SPL ZX1-3000D

[brandes.cm]

I only buy from Arrow, Avnet, Digikey, Mouser and MCM. I won't buy parts from ebay anytime. I have read to many stories about fake parts.

I just ordered from Arrow, free ground shipping on all orders.

 

[Perry Babin]

The last ones I purchased were from Arrow and I haven't had any problems with them.

 

[brandes.cm]

What about the drivers I believe them to be TO-92L A1023 and C1027. I found a Fairchild cross but no stock of the npn part. The best I can find is NTE31 and NTE32 parts. That is what I am using now.

 

[Perry Babin]

The drivers are the MPSA42s and the MPSA56s.

If the transistors you listed aren't defective, I'd leave them in the circuit. After you get the amp working, if you want to experiment with substitute parts, you can try whatever you'd like.

 

[brandes.cm]

Do the drivers usually run warm? The amp has a fan essentially mounted to the driver board. I assume that is to wick heat away from it. I don't want to mount the output fets only to have something fail and take them out.

 

[Perry Babin]

Q124 and Q125 run extremely hot. In time, they will cause the fiberglass board to become conductive from the heat.

The fan pulls air from the driver board side of the fan but does not produce much air flow over the board or the components. That's why I recommend replacing Q124 and Q125 (with MPSW42s) and installing them so that their body is as close to the fan blades as possible.

 

[brandes.cm]

I will order up some MPSW42's. This amp came to me without a bottom cover, most of the leaded capacitors were bent over; close to shorting to other parts. The power supply and output fet were shorted along with issues on the driver card.

I have a hard time offering up any kind of warranty on this amp.