kx kicker 1500

[timwebb]

I got one of these to fix... I got the amp to power up and play. When the bass hit its really distorted. But at low volume it plays ok. Any thoughts on what to check?

[timwebb]

i traced it back to the ir4426 thats putting out the bad drive signal on half of the outputs. do these ic's normally fail?

[Perry Babin]

Are you sure that this isn't a ZX amplifier instead of a KX. I don't remember the 4426 being used in the KX series amps.

I've never seen one fail in the ZX series amps but I haven't had to repair many.

[timwebb]

oh yes its a zx.

[timwebb]

the amp plays fine but there is a bad signal coming from the one on the right.

[Perry Babin]

Post a photo of the bad signal.

[timwebb]

volt/div 1 time/div 5us

[Perry Babin]

Please read the 'Best Initial Settings' section on the oscilloscope page (page 73) of the site and re-post the waveform.

[timwebb]

...

[Perry Babin]

Is that AC or DC coupling? You need to use DC coupling. You also need to set the 'variable' to the cal position (fully clockwise).

You also need to post the settings for the vertical amp and timebase on the scope. In an earlier post, there was a '1' in the scope settings that you posted. I don't know what this was. If it was 1v, there is a real problem. If it was 1v but you're using a 10x probe, that would make more sense and the actual vertical amp setting would be 10v, not 1v.