Pioneer amp cracking and scratching noises!! (1 Viewer)

[freddy400]

Hello
I have a very nice Pioneer VSX-859RDS amp which i have owned now for 6 months. I purchased it from ebay for a good price and up until now its been absolutely fine. Yesterday during a viewing session the amp started to make some horrible scratching and cracking noise for a few seconds then it stopped. At first I thought little of it then it suddenly got really loud and then it cut out. I jumped out of my sofa and tuned the amp off. i turned it on again and it was fine for a minute then it started again. Now it happens quite a bit. You may be able to watch 5 minutes of a film then it would start up again. Ive tried different cables and different sources but the same thing happens. Even if there are no sources plugged in it would do the same thing so it has to be amp. Any ideas would be very appreciated.
I don't think this would help but when i bought the amp they told me the radio was faulty (as in the radio doesn't pick up anything), I wouldn't have thought it would be anything to do with that. :frowning:

 

[Alex/d]

It's possible the logic board is bad.
It may not be, but my thought is that the radio portion had a problem, and wasn't affecting the rest of the reciever yet. However, over time, since the problem was still there, it started working it's way into the heart and soul of the reciever. (A shorting condition if you will.)

But the cracking noise, depending on what it is coming from...shorts can make that noise and do that to the reciever. (Case in point, bad transformer windings or a capacitor shorting to ground.)

Other than that... open it up and check for little critters. It sounds dumb... but just take a look anyways.

 

[Alex/d]

Also.. quoting this from Home Cinema Choice Review:
http://www.homecinemachoice.com/revi...VSX-859RDS.php


"Pioneer's VSX-859RDS did not have the most auspicious of starts. In January, the 859 and its sibling the 839 were recalled due to problematic power outputs, but those hiccups have now been ironed out, the 859 has passed HCC's technical tests and we're now able to fully audition what promises to be a highly attractive receiver."

"Internally, the Pioneer's standard of design is of the finest order, a model for all sub-£1,000 receivers to follow. The only downside is the cooling fan located between the power supplies and output stages, but it is used sparingly and you'll be hard pushed to detect its presence. On the left, a dedicated partition houses primary and secondary transformers. The output transistors are mounted along a centrally oriented heat sink, to the right of which, the sensitive DSP board lies within a completely shielded compartment, surrounded by tuner and analogue stages."


So by reading this.... it's VERY likely that one of these two are causing the problems, if not both.

The fan not working would cause the horrible scratching noise... but not so much crackling. However, a bad transformer (or anything with the high voltage side of the reciever) will cause that crackling noise.

 

[freddy400]

Thankyou very much for your response.
I played about with the amp for quite a while. Trying different things with the speakers. Some days it hardly worked at all and some not so bad. I left it running just the two speakers for a while and now after a couple of days ive had no problems. So im gonna see how it goes if it starts making those noises again I will take your advise and open it up and see what I can find
Thanks again!

 

[Alex/d]

No problem