Hi, I'm posting this just for future reference, as I found no service information on these amplifiers online whatsoever.
The internals of the EAW CAZ-series are nearly identical to the Alto Mac 2.2, Mac 2.3 and Mac 2.4 amplifiers. Alto Macro 830, 1400 and 2400 are also very similar. I figured this out by googling the part numbers on the PCBs.
Repair manuals and schematics for the Alto amplifiers are easily found if you look for them. This brings me to another issue. The alignment procedure in the service manual for the macro series is missing, however in the manual for the mac series the alinment and test section is present. I believe the procedure used in the mac series repair manual can be used also for the macro series amplifiers.
EDIT: just as a follow up:
on the CAZ 1400 (similar to mac 2.2 or 2.3) all I did was replace output transistors. i spent a day matching up quads, then put them in.
On the CAZ 2500 (MAC 2.4) the problem was more tricky to track down. One of the input capacitors was bulging and 2 fuses were burnt. After going down the wrong path serveral times I realized that there was a bad connection on top of the board between -55V from the rectifier board and its corresponding filter capacitor on the amplifier board. This resulted in reverse voltage across capacitor C222 which caused it to short and spill its electrolyte. Connection was broken between E215 and C222 negative terminal as the leg of the capacitor had failed to make proper contact with the pad. Installing the new part I could only make intermittent contact so I had to add a wire underneath the board to properly solve this. I had already replaced all four filter capacitors, but I'm guessing C222 (possibly C223 as well) was the only one being damaged by this. Good thing I powered this thing up with a light bulb in series with the power connector effectively reducing the line voltage and all voltages within - or I would likely have blown up the new capacitor as well.
The internals of the EAW CAZ-series are nearly identical to the Alto Mac 2.2, Mac 2.3 and Mac 2.4 amplifiers. Alto Macro 830, 1400 and 2400 are also very similar. I figured this out by googling the part numbers on the PCBs.
Repair manuals and schematics for the Alto amplifiers are easily found if you look for them. This brings me to another issue. The alignment procedure in the service manual for the macro series is missing, however in the manual for the mac series the alinment and test section is present. I believe the procedure used in the mac series repair manual can be used also for the macro series amplifiers.
EDIT: just as a follow up:
on the CAZ 1400 (similar to mac 2.2 or 2.3) all I did was replace output transistors. i spent a day matching up quads, then put them in.
On the CAZ 2500 (MAC 2.4) the problem was more tricky to track down. One of the input capacitors was bulging and 2 fuses were burnt. After going down the wrong path serveral times I realized that there was a bad connection on top of the board between -55V from the rectifier board and its corresponding filter capacitor on the amplifier board. This resulted in reverse voltage across capacitor C222 which caused it to short and spill its electrolyte. Connection was broken between E215 and C222 negative terminal as the leg of the capacitor had failed to make proper contact with the pad. Installing the new part I could only make intermittent contact so I had to add a wire underneath the board to properly solve this. I had already replaced all four filter capacitors, but I'm guessing C222 (possibly C223 as well) was the only one being damaged by this. Good thing I powered this thing up with a light bulb in series with the power connector effectively reducing the line voltage and all voltages within - or I would likely have blown up the new capacitor as well.
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