Fixable problem with my power amp headphone out?
Jun 29, 2008 at 10:50 AM Thread Starter Post #1 of 5

DefectiveAudioComponent

Headphoneus Supremus
Joined
Jan 20, 2008
Posts
3,017
Likes
93
My Pioneer A449 power amplifier is getting a bit old, and now I have to turn up the main volume (it has only one volume knob used also for headphones) a bit for the left channel to kick in. The right channel sounds fine at once, but first there is some static on the left, and then it it sounds likes it physically goes through something and then it sounds fine.

Does anybody recognize this issue?
 
Jun 29, 2008 at 3:27 PM Post #3 of 5

Penchum

Headphoneus Supremus
Joined
Oct 31, 2006
Posts
3,369
Likes
25
Quote:

Originally Posted by Zorander /img/forum/go_quote.gif
A dirty pot, maybe? Applying contact cleaner on the rotating mechanism (assuming this is an analog pot, not a digital one) should solve this.

Cheers!



X2! I have had the exact same thing happen and it was a dirty pot. The channel imbalance is what fools you. Its a super easy fix and you'll be up and running fast.
smily_headphones1.gif
 
Jun 30, 2008 at 5:48 PM Post #5 of 5

DefectiveAudioComponent

Headphoneus Supremus
Joined
Jan 20, 2008
Posts
3,017
Likes
93
I think I fixed it. I put some electronics oil on the moving parts. There are some moving parts along the edge on the right side of the photo here, and also in the middle of the board further away.
(The headphone jack is not shown, but is on the boards on the closest part of the picture.)
attachment.php


Maybe it can be seen better on this photo.

attachment.php

The main volume pot is on the front right, and the moving parts on the board are in the back, to the right.

 

Users who are viewing this thread

Top