Seems ironic that Sunfire amps once may have had a reputation for being reliable workhorses. I can't find the full review on the web now, but I believe Paul Seydor of The Absolute Sound may have made that point when writing about the Sunfire Architect's Choice Series II amp. He had heard of Sunfire amps in commercial applications (driving shaker couches or the like), running for years without a hitch.
https://www.enjoythemusic.com/tas/139/ (table of contents only)
I picked up a Sunfire Cinema Seven for really cheap on Craigslist, but I would be afraid to open it up after seeing these pictures! (Might need the seven-hand facepalm.)
They run very very cool due to efficient power management.. So the components are not stressed thermally at all. You can leave the thing on all the time and it uses less or around the same amount of electricity most acts do in standby mode.
In fact, the greatest wear on components is likely at inrush: on powering up house lights dim on a brand new 15amp circuit and there is no soft start on the thing. Those 18000 if caps rated for 150v and the huge transformer are thirsty at startup. After that current draw is very low typically.
The one I had is around 30 years old and was used heavily by my father especially; in its first 20 years. It was transported xross country in three moves, etc. and endured some wild voltage and current spikes in my previous abode. And I have not babied it. So while it looks slapped together inside it has been pretty robust. I think the soldering has dried out due to age and mechanical stress vibration, movement and thermal expansion/contraction ( 18,000uf 200v filter caps.) I suspect the three little caps that smoked because they were very cheap caps to begin with, like nad grade caps or worse. Sort of a cascade of death The main filter caps seem fine. And there are a lot of little el caps (like over 50) of the power supply due to its inherently complex design.
But yeah, 30 year old amps are likely to have issues. Even Bryston “only” offers a 20 year warranty. lol. And I think once past a certain age these sunfires build quality and layout are likely to go. It’s just shockingly cheaply built inside. The pcbs themselves look to be very good quality (unlike NAD cardboard and tin foil), but the components used (except for transistors) are pretty cheap and the huge vertical boards are not well supported mechanically and are soldered to each to each other with thick headers and held to the back panel and base by the transistors themselves and the rca input jacks for the most part with the top of the boards just sticking up with no support. So yeah, they are going to flex and solder is going to fail over time from age, micro movement/flex, and or gravity. And not the greatest soldering to begin with.
I understand the “ architects” series sunfire amps are better built (in part because they are smaller in order to fit in racks,,,the 2x300 or 2x600 seems larger than it needs to be to be honest )they use the same chassis size for 7 channel models).
The sunfire av processors on the other hand have always been unreliable and usually can’t be repaired.
The symphonic series amps are VERY rolled off on the high frequencies and kinda boomy on the lows. aka, very tube like.
None of the amps have good SNAID even for their time. The power supply introduces lots of noise and the wire layout cannot help. lol. High powered n core and purifi based tech has rendered the sunfire’s innovations on the power supply efficiencies more than obsolete to say the least while also providing similar power with far far far better SNAID in packages 1/3 to 1/5 the size. And your house lights won’t dim due to inrush.
Currently using the fossi v3 in the tertiary system the sunfire was in. More than enough power for what I need. Here is a fun photo size. comparison. Yeah of course the fossi can’t produce hundreds of watts into 8ohms, but it has far better SNAID at any level I can manage in my office with Jbl studio 530s.
The sunfire is best suited super low sensitivity power hungry low ohm beasts like acoustats, Magnapans, or apogee’s, for which the sunfires noise level is a non issue. And which won’t measure well from a neutrality point of view either no matter how much I might like them subjectively. But no, I would still not use the “special” speaker posts.
