Harmon Kardon amp no sound on some channels? need advice please

[mzone]

hi there,

i bought a AVR 507 off my mate who got it off a friend who said it was not working properly,

the left and right channels are not working, however the sorround left and right are ok,

i was thinking of putting this in for repair, however are these amps expensive to repair? does it sound a expensive fault? being ive never owned a Harmon Kardon amp before i dont know, is it even worth paying to get it repaired, or should i just stick to my sony db940 dolby digital map?

many thanks

[opelrsx]

hi there,

i bought a AVR 507 off my mate who got it off a friend who said it was not working properly,

the left and right channels are not working, however the sorround left and right are ok,

i was thinking of putting this in for repair, however are these amps expensive to repair? does it sound a expensive fault? being ive never owned a Harmon Kardon amp before i dont know, is it even worth paying to get it repaired, or should i just stick to my sony db940 dolby digital map?

many thanks

I have the same problem.. center and surround are not working.. sent it back to factory for repair yesterday, luckily I still have warranty, don't know how much it costs.. I was told that problem is some kinda chips, no clue though, I know nothing about receiver :roll:

[mzone]

did you get your amp fixed mate?? did you find out what the problem was?



im gutted as:

i have also got protection mode on my harman kardon avr507 amp,

really cheesed off!!

my front left & right was not working but my surround left and right was as well as center channels,

thought id take it into this tv repair shop, he said it would cost about 90 pounds to repair, i thought ok what the hell least it will be all done,

waited 5 days and phoned, he said good news and bad news :/

i asked whats that then,

he replyed" good news is the front left and right are working now,
bad news
he replyed" the left surround is not working.

then he said" i replaced the blown transitors, however the left surround channel, its ok for about 5 mins, but then gets red hot and keeps blowing the transistor,
he then replyed" only thing i can suggest is to see how it goes for 3 months and if its still ok bring it back and i will try and fix the left surround :/

now is it me or dident i not put this in for repair??? dident he say it would be 90 pounds to repair it? i dident think repairing a amp mean half repairing it??
i think either he couldent be bothered or wasent experenced enough for the job, as that come back in 3 months sounds like a fob off to me what you guys think?


also, whats strikes me strange is, my surrounds were ok before it went in but my fronts was not, now only 1 channel on the surround works, and the 2 fronts are working?

protect only comes on if i plug a speaker into left surround.

im very unhappy as its still not fixed :/

what do u guys make of this?

[mzone]

did they fix it? did they say what chips?? were gone?

[Kevin Allan]

Hi mzone,

I just had my HK AVR65 in for the very same reason (center & LF channels dead). My warranty ran out years ago, but took it into a reputable repair shop that I had delt with, and happens to be the HK depot. In less than a week I had it back home and working better than before.

All that was found was a 1/4 watt resistor in the preamp section of each channel was toasted. Asked why and could not get any answer, but the amp, I swear, has about 10% more dynamics. The other thing replaced was a regulator (transistor in the power supply section) that was weak and would cause me grief in the future. The total cost, including a good cleaning (dust inside the cabinet) was $160 Cnd.

From what I know of the HK line is that your amp is very similar to mine in the output sections, and possibly the same problem/cure. How well do you know the service business reliability? I am suspecting that you've been charged a lot if it is the same problem. By the way, I believe my problem was caused by static and I gave the unit some zap.

Anyway, I hope you make out OK. Cheers.

[Kevin Allan]

I think, in hindsight I was being pretty general in my assumption as to the possible problem with your HK. There are of course many things that could go wrong and just wanted to relay what I had gone through.

What you may wish to try is confirm your connectors/wiring/speakers are not the cause. Change around the speakers to confirm. If no luck, and you have pre-amp outputs, hook-up an amp to these pre-outs. This will elliminate the amplifier section, and confirm problem in pre-amp section. If, like my situation, you have no signal from your pre-outs, then you can be pretty sure that is where your problem is. This worked well for me, as when I took the HK in to the service center, I was able to explain confidently where the suspected problem was. I was told on return of the unit that the weak regulator was influencing circut voltages slightly, and may well have contributed to the problem, and the resulting difference in the "soundstage" dynamics I spoke of. No kidding, I had to increase my sub output by about 10% to be on par with the surround mode balance. Required less volume for the same "percieved" output.

Anyway, post your results/repair for us. These things are helpful to everyone.

Kevin