This amp had a blown out the IRFZ44N pieces when i replaced those the amp works great now. My problem is when you take power away from the remote turn on wire the subs put out a loud quick thud or pop. What would cause something like this to happen? is it in the power or preamp section of the amp and what should i do to fix it?
did it do that before you replaced those other parts??
usually the thud is the power supply caps discharging, and the quickest way to get rid of that is hooking a relay up between the amp output and the speaker, and hook that up to the remote wire (if its a 12V relay)
look around in the car audio section - there's more info there
usually the thud is the power supply caps discharging, and the quickest way to get rid of that is hooking a relay up between the amp output and the speaker, and hook that up to the remote wire (if its a 12V relay)
look around in the car audio section - there's more info there
Generally, the muting circuit prevents the amp from popping. Many of the class D amps use relays for muting. If this amp uses a relay and the relay isn't opening quickly enough, that could cause the amp to pop.
You can hear most relays click when they open and close. The relay should click approximately 5 seconds after remote voltage is applied and should click as soon as you remove remote voltage (no delay). If it isn't clicking as soon as you remove remote voltage, the drive circuit for the relay is likely damaged.
You can hear most relays click when they open and close. The relay should click approximately 5 seconds after remote voltage is applied and should click as soon as you remove remote voltage (no delay). If it isn't clicking as soon as you remove remote voltage, the drive circuit for the relay is likely damaged.
Perry can you show me with your photos on any amp what the relay looks like? and what drives them?
Not all have relays. I can't find any internal photos of the DQ version. If you can send me a good quality photo of the internals, I'll see if I can provide more information.
babin_perry@yahoo.com
babin_perry@yahoo.com
Perry i will get photos for you if you were interested i just decided that im not going to fix it. I removed all the stereo equipment from my car so ino longer need help with it.
I'd like to have the photos. If you send them, please zip them to files less than 10megs each. Yahoo mail can't handle more than that on incoming email.
Perry I decided I need to fix it. here are some ok pics i cant get a better camera at the moment
http://s227.photobucket.com/albums/dd146/mxracer592/A1200DQ/
http://s227.photobucket.com/albums/dd146/mxracer592/A1200DQ/
You need to check your driver board to see if it's become conductive. The easiest way to check this is by shining a bright light from the back of the board. In the image below (link) you can see how the area between the solder pads has become blackened. You can't generally see this from the outside. You have to use the light so you can see the inside of the board.
Does your board have the darkened area shown in the image?
http://www.bcae1.com/temp/cuttraceondriverboard.jpg
Does your board have the darkened area shown in the image?
http://www.bcae1.com/temp/cuttraceondriverboard.jpg
Ill check when I get out of work. questions. A. if it is like that what is the next step? and B if it is not like that were should i be looking next?
Perry it looked good im taking in out right now for further in spection also could a bad diod by the IRFZ44n's cuase this?
If you pull the driver board, power it up to see if it still pops when powering down.
Remember... Have the transistors clamped to the sink and have a relatively small fuse in the power line when testing.
Do you have an oscilloscope?
I doubt that anything near the FETs would cause it to pop when powering down. Which diode is it?
Remember... Have the transistors clamped to the sink and have a relatively small fuse in the power line when testing.
Do you have an oscilloscope?
I doubt that anything near the FETs would cause it to pop when powering down. Which diode is it?
There is a diod by almost every transistor. I do not have an oscilloscope but i may be able to get one.
In the audio section, there are diodes near each of the outputs. In the power supply, there should be 2 diodes per bank/group of FETs. Those diodes are not likely to cause the output to pop when the amp powers down.
If you had a scope, you'd need to check to see how quickly the voltage on the drive-enable pin transistions from low to high when the amp shuts down. You may be able to see it if your meter responds quickly enough. The pin is #6 on the driver board counting from the RCA end of the amp. The voltage will be ~80v while the amp is muted and very near 0v when the amp is not muted. To prevent popping, the amp should mute instantly when the remote voltage is removed.
Have you removed the driver board yet? If not, check this first.
If you had a scope, you'd need to check to see how quickly the voltage on the drive-enable pin transistions from low to high when the amp shuts down. You may be able to see it if your meter responds quickly enough. The pin is #6 on the driver board counting from the RCA end of the amp. The voltage will be ~80v while the amp is muted and very near 0v when the amp is not muted. To prevent popping, the amp should mute instantly when the remote voltage is removed.
Have you removed the driver board yet? If not, check this first.
Recheck it one more time.
When the amp initially powers up, the voltage will rise with the rail voltage. After the mute delay (red light goes out), the voltage will drop to 0.2v (approximately).
When the remote voltage is removed, the voltage will 'instantly' go back to rail voltage. Since the rail voltage will begin to drop as soon as the remote voltage is removed, you have to read the voltage as quickly as possible (have meter connected while disconnecting the remote).
Reading it like this, does the voltage only go up to 8.6v when the remote is disconnected?
Also, confirm that it's near rail voltage (~80v) before the red LED goes off.
When the amp initially powers up, the voltage will rise with the rail voltage. After the mute delay (red light goes out), the voltage will drop to 0.2v (approximately).
When the remote voltage is removed, the voltage will 'instantly' go back to rail voltage. Since the rail voltage will begin to drop as soon as the remote voltage is removed, you have to read the voltage as quickly as possible (have meter connected while disconnecting the remote).
Reading it like this, does the voltage only go up to 8.6v when the remote is disconnected?
Also, confirm that it's near rail voltage (~80v) before the red LED goes off.
rail voltage is that hig. I got same result. Also perry my amp it just does turn on blue light instantly. i remember on my other amp a18001dt the red light came on first then powered on.
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