I'm thinking upgrading my pro MOS-2050 to to an Xtant 1001dx and unfortunately I'm gonna lose space for my Rubicon 300/2 for fill. I've found a spot under my rear seat where my Class A 50II will fir but unfortunately one channel is posessed on that amp. I found an old D60 on Ebay, but its just that, OLD.
I was wondering if anyone makes a really small amp anymore(less than 8 1/2 x 7 x 2 1/4 inches).
The only amp I've found small enough so far is this Xtant:
For rear fill, mono is actually more desirable than stereo is. So any amp that would put out the power you want into an 8 ohm bridge would work. That Xtant would be good, and I doubt you'll find many that put out more power for the size.
I don't need much power. I was using a Class A 50II until one channel started acting up. That Xtant is absolutely the only modern day amp I've found that will fit but I don't think it will work either. It looks like it only has one input rca which means no internal summing amp, which means I'd only be able to run "one side" off my xover. This would sound stupid. I guess I could build a lil summing preamp, but that sure seems like a lot of effort just for a bit of fill.
Arggggg! Guess I either get the 50II fixed or wait for another baby Soundstream to show up on Ebay. I tried off the h/u and was appalled by the SQ. :P
Well I've got the summing right and left channel thing solved, well kinda. My 4180c provides a summing option for its front/rear outputs and since its bridged(front=left, rear=right) it'll give me a summed left and right output.
The only problem is I lose fader control at the head unit and rear level control at my FRX 456. I'm not sure I even need that xover anymore w/o my PPI. Should I yank that thing out? It seemed like my imaging/stereo separation improved after I installed it. My Alpine has 4 volt preouts and the 456 is 8 volts max out.
Oh and what happens when you bridge an amp which has intermittent problems on one channel? Will I lose output completely if the one channel goes? or just half the power.
I guess I could run the rear fill off the one "good" channel until I get somethin mo betta.
Bridging would eliminate all sound. It combines the transistors, one being pos. and one being neg. anyway, you'd kill one side, it'd be the same as disconnecting a speaker wire. As simple as a Class A amp is, I don't think it'd be too difficult/expensive to get yours fixed, and it seems it's your best route.
and maybe take a crack at fixing amps in my spare time. I've got some basic background knowledge and kinda thought it would be fun(plus a good excuse to by some neat equipment). You don't happen to know anyone who's purchased that CD do you. That site is huge and that guy seems really well informed.
I personally don't know anyone, but Glasswolf knows the author of that site. He's very knowledgeable, I'm sure the cd is well worth it. If you've ever worked on electronics, amps aren't terrible, I haven't cracked your particular amp, but being a Class A I bet it's not bad at all. It could be as simple as a solder point from what you describe, and a lot cheaper and better SQ than that Xtant Class D. Some audio shops will fix amps for you or be willing to ship the amp to the company for repair if you're not comfortable with it after you crack the amp.
I've got basic some basic soldering skills and know a lil about oscilloscopes and such from some of the acoustics and electronics labs I had back in the day. I've designed and built logic circuits(on breadboards), but am not very familiar with the linear stuff. I did manage to get some free op amp replacement samples from Texas Instruments for an old PPI Xover so I know how to read a data book. Diagnosing and troubleshooting is another story.
As far as transistors go, you can test those with a voltmeter. Depends on if they're silicon or germanium, but they maintain an internal voltage, around .7V for silicon and .3 for germanium. You can start there. Look for bad solder points, fried electronics to start with. It's only for one individual channel, so it can't be horrible. I'd crack the amp first and see, you may see what it is right off and not even have to order the cd.
I cracked it awhile ago looking for burnt resistors etc. but since its an intermintent thing I don't know where to start. It might bench just fine but start cuttin in and out when I get it back in the car. When it works it works great. I wonder if there's any thermal protection circuitry. I forgot what a thermistor looks like. Ok, now I haveta go look inside it again. lol, great.