Sunfire signature 600 help

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Apr 15, 2023
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Hello to all, I recently purchased 2 Sunfire signature 600's on audiogon. These are the first generation with the attached power cord and 19" version. I must say that this is the first amplifier in a long time that I could hear a significant difference. They are replacing 2 threshold statis 2 amplifiers that were driving my prodigy's. Does anyone know of a reputable shop or individual on the east coast? Preferably south east since I'm in Fort Lauderdale FL. I have used Bill Flannery in the past but he is no longer in business. Also I have searched for a schematic online but have failed. Any suggestions or help will be greatly appreciated. Thanks Tom
There are schematics on "the Carver site" ( for some of the boards used in the Sunfire amplifiers; however, the info is spotty and not easy to follow. Still, it is better than nothing. I have never found any other source of Sunfire schematics on the web. Sorry, I don't know of anyone on the east coast who can work on Sunfire gear. With Flannery out of business, the only place I know of is Nelion Audio (, Greg Garska CEO. However, I believe he is in Michigan. I have had good luck with Nelion, they did an excellent job of refurbing my early model Sunfire 600.
Great, thanks for the reply and the information. The more is listen to the Sunfire amplifiers the more I love them. How long ago was your refurb done? Did you notice a major improvement? Thanks again Tom
Tom, my refurb was done in 2020. I don't recall hearing a major improvement, he had the amp for about 3 months so it was a bit difficult for me to compare before and after given such a long time away. The major reason you want to refurb old Sunfire amps is to avoid a major failure. I had a 300x2 amp that self destructed and was impossible to repair because of damage to the circuit board. There are parts on these amps that are known to fail (like caps) that need to be replaced. Given the complexity of the amps and the lack of publicly available of schematics, it is hard for a private individual to do it themselves.

Bill Flannery and Rita's in Washington State were at one time the only places that were doing these kind of refurbs but they are both out of business now. I don't think there are any others except for Nelion although I have not searched recently.

Good morning Keith, I spoke with Greg at Nelion audio and decided to go with them. Their reviews are first rate. I will be sending my signature 600's to him in june. My only dilemma is if I want to send both at the same time which more that likely is what I will be doing. There is another shop Hi Tech audio in Oregon that Bill Flannery recommended on his voice mail. I really appreciate all your help and advice. Thanks Tom