Review: Sunfire Sunfire 300 Amplifier

Category: Amplifiers

For the past several years I have enjoyed my Definitive Technology BP 20s with first twin monoblocked Sumo Ploaris III amps (they would rate in the 450 Watt range under the Definitive 6 ohm load) and next with an older Spectral 100 WPC amplification. The Spectral product though by specification was vastly inferior blew the doors off of the Sumo products. Recently I had need to move my Spectral amp to another location. In this vacuum I inserted the Sunfire. I have never been more amazed! This amp again leaves the Sumos in the dust but keeps up with and in beats even the Spectral in some areas. It is nearly as fast as the Spectral far more musical and never ever under any strain clips or loses control. I have not reached the boundries of this amp. It never gets hot, looks great (wife likes it?!) and sounds great. It projects an amazingly deep, wide and tall sound stage far byond that of the Spectral. For this kind of money nothing I have ever heard aproaches it. Actually I have rarely heard far more expensive amps that compete. You cannot go wrong picking up a product like this from Bob Carver's Sunfire corporation! I have only one real complaint. The rear binding posts are plastic. I find this silly on a product of this caliber. As soon as I get a chance I plan to replace the crummy plastic posts with rugged metalic ones worthy of a really tight connection. (not one but 2 pair are required). Hope this helps!

Associated gear
Definitive Technology BP 20 speakers, Parasound HALO P3 preamp, MIT cables, and EAD CD-1000 front end.

Similar products
Sumo Andromeda, Spectral DMA-100
You are correct, the Sunfire does not run warm at all and has seemingly endless power.

I auditioned a number of amps trying to satisfy the difficult appetite of my Thiel 3.6s. I've had other Bob Carver amps and while competent they don't have the resolution to go with the grunt. The TFM-35 drove these speakers fine, but just didn't have the level of detail or clarity that the Sunfire has. Admittedly, I slightly prefer the sound of the Classe CA300 and Levinson amps with the Thiels; however the Sunfire comes very (very) close. I also have had slightly better bass control from the likes of a bridged Citation 5.1 but in that case the rest of the audio spectrum just wasn't as magical as it is with the Sunfire.

As you mentioned I'm not sure that I can do any better unless I spend a ton more money - even then the differences I've noticed are extremely minor. Thanks for the review.

Associated Equipment:
Thiel 3.6 Speakers
Sunfire 300 Amplifier
Musical Fidelity A3.2cr Preamplifier
Pioneer Elite PD-54 CD Player
Monster M550i Interconnects
Monster M1.2S Speaker Cable
As an owner of 6 300's used in a multi channel set up I can only agree with the op!!

Why no 600 for you ? 

I bought a 300 brand new In 1995. I still have it. Over the years I've picked up more second hand. 

The 3db more is not worth the premium the 600 commands. I can pick up a 300 for $500-$700 where when you do finally find a 600 for sale, it's usually $2k or more.

I have also read that the 600 sounds different then the 300.. I guess I just like the original recipe!! 

Good to know about the 600 v 300 . The 300 i have has the copper ? binding posts v the plastic . So i must have older model from what ive read . Definitely worth $300 to me to get it like new spec wise . Earlier you mentioned going inside the case to make mono ? I do not recall seeing that in the manual ? I recall the different ways of wiring on the posts though ?  Theoretically i could use 4 of these in a 2 channel setup ? My tweeters (5 per speaker) in my stats probably could use their own amp .

How do you use them with your Soundlabs ? Do Sounlabs have bass and tweeter taps even ? I recall someone stating they have no crossovers on another forum .

Yes, what I am having done is essentially the same as the manual, except internally. Tie the inputs and speaker outputs together. 

As as much as I admire Bob Carver, I don't think much of the current or voltage source set up.

If you look inside, you'll see a 1ohm resister on those outputs and that is supposed to give you a tube like sound..hmmm 

So, I'm going to strip all that extra junk off.. Have 1 set of speaker posts and 1 RCA jack.

That should make an improvement to the noise floor and clean up the rear of it. They won't be stock anymore, I always wondered why he didn't make a mono Sunfire..

Weird.. Maybe he was and never did because he sold the company.

My SoundLabs do not have dual binding posts. They do have separate low and high transformers. There are 3 dials on the plates of the Sl's for adjusting the low/mid/high's.

 They can eat a Ampflifier for a tasty snack should you try and push them hard. But these Sunfires can drive them to incredibly loud levels and still not get more then warm to the touch. 

Because I am using very expensive silver WBT Posts, I wouldn't want to buy another 4 pair anyway!

You could split them and power each transformer separately, but after talking to Dr. West, he said it wouldn't really make a difference.

Thats why I wanted to convert my 300's. Now I'll have a 1 channel 600 powering each speaker.

If this project works out with Bill Flannery, I may send him the other 4 to modify and maybe pick up amother pair of 300's and then I'll have 8 mono blocks to use in my 2.8.2 system.

I run (2) SoundLab A1's for L-R, (2) Sunfire CRS-3C's in a dual center channel, I have (1) Sunfire SRS-210R Subwoofer and will be adding another. And I am in the process of picking up (4) Sunfire CRM-2BIP for the side and rear surrounds.
I was fortunate enough to audition the sunfire 300 x2  with its matching tubed preamp driving a pair of B&W Nautilus 802 speakers, that system kicked audio ass my friends.