[stocker08]

A friend of mine recently gave me a JBL Powerbass PB10 subwoofer that had been lying around for a couple years. I am having trouble getting it to power up. I have the sub hooked up to my onkyo receiver through the subwoofer preout, and have the sub turn to "on" in the receiver menu. Problem is, the sub refuses to turn on. There doesn't seem to be a power switch anywhere on this particular sub (whereas the PB12 does). Anyone have an idea? I guess it is also possible that the amp is not functioning properly, but my friend said he was pretty sure it should be working.


Any input would be greatly appreciated.

 

[wwinkler]

You might try a different cable from the receiver to the PB10.


You can check the amp by connecting an mp3 (or dvd) player directly to the line input of the sub amp. Make sure that you turn the gain control down before you do this. You can also do the 9 volt battery test by connecting the battery to the driver (plus and minus) to see if it moves.


The amplifier may be dead. A number of related JBL and Infinity models had very poor life expectancy on their amplifiers. It most definitely is not worth fixing except possibly to purchase a replacement plate amp and install it yourself. Parts Express and OAudio make well regarded plate amps.

 

[stocker08]

Thanks for the ideas. Sorry about the slow response. I think I may just try out a buddies sub on my system and the JBL on his. See if that will put my dead amp theory in place. Too bad they didn't incorporate a power switch on this one like they had with the other. It would have made it much easier to diagnose.

 

[stocker08]

So I pulled out the amp to see if there were any irregularities. Turns out the fuse was blown. It is a slow blow 1.25 amp 250v fuse. I replaced it with a fast acting (don't ask me why) 1.5A 250v fuse, because radio shack doesn't carry 1.25A. The new fuse blows right away. I hear a "pop" when I plus the sub in.


I read that it is possible that too much current is being drawn upon receiving power to charge the caps. Since the sub hasn't been used in at least 4 years, this seems like a possibility. Would it be worth picking up some slow blow 1.5A fuses?

 

[stocker08]

So I went and grabbed some 1.5A slow-blow fuses and sure enough, they still blow. Does this mean the amp is pretty much useless?

 

[Secret Squirrel]

Yes, If it's still blowing new fuses you have a problem. They blow fuses for a reason.

 

[wwinkler]

"It most definitely is not worth fixing except possibly to purchase a replacement plate amp and install it yourself. Parts Express and OAudio make well regarded plate amps." The 240w PE plate amp is currently on sale (~$100). You would need to do some cutting, etc. Alternatively, it is sometimes possible to put 2"x4"s in a rectangular shape that is glued to the back on the subwoofer and install the plate amp to the 2"x4"s.


As a basic starter subwoofer, many individuals in this forum like the BIC F12 (~$200). You could check the BIC F12 thread on how to get the best price.

 

[stocker08]

Thanks for the help fellas. I think I am likely going to just dump this sub, as I really do not want to put any money into, and I don't want to fashion up a new amp to fit the current box. I will check out that BIC.

 

[stocker08]

Any chance that the blowing of these fuses has anything to do with me plugging it into a surge protector?

 

[qguy]

Not unless the surge protector is busted, What do you have to loose, replace the fuse and try it