RXV-3000 issues

[kikurass]

Hey guy's an gals, I'm new here, but have been in the AV field for years, I even worked on TV's and VCR's (Dinosaurs), anyway I have a Yam RXV-3000 that switches off as soon as you turn it on, this problem was at first intermitent, but now it just lights up, you here the first relay switch then nothing, no way no how will it remain on.

Now I understand that the relay is there so the amp can run diagnostics such as transistor checking, also a quick warm for them, speaker shorts ect.

Speaker shorts can be ruled out, I have not yet lifted the lid to inspect what may or may not be wrong, this being due to the fact that I had an early Yam amp the 900A series, it shut down a channel and I lost all manner of grey matter trying to resolve the issue, I never did, the security in place is astounding, and all loops back on each other, i just ended up trading it in.

So I am a little apprehensive about tearing this monster down.

Has anyone else had an issue similar to this?, if so would you be kind enough to at least give me a hint at what may be wrong.

I have not been a techy for 12 years, and feel somewhat left out when it comes to this sort of circuitry.

I bought this amp new, and until recently it performed flawlessly.
About 2 years after I bought it I listened to the RZ1, wasn't impressed for the extra $1500.00 they wanted after trade in. Without doubt this amp is the ducks guts, its only downfall (if you can call it that) is the bog stock prologic side of things, failing that I cannot fault it.

I run all Energy speakers inc the effects rears, and sub, my audio room is 40 feet by 30 feet and this sucker distorts the air so bad you cannot focus on the TV..............FUN!.

I live on 30 acres and my neighbor can hear me playing, I need to annoy him some more, so any help would be much appreciated.

Cheers kik.

 

[Nestor]

My guess is a power supply or an output capacitor has deteriorated, as the problem has gotten worse over time.

How old is the receiver?

 

[kikurass]

Rxv-3000

The amp is 5 years old now, but compared to whatever else is out there, from what I've seen and heard I want to hold onto her, some of the newer amps don't even have 8 channel stereo, which is a fantastic feature of the 3000.

5 years is a little young for caps to dry out, but on the other hand I paid $3500.00 for it and something somewhere is broke. Could be a good place to start.

Thanks for your input. kik

 

[kikurass]

Repaired.

I ended up pulling my amp down and checked a few items, one thing caught my eye from the get go, on the pre-amp module board the soldering was less then impressive, yet on the finals board the soldering was impeccable.

So I put on my loupre (eye's aren't what they used to be) and did a little dry joint searching, it took about a millisecond to find joint #1.

I ended up re-soldering the entire pre-amp board, my theory is that certain modules are farmed out to other firms/countries and the assembly is done there, as you would all probably know the pre-amp side of any amp is a simple set up, which is why I think this was done in China or Indonesia, doomed to fail due to inferior solder, and less of it, it is easier and less expensive to repair the pre-amp then the main amp or finals.

This would also explain Yamaha's drop in warranty longevity from 5 years down to 3.

For those that want to know, or have similar symptoms to my fault I have listed the main (high current) areas where the majority of dry joints occurred,
I also listed the failed components, so here is the list.

Please note all this is on the pre-amp module.
Q 362
IC 536
IC 353
IC 354
R 404
R 405
R 413
R 403
R 411

2SC-4512 transistor open.
Fortunately these are very common and I had a few new ones from when I was tech'ing, lucky for me it went open and not to a short, otherwise I would still be digging.

Finished by checking resistor variance, and for any leaking transistors.

All is good and it is kicking like a mule again. kik.