I have a JL Audio 1000/1V1 amplifier on the way that needs repair. I was told that it powers up, but the low ohm light is on and it makes a screeching noise. I am trying to order as many parts as might be needed in advance so I would have them on hand when I open it up. I read all of the 1000/1 posts and am compiling a list but still have some specific questions which may save me some time as I need to order quickly:
1)I have IRF3205 and IRFB31N20D in stock, can these work as power supply and outputs in this amp?
2)Can anyone supply a parts order of the most commonly replaced parts required for this amplifier?
3) Since the amp powers up with low ohm light, does that mean the PS FETs are good and don't need replacement?
1)I have IRF3205 and IRFB31N20D in stock, can these work as power supply and outputs in this amp?
2)Can anyone supply a parts order of the most commonly replaced parts required for this amplifier?
3) Since the amp powers up with low ohm light, does that mean the PS FETs are good and don't need replacement?
Thanks for the reply.
Regarding the PS FETs, is IRLB8721PBF a viable substitute for the difficult to find IRF3707? One of those suppliers recommended it as a substitute. Or should I get the IRF3709ZPBF, as this is the only one I can locate so far.
How many PS FETs does this amp use?
How many outputs does this amp use?
I read that you used IRFB31N20D in some of these. Has that substitution proven reliable? Is there a better substitute that is readily available?
Regarding the PS FETs, is IRLB8721PBF a viable substitute for the difficult to find IRF3707? One of those suppliers recommended it as a substitute. Or should I get the IRF3709ZPBF, as this is the only one I can locate so far.
How many PS FETs does this amp use?
How many outputs does this amp use?
I read that you used IRFB31N20D in some of these. Has that substitution proven reliable? Is there a better substitute that is readily available?
I don't remember using the 31n20 but if I wrote that, I must have. The newer version uses the FDP52N20 with 22.1 ohm gate resistors. I don't know if there are any other changes to the drive circuit.
8 outputs.
24 (?) power supply FETs. When the power supply FETs fail, they sometimes just fail in one group of 6. IT looks like the gate resistor was changed to 22 ohms for the 3709.
I'd wait to see what the damage is before ordering parts.
8 outputs.
24 (?) power supply FETs. When the power supply FETs fail, they sometimes just fail in one group of 6. IT looks like the gate resistor was changed to 22 ohms for the 3709.
I'd wait to see what the damage is before ordering parts.
Good advice Perry. I did wait until I got the amp in my hands and it saved me a lot of expense. When powered up, the amp does exactly what was described to me. The low ohm light is on and it makes a screeching/buzzing noise.
I opened it up and tested all transistors. None of the PS FETs or output transistors showed any shorts or low readings. Everything else on the boards look good with no signs of damage. Then I noticed that one of the 5w 5ohm 'sand block' resistors next to the output filter inductors seemed a little loose. When I removed it, one of the legs had separated. I replaced that resistor and the amp powered up with no noise and only the green power led lit up. Tested the amp on the bench and it gave no problem. Have had it playing in my vehicle for almost a week now with no apparent problem.
Definitely has to be one of the easiest, cheapest JL Audio 1000/1 'for parts or not working' repairs possible. Hoping it continues to operate problem free.
I opened it up and tested all transistors. None of the PS FETs or output transistors showed any shorts or low readings. Everything else on the boards look good with no signs of damage. Then I noticed that one of the 5w 5ohm 'sand block' resistors next to the output filter inductors seemed a little loose. When I removed it, one of the legs had separated. I replaced that resistor and the amp powered up with no noise and only the green power led lit up. Tested the amp on the bench and it gave no problem. Have had it playing in my vehicle for almost a week now with no apparent problem.
Definitely has to be one of the easiest, cheapest JL Audio 1000/1 'for parts or not working' repairs possible. Hoping it continues to operate problem free.
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If the power supply FETs need to be replaced in this amplifier, what is the best course of action? Not finding IRF3707 at any of the reputable suppliers that I normally purchase from: Digikey, Mouser, Future, Arrow, etc. eBay has some from the Far East but authenticity is uncertain.
1) Is there anywhere to locate IRF3707?
2) It was mentioned that newer models use IRF3709ZPBF with 20ohm resistors. Would that be the best first attempt at power supply FET replacement?
3) Is IRLB8721PBF a viable substitute since one of those reputable suppliers recommended it as a substitute.
Thanks.
1) Is there anywhere to locate IRF3707?
2) It was mentioned that newer models use IRF3709ZPBF with 20ohm resistors. Would that be the best first attempt at power supply FET replacement?
3) Is IRLB8721PBF a viable substitute since one of those reputable suppliers recommended it as a substitute.
Thanks.
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