Rockford Fosgate Punch 500x 4 channel

[Perry Babin]

I should have been more clear. The black probe will be on the emitters of the transistors you're measuring voltage on (the A06 and A56).

 

[seankane]

I should have been more clear. The black probe will be on the emitters of the transistors you're measuring voltage on (the A06 and A56).

The base of the A06 reads: -29.68

The base of the A56 reads: +29.14

I also mislead you previously I had just woke up and was not thinking. With Q405 and Q406 removed the dc is gone. I would like to re install them and see if the dc comes back because last night when I changed the A06 and the A56 I had the A06 installed backwards. Dont ask how, I have never done that before, dont know what I was thinking.

How do those readings look?

 

[Perry Babin]

If the DC is gone, you can reinstall Q405 and Q406. I was looking for the cause of the DC.

 

[seankane]

If the DC is gone, you can reinstall Q405 and Q406. I was looking for the cause of the DC.

I re installed the Q405 and Q406 and no dc on the bridging terminal.

I traced back into the board a bit last night and replaced Q412, Q413, Q414, and D401. Between these compnoents and replacing the A06 and A56, I might have fixed the problem.

I am not 100% sure though. I guess i need to try and set bias and test for audio, or should I test for audio before I set the bias?

 

[Perry Babin]

You can play it for a few seconds with no bias to see if it produces clean audio. To play it longer or to set the bias current, you'll have to clamp everything to the sink.

 

[seankane]

The audio is clean and sounds fine I will try and bias.

 

[seankane]

All channels biased as they should, gonna grease it up and re clamp it and run it hard to test the solder joint on the transformer.

What did you say to look for? Just make sure that point does not get hot on the transformer?

 

[seankane]

Running at 2 ohms stereo on the rear channels and 18" sub bridged at 4 ohms off front channels. So far it is working great. I will run it hard and get it hot and check the solder joint on the transformer.

Thanks again for all your help Perry.

 

[seankane]

The amp performs flawless. Im running it hard and getting it nice and hot. Shooting the transformer with the heat gun it never gets over 103F in any spot including the solder joint, so I am going to have to say its good. The output fets are running around 130F and staying, the sink is absorbing heat fast and getting warm. 2 ohm stereo and 4 ohms bridged is a good load for this amp, I think it will be fine as it is still running as we speak.

Thanks again for all your help...........