Krell KSA-250

[WOPL Sniffer]

Yep, it's junk and the weak spot of the amp.

If it wasn't for the sense Protection IN, on the bottom left, I'd just tear it all out.

 

[Gepetto]

My design slaves the DC protect relay to the soft start. When the soft start has the bulk caps near terminal voltage, it clicks in both the resistor shorting relay on the soft start circuit and the output load relay.

In that manner you take longer for the amp to come on but you do not scorch boards in the process. It would appear that the shorting relay failed at one time or another and the amp was running with the resistors in series all the time...

 

[WOPL Sniffer]

My design slaves the DC protect relay to the soft start. When the soft start has the bulk caps near terminal voltage, it clicks in both the resistor shorting relay on the soft start circuit and the output load relay.

In that manner you take longer for the amp to come on but you do not scorch boards in the process. It would appear that the shorting relay failed at one time or another and the amp was running with the resistors in series all the time...

I think the excess heat caused the failures and

 

[WOPL Sniffer]

The board is so cooked now, it's either replace it (none available), reproduce the board (maybe), or part out the amp which is a waste as they still go for good money when finished. But...... What can ya do...........

 

[Gepetto]

I can give it some time to give you some suggestions but not right now. I don't know how long you can wait on it. Is that small auxiliary always on?

 

[WOPL Sniffer]

Small Aux????? You mean the Protection In????

 

[WOPL Sniffer]

I can give it some time to give you some suggestions but not right now. I don't know how long you can wait on it. Is that small auxiliary always on?

The protection in is always hot since it monitors each channel.


If you come up with anything, let me know.

 

[WOPL Sniffer]

I can give it some time to give you some suggestions but not right now. I don't know how long you can wait on it. Is that small auxiliary always on?

I'll make it worth your time Joe...... Nobody rides for free

 

[Gepetto]

Small Aux????? You mean the Protection In????

 

[WOPL Sniffer]

View attachment 74319

The whole board runs all the time unless the amp is In Protection, but yeah, it runs all the relay coils I do believe.

 

[WOPL Sniffer]

This project is history. It has found a new home.