How did that bring down the whole amp though? Well, without the auxiliary voltage supply circuit running, some residual voltages creep onto various parts of the PWM gen and drive circuit. When rail voltage is applied, this causes one of the halves of outputs to latch the mosfet fully on, transferring full rail voltage to one of the speaker terminals but not the other. With 80V DC at the speaker terminal, the subwoofer voice coil will present its full DCR to the fets, extremely high current will be drawn, causing the fets to fail and short. With the output fets shorted and the overcurrent protection circuit assumedly not running due to the lack of auxiliary VCC, the power supply mosfets are now attempting to drive a dead short, thus overloading and killing them.
@@kensmechanicalaffair there was switching on the power supply, it only stopped after the output fets shorted and subsequently overloaded the power supply fets.
Great video sir very educational I have repaired alot of those amplifiers and its the first time I see one with that problem wow never too old to learn keep up the good work 🇯🇲 🇺🇸 🙏🙏
I've owned 3 Slash series amps (×2 500/1v1 and a 300/2v1), and think they are really good amps (especially for 1997), but a bit overpriced. Repairs though, I didn't find to be fun. One 500/1 had a bad slope selector switch, one had poor connection at 12-pin header connecting xover board to main pcb. Both work flawlessly now. Not bad for 25 years old
Hey barevids, I watched your repair vid on the JL Audio 500/1 V2. How can I check the bass attenuator aka Bass Knob to see if its the problem? I just replaced my 500/1 V1 and its not working..The other 500/1 V1 I was using, it didn't work with that one. I know JL has two models for old versions and new versions.
Opinions on JL amps in general? They seem to last longer than other amps. Plenty of people using decades old JL amps and they still sell for good money used. Are they better built than other brands or is it just because more of them were sold than other companies. Think the JL 500/1 is the best selling amp of all time..
@UHF VHF Sure. But there’s a big difference between well made amps and poorly constructed amps. Design topology, quality of components, component seating, PCB isolation/rigidity etc. There’s a reason most amps seem to last a couple years and some (like JBL, Alpine, Rockford, JL Audio) last decades. I’m interested in the opinion of a professional. What someone who repairs amps for a living thinks about the differences. Or, as you seem to indicate, is it just down to how well they’re looked after
hey bro need some advice on repairing dd c5c one channel blown but cannot find trans mp 2510 locally or online what do u think will be a good replacement ?
I've been watching your videos for a while now and they have definitely helped me repair amplifiers. I've ran into an issue with an amp that I can't seem to figure out. The amp had a capacitor that blew so I removed it and replaced it with a new one. Now my problem is that when I turn the amp on the capacitor will unload out the bottom side of the board. It has a huge blue spark and makes a loud popping sound. The amp doesn't go into protect at all when this happens. I've replaced the capacitor 3 times now and it keeps doing the same thing. Not sure what to do now
I have a jl audio 500/1 that a customer brought me that loses audio randomly but will regain audio when he turns his stereo volume high. Why would that be happening?
Can anyone advise me on fixing an issue with a boss blade 3k mono, the problem is it had a shorted capacitor just after the power input, I changed it and check the others to make sure they were all good then I noticed 2 224j100. Capacitors one cracked and the other blown out the side I then changed those out then powered on the amplifier with a low amperage powersupply and it looks like it work it goes to protect them switches across to power but when trying to input audio signal to it I get no audio out, so I decided to put my other power supply on it with a little more amps and well the amplifier turns on to protect and as soon as it turns on to power it trips my powersupply and powers off back again and back on to the same protection and trip, that leads Me to think it it has something sending back Voltage but I'm not sure can anyone advise on what to check or what cud be the possible cause
Dirty switches could very well be the problem. As he's stated before- 99% isopropyl alcohol sprayed generously "into" the switches while toggling from one side to the other. That will clean the contacts
