Hi all,
I acquired this amp three months ago, but with life getting in the way, I literally only powered it up last Monday afternoon. Essentially it runs through a start up procedure, the screen works, a fair bit of relay clicking and then it switches off. My own fault for not checking it sooner. I’m half decent with investigating and repairing, and even managed to get the schematics from XTZ. A lot of Chinese though and could be clearer. One 4700uf 63v cap on the power supply board had leaked, actually leaving a leg on the board. Lots of nasty glue everywhere but I’ve cleaned that away, checked the four main 12000uf caps, and they test within spec. I’ve replaced both 4700uf caps, sorted out a couple if dry joints and thought that obviously bad cap could be the issue. No. Found more dry joints on various voltage regulators and elsewhere. Still no joy. There is no response to any control input apart from power on. The overall build of this thing makes it worth the effort, but if anyone has any ideas they would be much appreciated. I’ve never seen an amp with so many screws, it’s depressing!
thanks
Mat
I acquired this amp three months ago, but with life getting in the way, I literally only powered it up last Monday afternoon. Essentially it runs through a start up procedure, the screen works, a fair bit of relay clicking and then it switches off. My own fault for not checking it sooner. I’m half decent with investigating and repairing, and even managed to get the schematics from XTZ. A lot of Chinese though and could be clearer. One 4700uf 63v cap on the power supply board had leaked, actually leaving a leg on the board. Lots of nasty glue everywhere but I’ve cleaned that away, checked the four main 12000uf caps, and they test within spec. I’ve replaced both 4700uf caps, sorted out a couple if dry joints and thought that obviously bad cap could be the issue. No. Found more dry joints on various voltage regulators and elsewhere. Still no joy. There is no response to any control input apart from power on. The overall build of this thing makes it worth the effort, but if anyone has any ideas they would be much appreciated. I’ve never seen an amp with so many screws, it’s depressing!
thanks
Mat
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Hi Mat.
I bought one of the first ones of XTZ Class A-100 in Denmark back in 2006-2007 and it has been a joy since then. Sorry to hear about your sad experience with this one.
I have repaired stuff like this for many years and amplifier mostly die caused by electrolytics drying out or the output transistors has shortened.
Replace any electrolytic capacitors if they appear 'wet' on the pcb.
It could be a lot of things, but try to measure the output of the transistors for any DC when the amp is booting.
If no DC is present, verify the two power supply rails for preamp and power amp. Preamp should be +/- VCC a bit higher than the power amp.
Anyway, I have been searching for a schematic since I bought it and haven't been able to find anything.
Can I please ask you to share the schematic for me?
Thanks in advance.
Kind regards Henrik Damtoft.
I bought one of the first ones of XTZ Class A-100 in Denmark back in 2006-2007 and it has been a joy since then. Sorry to hear about your sad experience with this one.
I have repaired stuff like this for many years and amplifier mostly die caused by electrolytics drying out or the output transistors has shortened.
Replace any electrolytic capacitors if they appear 'wet' on the pcb.
It could be a lot of things, but try to measure the output of the transistors for any DC when the amp is booting.
If no DC is present, verify the two power supply rails for preamp and power amp. Preamp should be +/- VCC a bit higher than the power amp.
Anyway, I have been searching for a schematic since I bought it and haven't been able to find anything.
Can I please ask you to share the schematic for me?
Thanks in advance.
Kind regards Henrik Damtoft.