KEL84 noise in left channel

[Riggers]

Hi
I would second Snowman’s advice re poor solder joints. I had an infuriating noise in my WD88 similar to what you described which in the end was a poor solder joint that to the naked eye looked fine. Use a wooden chopstick when powered up to carefully prod joints or alternatively when NOT powered up pull at any wire to pcb or solder tag connections and check for looseness.

Worse case remelt all solder connections.

Cheers
Phil.

[YummyFuzz]

Thought I'd post a follow up.
Indeed, after chopsticking arround it was the sockets that I had placed on the wires to the speaker terminals, and after just soldering those it is much more well behaved. Thanks for the advice.

[simcox1]

I'v had a similar issue with my kel84, rustling noise on the right channel. It hasn't done it recently. But I'm pretty sure it's due to some poorly soldered joints, on my part.

[Richard]

Good that you fixed it!

Sometimes you can carefully flex the pcb with a stick at a certain point and hear the sound change. You may not find the exact joint so re-solder a dozen or so around the area.

Valve sockets can be a problem on pcbs. Fit an old valve and resolder around the base. This lets the floating pins inside the socket align to the valve pins.

Thick items like sockets, terminals, and bus bars may need a little extra heat so pre-tin them, then use a little fresh solder on the iron and hold the iron an extra second whilst applying fluxed solder and watching that it flows onto both parts.

Apply iron and solder to the thickest part first, if it's a component leg into a pcb apply it to the leg then once it's flowing move the solder down to the pcb pad which will fill instantly.

Here's a pic of my favourite dry joint, a twisted wire onto a greasy bus bar which metered at several ohms, held mostly by the flux