HAVE checked that the volume is turned up have you?
Yes, I did check. Started out checking this before doing anything else, making sure that it was not at an ugly high setting so it would blow the speakers

Also checked fader, balance, pause.
Tested REM-out; measured voltage; the whole works.
Tested speakers/leads; speakers produced a soft pop when leads were connected to small battery.
Tested if speakers were shorted..
Replaced the amp with another one (we did all of this in the car hifi fitting station): no improvement.

Then: voltage on amp proved to drop when the amp set in.
I had measured the voltage on the amp to drop to 0V within a second after it was activated before (one of the reasons for returning it). Now we found the same behaviour, using one of these light pens that glow up (red light) when power is detected between the probe and earth. Without load, the light was bright. As soon as the amp kicked in, the light would fade to a very output within a second. After some minutes (power disconnected from amp) voltage would recover / light glowing bright again. We traced this back to the fuse mounted near the car battery. Replaced the fuse. This cured the power drop, but still no output in the car.

When empeg proved to drive the speaker from the cinch connectors for home use (connected from the bench, outside the sled), a faulty amp or peaker wiring were eliminated from being the cause of the problems. The shop guys (very helpful / interested on Empeg) had me convinced that the fault had to be in Empeg.

Very late last night / early this morning, the guys started to rebuild everything that had been taken apart.

And then (I had left Emma in playing mode), it suddenly decided to drive the speakers! Problem gone. But I'm very puzzled and worried now:

- Is there anything in Empeg than can it make to loose (and pick-up again) all 4 channels at the same time? Is there any single point of failure the 4 channels share? Any protection circuit/fuse or fault condition that can cause it to loose car-out, not cinch-out?
- Could a software upgrade (9a or 9b) have muted all car output?
- Anyone know any kind of failure that could cause a fuse failure as described?
OR
- Do I have an intermittent amp problem?

Remember:
- Empeg was removed (for the bench test) and re-inserted before it came back
- Empeg/Amp had lost all output after pops before I sent the amp back. Sound usually came back within 5 minutes after a pop, except the last time (before I sent the amp back, believing it had died)
- I'm about to fit a larger disk and will only do so on a healthy Empeg.

Henno
# 00120