Call for help. Route 66

[topdog360]

I have a route 66 with a weird problem occurring. Im using the 66 with an Alpine PXE-H660 processor. When the 2 are connected, and the Alpine turns on, the fuse in the "25" side of the 66 immediately pops. The "44" side works just fine. As an experiment I connected my ipod directly to the amp and everything works without popping a fuse. So for some reason only the "25" side doesnt like the Alpine processor. Something to do with them being on the same power Im guessing. Any ideas?

[ttocs]

have you checked your rca's for continuity to ground?

Have the caps been replaced in that amp?

[topdog360]

Caps have been done, by eric im told. All outputs of processor
work on "44" side, pop fuses on "25" side.

[ttocs]

try running a new temporary rca from the processor to the amp and see if it does it with that cable too.

[topdog360]

I've tried that. Its not cabling or speaker related.

[Eric D]

My best guess on that one is there is a short in the transformer which is shifting the ground point of the amp. When you connect the Alpine, its RCA is shorted to ground, and this current demand pops the fuse.

Hook up the amp with new fuses, and nothing connected to the RCAs. Then measure the voltage (DC) between one of the middle speaker terminals on the M44 side and one of the middle speaker terminals on the M25 side. The middle two speaker terminals on both sides of the M44 and on the output of the M25 all go to ground. You should measure 0V doing this.

Also measure from the (-) power input of the amps to one of the middle speaker terminals on each side. This too should be close to 0V DC.

If you get a few volts on any of these measurements, there is a good chance one of your transformers has a short in it.

[topdog360]

Eric, im going to check this when I get home. Just a quick question though. Wouldn't a rca shorting to ground cause a current draw on both amps? Only the 25 side pops....44 side works perfect.

[topdog360]

Eric, I measured what you asked. Between "25" and "44" speaker terminals I get around .2 volts which Im guessing is OK. However from ANY speaker terminal on either amp to GND I am getting 12volts!!! I am guessing thats NOT good.... The other thing is when you say middle terminals you mean negatives right? Either way ALL terminals measure 12v between terminal and GND. Please advise.

[mhyde71]

okay so coming in on this one... and is certainly very wierd...weird indeed.

the amp was re-capped by eric (yes), and i assume he benched it prior to sending back to me. before shipping it to you the first time... i know tim and I both benched it. then when amp came back to me for the fuse popping issue, i gave it over to tim, and he looked at it, and said it was looking fine, and ran a 2ohm load on it over night before giving it a bill of health to be sent back down to you.

this is puzzling...but maybe it is just as eric indicated.


i will also have tim maybe look in on this.

[topdog360]

Yeah strange indeed. Especially that when using an external source.ipod(not connected to car gnd) everything works fine. Only pops fuses when using Alpine(obviously same pwr,gnd) AND only "25" side of 66.
Any idea the gear used when it was benched?

[Eric D]

By any speaker terminal, are you talking the outer ones or inner ones, or both?

That amp has 12 speaker terminals in all. Are you saying you get 12V from any of the 12 to ground (- battery terminal)?

You should not be getting 12V, that is for sure.

[topdog360]

That's correct. Amp with green power indication, no rca`s connected. I measure ~11.6v DC between ALL 12 speaker terminals and GND.

[Eric D]

Check the voltage between the battery ground, and the RCA shield. I assume it will be 12V like the rest of the speaker terminals are. If it is, you probably have a short in the the transformer somewhere. It will be hard to find, but just moving the transformer leads around a bit might eliminate it. At least temporarily. (do this with the amp off)

[topdog360]

The transformer on the 25 board?

[mhyde71]

to answer the ? about what gear is used to bench...
Tim has this set up, what i call his watts towers...but they are known as something else...but it allows you to drive a 2 ohm (i know for sure), perhaps other loads as well...but he ran it on that overnight i believe driving it under a 2 ohm load...

and prior to do doing that , he measures everything on board before tieing into the "watts towers" and if all goes smoothly, he will run a signal through for the night just the same.

not sure what eric has for gear or diagnosisng stuff...and if not mistaken this was the 66 that eric not only did caps but also did resistor mod... so i am 100% confident that eric would have benched it though.

BUT and lastly for me I have simply a 50A power supply, and ipod, cd, htc phone, or even cassette tape for sources.

tim says that, and said in same breath that he would have to think maybe little more about what he is about to say...but he is inclined to think that if there was a short in the primary winding, he wouldn't have gotten the 25v 33v measuring ...and how many other windings there are he was/is not certain of w/o looking or whatever....or something like that...i tried taking notes when he was talking, but couldnt keep up 100%

If dc is on the outputs, theres big trouble little china... BUT he ran the watts towers, and signal as did I before shipping it the first time, and it played music...think maybe i even have video of it. On second time round, it was only tim that benched it, but did his normal protocol once again.

[topdog360]

Again, with an ipod directly connected as source, amp plays fine. Only when tied into the same 12v as the source does the amp pop fuses. Im not trying to say you didn't bench it, just that the problem may not have shown up on the bench.

[mhyde71]

Right no, i know travis...i was just saying/stating facts and hoping/thinking that may shed some light as to what the problem might be.

Tims gonna check thread out too...but tbh, not quite sure i heard of anything like this.

M

[Mr. Wild]

Seems like the ground of the M25 amp is connected to +12V. This is why everything is at +12V. Could be a short in the transformer or PCB.