Hi, i have just found this site after looking for advice on repairing my amp and this is my first post, a big thanks.
I have a (home use) separate amp, its a "Pioneer Stereo Amplifier A-X450"; sound is only coming out of one speaker. I have discovered that at the rear of the unit there are x2 (what look like) loops of aluminium that can be removed; the holes for each of these loops are marked "L" and "R", and "In" and "Out". When i touch both of the aluminium loops (with my thumb and forefinger) then the other speaker works (albeit with a little interference). Can anyone advise what the problem is and if it can be fixed. I have little knowledge of electronics as you can probably notice. Thanks for any advice
Mel
I have a (home use) separate amp, its a "Pioneer Stereo Amplifier A-X450"; sound is only coming out of one speaker. I have discovered that at the rear of the unit there are x2 (what look like) loops of aluminium that can be removed; the holes for each of these loops are marked "L" and "R", and "In" and "Out". When i touch both of the aluminium loops (with my thumb and forefinger) then the other speaker works (albeit with a little interference). Can anyone advise what the problem is and if it can be fixed. I have little knowledge of electronics as you can probably notice. Thanks for any advice
Mel
What you are describing is a preamp output to power amp in connector. You might try pulling that connector out and then plugging it back in it might just not be making a good conection.
When you touch the amplifier inputs (i.e the U-shaped metal links between preamp out and amplifier in) you seem to have output from both channels. That's good so far but it suggests that one preamp channel is not working so obviously you can't have the corresponding amplifier output working either.
The easiest way to check what section isn't working is to swap the amplifier input connections from Left to Right to see if the fault swaps too. In this case, you'll have to replace the metal links with longer wires. Solid wire Mains cable scraps, cut to about 50 mm length are good for this but if you have a spare 2xRCA - 2xRCA stereo cable, you can use this in place of the solid metal links.
Fit this cable with the same connections as previous (pre-out L to power -in L and vice versa then check that 1 channel is still not playing. Then, cross the leads over so that pre-out L connects to amp-in R and vice versa.
If the missing channel has swapped over now, the problem is in the preamp and possibly lies in the switches but it takes a lot more patience and effort to troubleshoot the complex signal routes in the preamp.
The easiest way to check what section isn't working is to swap the amplifier input connections from Left to Right to see if the fault swaps too. In this case, you'll have to replace the metal links with longer wires. Solid wire Mains cable scraps, cut to about 50 mm length are good for this but if you have a spare 2xRCA - 2xRCA stereo cable, you can use this in place of the solid metal links.
Fit this cable with the same connections as previous (pre-out L to power -in L and vice versa then check that 1 channel is still not playing. Then, cross the leads over so that pre-out L connects to amp-in R and vice versa.
If the missing channel has swapped over now, the problem is in the preamp and possibly lies in the switches but it takes a lot more patience and effort to troubleshoot the complex signal routes in the preamp.
Last edited:
- Status
- Not open for further replies.