Hey Guys,
I recently added a 4 channel amp and components to an already existing sub amp and subwoofer. After the install my subwoofer will Pop everytime the car is turned on and has a low rumble when the car is turned off. This has never happened before the installer placed the new parts.
I checked to see if it was the remote in line causing it, but I unplugged the RCA and it still popped. I also removed the remote wire and plugged it in a few seconds after the car was turned on and it still makes an initial Pop sound. I'm assuming the circuit protector got fried somehow during the install (installer didn't unplug battery during install).
Is there a way for me to get in the amp and fix this myself? This is a Jl 500/v2 slash amp that is way past its warranty but I really like this amp and paid a lot for it to just throw it out for this.
I recently added a 4 channel amp and components to an already existing sub amp and subwoofer. After the install my subwoofer will Pop everytime the car is turned on and has a low rumble when the car is turned off. This has never happened before the installer placed the new parts.
I checked to see if it was the remote in line causing it, but I unplugged the RCA and it still popped. I also removed the remote wire and plugged it in a few seconds after the car was turned on and it still makes an initial Pop sound. I'm assuming the circuit protector got fried somehow during the install (installer didn't unplug battery during install).
Is there a way for me to get in the amp and fix this myself? This is a Jl 500/v2 slash amp that is way past its warranty but I really like this amp and paid a lot for it to just throw it out for this.
I can check, do I just take my multimeter and place the probes on the RCA shield and inside?
I don't think it's an issue with the ground or RCA. My 4 channel amp does not pop when turned on, only my sub amp. Even without the RCAs plugged in the amp will cause the sub to pop. Im thinking the amp's protection circuit got fried somehow.
I don't think it's an issue with the ground or RCA. My 4 channel amp does not pop when turned on, only my sub amp. Even without the RCAs plugged in the amp will cause the sub to pop. Im thinking the amp's protection circuit got fried somehow.
0.2v on BOTH amps? It's strange that both amps with different types of circuits would read the same.
Is the head unit's shield ground OK?
Does the 500 pop if you connect it directly to the head unit without the other amp?
How were you using the 500 before and does it pop in that configuration?
Is the head unit's shield ground OK?
Does the 500 pop if you connect it directly to the head unit without the other amp?
How were you using the 500 before and does it pop in that configuration?
Are you going to measure the other amp. It's possible that there is DC voltage on it that damaged the JL. The problem may also be intermittent.
Are you going to answer the other questions?
This amp is VERY complex and difficult to repair. I want to do everything possible to try to eliminate other issues or to find problems that may have damaged the amp.
Are you going to answer the other questions?
This amp is VERY complex and difficult to repair. I want to do everything possible to try to eliminate other issues or to find problems that may have damaged the amp.
Hi, I was able to measure the 4 channel amp and I didn't read a DC voltage coming from the RCA shields. Im using OEM head unit and using the JL Fix 86. I re-checked all the grounds and they seem to be okay.
I was using the slash amp as a stand-alone with a sub by using a cheap LOC tapped into my rear speakers. Now the RCAs come from the Fix 86. Even when the RCAs are removed the POP sound still occurs when the car is turned on and a low rumble when it's turned off. When RCAs are unplugged the sub will still pop. The only way to prevent the pop is to have the speaker wire to the sub disconnected and reconnected once the amp is turned on. I just purchased a speaker protection module so that I can attach it to the speaker wires leading to the subwoofer so that it has a delay when the amp turns on to prevent the signal from reaching the sub. This seems like the easiest fix, but is there a way to correct this internally in the amp?
I was using the slash amp as a stand-alone with a sub by using a cheap LOC tapped into my rear speakers. Now the RCAs come from the Fix 86. Even when the RCAs are removed the POP sound still occurs when the car is turned on and a low rumble when it's turned off. When RCAs are unplugged the sub will still pop. The only way to prevent the pop is to have the speaker wire to the sub disconnected and reconnected once the amp is turned on. I just purchased a speaker protection module so that I can attach it to the speaker wires leading to the subwoofer so that it has a delay when the amp turns on to prevent the signal from reaching the sub. This seems like the easiest fix, but is there a way to correct this internally in the amp?
Does the power LED go off when you turn the head unit/amp off?
The pop problem that I referred to won't cause the noise when it's off.
If you didn't already know, the output of this amp has 40v DC on it at all times when the amp is on.
As a side note, if you could afford the $400+ head unit adapter, why not just pay JL to repair it?
The pop problem that I referred to won't cause the noise when it's off.
If you didn't already know, the output of this amp has 40v DC on it at all times when the amp is on.
As a side note, if you could afford the $400+ head unit adapter, why not just pay JL to repair it?
Yup, the Power LED does go off, but there is still a discharge.
