had more bass output potentially. You might want to try a small monitor with more life in the same room to compare to your speakers if that's the case. Might be worth a look.
The Bryston is probably like the older Parasound amps in that it's probably a bit rolled off on top, and maybe warmish sounding...not agressive or analytical. What your speakers MIGHT need is a more foreward sounding and analytical amp...? It might not, I'm just thinking.
Yes, you could try the ATI amps, Krells, Older Acrus(if enough power), and other amps that border towards neutral to analyitical sounding. The balance could be tricky however, so you might have to tinker.
I wouldn't put it past the situation, as Sean mentioned to consider checking room accoustics and set up as well! Those Bipolar speakers can sound a bit too lifeless if you ABSORB the back wave of the speaker! Those are designed to integrate the reflections off the front wall back to the listen mostly. I've tinkered with the Def Tech's with using absorbtion for the front wall reflection points, and the results weren't as good as "reflection" or "diffusion" up front! That might be something to consider. Generally, the Def's are going to do better with more diffusion and life infront of the room than not I think. Also, if your room is, of course, too dead on top, that could hurt things. Acoustics is a strong "look-at" scenario indeed for you(as all).
Try one component change at a time none-the-less, otherwise you'll be lost!
Stay with it, and you'll find it.
good luck

I appreciate your response given the fact that you already owned a pair of Def.Tech.'s..I too had the BP2000's and up-graded to the 3000's, always thinking an upgrade will make all things better. Such as you know is not the case with my dilema. One poing that I think you contradicted yourself is:
"I've tinkered with the Def Tech's with using absorbtion for the front wall reflection points, and the results weren't as good as "reflection" or "diffusion" up front!" You said the same as up front twice, so which part do you mean ? I've been told that rear firing speakers don't play music as well as front firing (B&W's) so I've also put my Def.Tech.'s up for sale as I'm leaning more into music now. Please work with me here and clear up your paragraph above because I think you know my problem. Thanks again ! Larry

I’m a happy owner of two signature 600 amps and I can tell you with complete confidence that having two sig two’s vertically bi wired in your system is a ticket to musical bliss. But there is one little task that must be done to achieve this and that is isolating one plug or plugs to a ground rod outside the house to run your system and only your musical system. The day I did that both those amps just awakened for me and it was everything I ever wanted, clarity, giant soundstage and much more.  Try it and be rewarded with musical bliss.

Sunfire 600 signature owner here!

   Can not go wrong.

plus the series ~II is newer, used better parts, and is quite better than Carvers earlier sig amps.
it’s the one w removable power cord, plus the slightly different shape on the joul window meter.

 Those are rare, and demand a premium price, I searched for one for a while, before my Sunfire 600 sig was purchased for a good price.

 Please Send to Flannerys audio repair, the ONLY Rob carver authorized Sunfire guy, he is awesome, work is awesome, cleans the gear, new led for meter, replaces what needs to be replaced! 
  1000% worth a trip to Flannerys! Bought mine, had her sent to Flannerys, replaced many caps, and is great at talking on phone, telling you exactly what he did, and will answer all questions in a manner which you will understand!

I remember our conversations, he replaced a few things, new light, tested, re-tested, and made sure the amp was up to new specs.
   I was so happy on my report , apparently, if you drive this amp hard, there are some black color which builds up on some parts, and he can tell if the amp has been driven hard,.
“this amp has no residue, no blackening of anything, all parts are like new” he said, I was so happy, the amp is amazing and been flawless for many years now, and no, I do not drive too hard, it powers an old pair of BIC v830’s  plus a upgraded cerwin Vega D9’s. 
   YOUR series -II 600 Used better parts, and reviews on her are stellar, that is one of the greatest carver achievements/amplifiers to be made.
  The 600 was on the top list of the best amplifier achievements in the past 40 years. I would snatch her up, send to Flannerys, and enjoy a 20+ year audio affair.

  I read so much about the Sunfire 600 amps, and that 600 series - II WAS TOP DOG!

don’t wait, if it’s in great condition, get it. Plus the 2 taps, one has the 1 ohm resistor for a tube sound. I use them to biwire my energy rc-70’s when I feel like hauling the amp upstairs.

  Where did you say it is located for sale…😁🇺🇸🍻