Help with Infinity Kappa Four

[Frycztech]

Hello,

I have an Infinity Kappa Four that both left channels play almost no audio, you can very faintly hear some audio playing. Both right channels i can get audio out of. Nothing inside the amp looks burnt. Any help on where to start would be greatly apricated.


Thank you.

 

[Perry Babin]

Has any work been done to it?

 

[Frycztech]

Perry I do not believe so.

 

[Perry Babin]

Have you traced the signal to see where it's being lost in the circuit?

If you don't have it:
https://elektrotanya.com/showresult?what=kappa_four_sm&kategoria=&kat2=all

 

[Frycztech]

Ok thank you. Just use a multimeter? I do not have a scope.

Thank you for the help.

 

[Perry Babin]

Use a sine wave of about 60Hz. Set all crossovers to flat. All gains to max.

Starting at the RCA jacks, compare the signal levels through the circuit.

 

[Frycztech]

Hey Perry,

So I keep trying to follow the signal but I keep losing it when I get to the raised board that holds the gain controls and I am not sure where it outputs to see if it is coming out of not. Do you what any insight where i should test coming out of the board to see if it matches what is going into the RCS jacks?


Thank you

 

[Perry Babin]

Did you download the service manual?

 

[Frycztech]

Yes but I keep getting lost on the raised gain control board.

 

[Perry Babin]

What is the last op-amp output pin where you see signal?

 

[Frycztech]

That the problem the op-amps are on the bottom of the gain control board and I cant test them while the board is connected. I wanted to try to see if there was any way to test from the top of the board.

Thank you for your help

 

[Perry Babin]

Is the preamp board connected to the main board with pluggable headers?

 

[Frycztech]

Yes but if I remove it I wont be able to power it up. I didnt know if there was a way to check on the output to see if that was an issue or if it is past that

 

[Perry Babin]

You can make extension cables out of ribbon cable and male/female connectors that will allow you to check everything you need to check with the board connected.