The Fix 86 was given to me as a "gift" (buddy upgraded his system and didn't have a need for it), and the repair is around 250 from what I researched. Would like to avoid having to repair an amp that was working perfectly fine until an installer touched it. Thought it would be a quick fix but judging from your replies it seems like it won't be
The Fix 86 was given to me as a "gift" (buddy upgraded his system and didn't have a need for it), and the repair is around 250 from what I researched. Would like to avoid having to repair an amp that was working perfectly fine until an installer touched it. Thought it would be a quick fix but judging from your replies it seems like it won't be
The JL amps are the most complex of any that I've seen. In terms of complexity they are a 10 where the large 4ft long (true) 8k watt amps are a 3. We have successfully repaired a lot of them on this forum but you have to eliminate all possible issues otherwise before you think about going into the amp.
Do you have any experience in amp repair or in replacement of SMD components on a circuit board?
The flat rate for these amps was $150. I guess it went up.
Does the 40v DC on the speaker terminals drop to 0v when the LED goes off?
Do you have any experience in amp repair or in replacement of SMD components on a circuit board?
The flat rate for these amps was $150. I guess it went up.
Does the 40v DC on the speaker terminals drop to 0v when the LED goes off?
If it's popping even with no input cables connected I'd say that isolates the amp as the problem. Only other thing you might do is try turning it on with a jumper from +12v to remote, on the off chance there's something goofy going on with the HU. If it still does it, then it's internal to the amp for sure. Could be the output side gate driver going south, seen plenty of that in mono slash amps. Truthfully though diagnosing a problem like this requires a lot of knowledge about the amp internals, and an oscope to see what's going on with the signals that operate it.
Does it pass clean audio still?
Does it pass clean audio still?
I actually did the jumper and it still does the Pop sound. If that's the case I guess the only solution is to go with the Speaker protection module and add it to the speaker wires coming out of the amp. It adds a 1-2 second delay before a signal can be sent through the speaker wire so it'll prevent the POP from ever reaching my sub, but it's pretty much a band-aid as the amp is still sending out the signal.
I contacted JL and they said the repair of the amp is 230+ shipping. I was told they actually just swap the board on the amps so it actually might be worth the hassle. Whats your opinion on this? Better to fix or just go with the speaker protection module?
I also want to thank you for taking the time to reply to all my questions. I really appreciate it!
No problem.
The solution is really up to you, if cost is the issue and the amp still works then the protection module may be your best bet. OTOH if the amp degrades further and winds up taking out an expensive driver and the module doesn't catch it, you'll have to foot the repair bill anyway.
Problem is this type of symptom could be caused by nearly anything, so it may take some bench time to locate the source of the issue. Could be the output side, or any one of the OPAMP's in the audio path failing. I've fixed a lot of these though, so my gut is leaning to the output side driver IC since it's a high fail item.
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Alright guys, something interesting happened.
While I was trying to tune my subwoofer and did an extended sound test to try to EQ it the pop dissappeared. My subwoofer was sounding too punchy and it felt like frequencies in the 80Hz range was overpowering the other frequencies. It was also causing a really annoying trunk rattle that I didn't have before.
While I was trying to set my crossover on my amp, I noticed a slight noise coming out of the subwoofer while I adjusted the crossover frequency. As I was fiddling with the crossover, the sound just stopped. When I turned my car off and on the pop did not happen. It's been a full day now and it hasn't reappeared. Don't know what the exact solution is but I guess my amp fixed itself?
Thank you all for your replies. Im just gonna take this good fortune and hope it doesn't come back.
While I was trying to tune my subwoofer and did an extended sound test to try to EQ it the pop dissappeared. My subwoofer was sounding too punchy and it felt like frequencies in the 80Hz range was overpowering the other frequencies. It was also causing a really annoying trunk rattle that I didn't have before.
While I was trying to set my crossover on my amp, I noticed a slight noise coming out of the subwoofer while I adjusted the crossover frequency. As I was fiddling with the crossover, the sound just stopped. When I turned my car off and on the pop did not happen. It's been a full day now and it hasn't reappeared. Don't know what the exact solution is but I guess my amp fixed itself?
Thank you all for your replies. Im just gonna take this good fortune and hope it doesn't come back.
At this point, if it's working perfectly, I'd suggest leaving it as it is. If you absolutley have to clean them, A good contact cleaner and working them back and forth 50 or so times will get most clean enough.
You should know that some of the switches have plastic shields in the way of getting cleaner in from the outside and therefore require disassembling the amp. I do NOT recommend that unless absolutely necessary.
You should know that some of the switches have plastic shields in the way of getting cleaner in from the outside and therefore require disassembling the amp. I do NOT recommend that unless absolutely necessary.