Alesis M1 Schematics?

[presleyhome]

Hey all. I'm looking for schematics for the Alesis M1 Active speakers. I have four of them, about 3 years old. Three are dead. I suspect the power supply, but with out schematic it's abit rough to isolate. Alesis says they have no schematics for them. Something about a buyout from another company, blah blah blah. Useless.

Anyone know where I could get my hands on a set?

Thanks

Jim P

[Zero Cool]

i need schematics for the power supply section should you find any!

[hobby1]

hi
i hade same experience as yours with M1 electronic,power supply HS and no schematic avialable
a simple solution is to change the switchmode supply by a linear one but the M1 power amp need 2 voltage (+- 35V for lm3886 and +- 28V) for the other) one can use voltage reg to make the 28v part with a 36v supply
if it can help

[Zero Cool]

I managed to get my Power supply working but there is still a problem.

I found that there was no power getting to the SMPS controller IC. the resistance to ground on the rail that supplies the IC was very low. I found a shorted 104N chip cap. I replaced that and the supply came to life.

BUT, there is a ceramic 222 cap and a 100 ohm resistor in series and connected to the secondary side of the transformer. once the supply started working, the resistor started to smoke. I replaced the resistor and cap but had the same problem. the supply came to life and continues to work even with the cap and resistor removed. I am assuming this is some sort of noise filter maybe??? and everything on that side of the supply is covered in silicon and i cant see how anything is connected. I am hesitant to run the supply for long without that cap and resistor. the cap that was removed measures fine. its not shorted or anything. and the new one measured fine before and after so im not sure what the problem is.