Harman Kardon HS250 , Low volume problem.

[Moreno83]

Hey guys ,

A friend of mine asked to take a look at his harman kardon set. It turns on fine but the volume is very low on max settings. It goes max to 0DB but the volume is low.

I replaced all capacitors in the powersupply section except for 1. A 2200uf/25v , dont have that 1 anymore. Could replace it for 3300uf , no room for 2 caps in series.
There is absolutely no difference in volume after replacing the caps.

Anyone familiar with these models? Im suspecting one of the diode's.....

[Moreno83]

Re: Harman Kardon HS250 , Low volume problem.

I will buy some freeze spray and freeze the diode's. See if it changes anything.

[R_J]

Re: Harman Kardon HS250 , Low volume problem.

Why don't you start by getting the service manual. Have you tried a processor reset or master reset? were any of the caps you replaced bad?
I had a quick look in the manual and there are a few modes that might result in no/low audio ir the system is in pause mode or slow motion

[Moreno83]

Re: Harman Kardon HS250 , Low volume problem.

Thanks for the reply. I already checked the service manual for a quick solution. Reset did not fix the problem and i can't change much in the menu settings.

Yes some caps did not look good but the brand is Capxon which is not good at all so i decided to replace them all.

[Andrew F. Ali]

Re: Harman Kardon HS250 , Low volume problem.

Low output without distortion could mean low voltage from the PSU if it affects both channels. If you have low volume with distortion I would suspect faulty output ics and /or driver transistors/ ics.

[Moreno83]

Re: Harman Kardon HS250 , Low volume problem.

There is no distortion , just low volume. Like 20% out of 100%.

[Andrew F. Ali]

Re: Harman Kardon HS250 , Low volume problem.

You may have low voltage coming out of the PSU like a weak capacitor, open resistor, weak regular component or a faulty IC/transistor in the pre-amp stage.

[CapLeaker]

Re: Harman Kardon HS250 , Low volume problem.

The only thing that I may add is the over temp circuit. It will limit the PA output. How is the sound through the headphone jack? Attached see the service manual.