Parasound HCA2200II Troubleshooting

[jsleonardo]

Hi diyAudio,

I have Parasound HCA2200II and recently had issues that started with the cracking sound on Right Channel. I removed any speaker due to high probability of damaging the speaker.
When I am verifying the schematic which I have, I found that the R225 is measuring 20K ohms instead of 47K.
Bias resistors are railed voltage at +/-77V on the Right Channel while Left is around 25mV.

I am inclining that there is/are bad components on the driver board.

I also noticed sparkling on the R217 on the PCB trace when powered-up but this is gone now. I've checked the Q201-202 and Q203, they looked okay when compared with Left Channel.

I am attaching the schematic I found in the web.

Thank you in advance for the help.

 

[huggygood]

I also noticed sparkling on the R217 on the PCB trace when powered-up but this is gone now.

🤔

 

[bergui45]

Sorry but your schematic is for 1200 instead of 2200!?

 

[Pars]

Here is the schematic for the 2200II

 

[bergui45]

Wahouh! Thanx a lot...
But my HCA-2200 is an mk2... Is your schematic for the 2200II only?
Only the latest HCA-2200mk2 has been designed by John Curl... So obviously i need a specific schematic for the mk2 model...

 

[bergui45]

OK your provided schematic HCA-2200II is the good one for the mk2!

 

[Pars]

Not clear whether the 2200II and a mk2 are the same thing. I suspect they are, but not sure (never owned these)
Parasounds' web site says the 2200II was designed by John Curl.

 

[bergui45]

OK! For me 2200II = 2200mk2!
;-)