Ok I have this ZR1000,
Amp powers up and plays fine on left channel, the right channel plays real low.
If I increase the head unit vol then the right channel vol rises as it should.
However when I increase the gain on the amp there is no vol rise,infact adjusting the amp gain makes no difference to the right channel. Left behaves correctly.
I have tried a known fully working replacement crossover module and there is no change.
I have checked the docking port contacts and re-soldered the point it joins the main board and there's no change.
The amp doesn't overheat or blow fuses.
The outputs appear to test ok with no dead shorts.
I'm sure it's just something tiny I must have overlooked.
Any help appreciated on this one ? Thank you
Amp powers up and plays fine on left channel, the right channel plays real low.
If I increase the head unit vol then the right channel vol rises as it should.
However when I increase the gain on the amp there is no vol rise,infact adjusting the amp gain makes no difference to the right channel. Left behaves correctly.
I have tried a known fully working replacement crossover module and there is no change.
I have checked the docking port contacts and re-soldered the point it joins the main board and there's no change.
The amp doesn't overheat or blow fuses.
The outputs appear to test ok with no dead shorts.
I'm sure it's just something tiny I must have overlooked.
Any help appreciated on this one ? Thank you
Ok I replaced U201
also noticed the earth to centre tap fuse was defective
also noticed a metal screw had been used to secure the board - the one by the transformer
And in case the crossover module was bad I jumped the connectors as advised by Perry on another thread.
I turned both bias pots and the gain down and powered it up.
The amp played fine for about 5 mins,
The Right channel was playing a little lower than the left but the gain adjustment was working again.
then the yellow protect led illuminated and there was a loud screeching/hissing noise coming from the transformer and my power supply tripped out.
the outputs look like de801 and de748 pairs?
I expected them to be TIP35 and 36 pairs?
also noticed the earth to centre tap fuse was defective
also noticed a metal screw had been used to secure the board - the one by the transformer
And in case the crossover module was bad I jumped the connectors as advised by Perry on another thread.
I turned both bias pots and the gain down and powered it up.
The amp played fine for about 5 mins,
The Right channel was playing a little lower than the left but the gain adjustment was working again.
then the yellow protect led illuminated and there was a loud screeching/hissing noise coming from the transformer and my power supply tripped out.
the outputs look like de801 and de748 pairs?
I expected them to be TIP35 and 36 pairs?
Are there other numbers on the output transistors?
These amps have a problem with shorted transformers. That could have blown the SMD fuse.
The metal screw would cause engine noise if the amp was screwed down to a grounded piece of metal.
Did the outputs fail?
With nothing connected to the amp, connect one meter probe into the B+ connector and connect the other probe in one of the non-bridging speaker terminals. Set the meter to diode-check. Push/pull/twist the transformer. Does the meter ever show continuity (near a dead short)?
These amps have a problem with shorted transformers. That could have blown the SMD fuse.
The metal screw would cause engine noise if the amp was screwed down to a grounded piece of metal.
Did the outputs fail?
With nothing connected to the amp, connect one meter probe into the B+ connector and connect the other probe in one of the non-bridging speaker terminals. Set the meter to diode-check. Push/pull/twist the transformer. Does the meter ever show continuity (near a dead short)?
- Status
- This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.