Self repair? Three 1500w alto-mac amps

[FoleyQ]

I got my hands on three ALTO MAC 2.2 amps for free. They are all broken in same way. When they are powered they start making this sound which I can only describe as a kind of surring noise. Otherwise they seem to work normally. I'm pretty sure it's caused by broken cooling fans. Has anyone got any experience with these amps? If you know how to replace/fix the fans or have the same issue please tell me I don't want to open them without knowing what i'm about to do.

Also, I don't have anything that can manage this much power, so I think I will sell them if i can fix them. How much do you audiophiles think they are worth?

[TLS Guy]

I got my hands on three ALTO MAC 2.2 amps for free. They are all broken in same way. When they are powered they start making this sound which I can only describe as a kind of surring noise. Otherwise they seem to work normally. I'm pretty sure it's caused by broken cooling fans. Has anyone got any experience with these amps? If you know how to replace/fix the fans or have the same issue please tell me I don't want to open them without knowing what i'm about to do.

Also, I don't have anything that can manage this much power, so I think I will sell them if i can fix them. How much do you audiophiles think they are worth?

I guess those amps are used by bass players. I have never heard of them, but it looks like a company producing junk. They are really cheap, and I would expect them to blow up. I'd give them a value of $100 each used. They are not the sort of amp that any members here are likely to have. They are class D amps. Try guitar forums for more information.