Rotel RB985 hum/ buzz

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BobsYourUncle

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Ok, so what I have done is bought 4 massive capacitors 15 000MFD /100v with screw terminals.
I figured that this would be ok because since the centre channel was a waste and never going to get used , I removed it. I Figured , that it was either I take a loss on this or tailor it a bit to suite my needs. There was no ways that I was going to spend another R2000.00 on this after already spending R1100.00 getting in those caps from eBay which I will never do again.The centre channel is of no use to me and I will use front and rear channels to bi amp my speakers.

Problem 1
I noticed 2 ground wires that run across all 3 amplifier boards.

One that goes across the negative on the line inputs and another that I can trance to the ground connection of the transformer output.

When the ground that goes across line input ground is not connected to anything, the amp goes into protect mode so I grounded it along with the other ground on the ground output of the transformer. I now have a 50hz hum and a buzz. From what I can tell is that nothing is grounded to the case of the amp when measuring with a meter. Looks like the centre channel amplifier did have a point where it could ground but on the board there was no components to join that grounding point to the rest of the circuit.

Problem 2
before I did anything to this amp, the right hand channel runs warmer than the left. It was softer than the left before the capacitor change but now gives out what appears to be the same volume, still runs warmer.

The amp sounds better than it sounded now when I got it but that buzz and hum bugs me. What also happens is that the transformer now hums a bit when the stove or the iro0n is tuned on. It never did this before , its not a constant hum but varies , almost like a slow pulse if that makes sense.

Pics below to show where I have grounded it and what I have done. Its not the finished product yet as I need to neaten wiring a bit and make a new plate to hold the capacitors. I messed this one up when doing the bends and drilling the one hole to mount the caps when making the plate from a piece of aluminium. The capacitors are not ideal but we had got them and they were the right value but the voltage a bit higher. They are Alcon PG-6DI-AESTD 15K100

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