Sunfire True Sub not working.

[MatthewB]

So a little over a year ago a buddy gave me a Sunfire True Junior subwoofer with a beefy 8" driver. The driver and passive radiator are in great shape. The issue is the amp is shot. It just gives a slight hum when turned on and no bass. So I took it my usual audio repair place and the guy who has fixed many items for me is at a loss. It has very proprietary design and he cant get access to any design to fix the issue so after a year of trying he emailed me to let me know he cant fix it and to come pick it up. Now there is a guy I found online who used to work for Sunfire and now owns the company or title to the Sunfire name and has direct access to Bob Carver. He charges $280 straight fee to fix any Sunfire amp better than new. Now I'm not sure what to do. Do I fork over three Benjamin's to ship and repair this amp on a sub that is approaching 20 years of age. Or can I buy an amp with same plate dimensions and just attach to the box and use that. Driver is a 3.3 ohm attached to a 1200 watt amp but from what I hear it only uses 300 watts at 8ohms typically. I've known the owner since he bought the sub 20 years ago and to say this sub has never been driven hard is an understatement. He listens to light jazz, Sinatra, Perry Como at normal volumes. I would hate to just toss out the sub when the drivers are in great shape. So do I buy a replacement amp at say 300 watts, do I buy a sub kit from parts express, can I put the driver in my Def Tech Prosub 800 which also has an 8" driver or do I fork over 300 to have the amp repaired.

 

[Haywood]

I would just give the thing a decent burial at this point. Also, you cannot just stick any 8 inch driver into a speaker that takes an 8 inch driver. There are a lot of differences between drivers and the crossover in your speaker was build for the drivers that came in the speaker.

 

[mazersteven]

You stated a "Buddy Gave You" the Sub. So I take it that it was Free. So if you had to invest $300 that to me would still be a good deal.
You can answer your own question
1) is the Sub still in great condition that if you invest $300 it should work fine for many more years?
2) can you get better performance purchasing a new $300 Sub?
Or you could just give the Sub to Huey so he could make another Shine Box out of it

 

[Wardsweb]

Personally, I would pull the amp out, fill the hole with some 3/4" MDF, and recut it to fit a $99 300 watt D-class amp from Parts Express. It's a good bang for your buck fix and you can use the other $200 for some other toys.

 

[MatthewB]

Actually today went to pick the sub up and my repair guy Gary very nice guy wouldn't even take any money because he couldn't fix it even though he invested over a hundred bucks of his own money trying to fix this had a brilliant idea. He said he could easily convert this sob to a passive sub and just hook up a separate amp as long as the amp has a built in crossover and I could use the sub without using the busted amp built in. So we are going this route. I have two spare Dayton Audio APA 150 amps and i can use one of them as my amp. Hook an rca from the sub out on my receiver to the left line in on the Dayton then another rca from the left line out of the Dayton amp to the line in on the sub. Dayton claims in bridged mode using mono that i should see 250 watts at a 4 ohm load. The driver is a 3.3 ohm driver so I should easily be able to get 250 watts. As I'm gonna use the sub strictly for music in my bedroom that should be more than enough.

 

[Towen7]

So basically ... what @Wardsweb said

 

[MatthewB]

So basically ... what @Wardsweb said

Yes but I wont need to destroy the subs enclosure I can keep everything the same. Gary will rig the amp section by disconnecting the piwerfeatures and allowing me to still use the line level or speaker inputs and attaching whatever power amp I want. No need to cut and attach MDF and back fill the box.

 

[Deacon]

So basically...a lazier version of what @Wardsweb said.

 

[Deerhunter]

Sweet glad to see you found a work around.