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Quad 63 working when not powered

P

peelaaa

pfm Member
Hi. I have a pair of quad 63 esl. Haven't used them for 2 years. Powered them up today and one is emitting a high pitch whine. A bit like letting air out of a balloon.
Powered it down but it still gives audio out but at a reduced level.
If crackles a bit too when playing audio.

What can be done to fix this?
Thanks.
 
They will continue to produce music until the panels are discharged, this takes a few minutes if they are in good condition. High pitched whine sounds like it may be a fault in the EHT generation section. This is repairable, but you have to be electrically competent. There are very definitely lethal voltages inside these things.
 
The high voltage charge remains after switch off but will diminish in time so will get quieter.
The fizz noise is likely to be static discharge, possibly because it was stored somewhere a bit damp.
Put it somewhere warm and dry for a while so it can dry out completely and it may be Ok.
 
Thanks for quick responses. They were stored upstairs in a large cupboard off the bedroom. This area is bone dry and wouldn't be heated but wouldn't get that cold as it is between 2 heated rooms. Would putting a heater on for awhile help?
Looking from front of speaker the noise seems to be coming from right side about half way up.
 
Well it's possible but given that you say it was stored dry then Steve's answer may be more appropriate.
Well worth a try to get it warm and dry with the heater.
 
toprepairman said:
The high voltage charge remains after switch off but will diminish in time so will get quieter.
The fizz noise is likely to be static discharge, possibly because it was stored somewhere a bit damp.
Put it somewhere warm and dry for a while so it can dry out completely and it may be Ok.
Click to expand...

Thanks for quick responses. They were stored upstairs in a large cupboard off the bedroom. This area is bone dry and wouldn't be heated but wouldn't get that cold as it is between 2 heated rooms. Would putting a heater on for awhile help?
Looking from front of speaker the noise seems to be coming from right side about half way up.
 
Its surprising how little moisture they can take, a long stay in a cold unventilated space usually sees them needing a couple of days of warm and dry for them to start operating properly.

Dry em out, try again. Taking socks and dust covers off speeds up the process no end.
 
The noise has changed to a static crackle. Sounds a bit like heavy rain on a corrugated roof.
It's coming from top right panel. The red neon is flashing quickly in time with noise and some light flashing can be seen if looking closely.
Could this still be humidity?
 
Probably the glue in one of the stators has started to fail allowing the EHT to escape as the stator bends towards the diaphragm. If you're happy to take the socks and grilles off you may be able to see a discharge with the power on in a dark room.

People on here have had success doing micro-surgery on this failure (if that's what it is), a search of the Classic or DIY forums should reveal threads with pictures.
 
When I had to store my ESL57s for a few months in our (at the time unheated) barn, I left them powered up all the time, and they were fine. So, I think the best method for the moment is power them up in a warm dry place and see if they settle.
 
Been busy today.
I have disconnected the top 3 panels.
Powered up and the static is still there on the only panel that's connected which is lower bass one.
I am sure the lower panel was ok when all 4 panels are connected.
Meanwhile I dismantled the top panel and can see the mylar is torn on the right side. This is where the initial noise was from when I started this thread. Can this be repaired without replacing the mylar? Sellotape? Also I can see the stator board has come away at that end from the glue which probably burnt through the mylar. I'm guessing that the other panels must be torn too as there is still the noise when the top panel is not connected
 
The red light Indictates drop in charge, as does the ticking. Remove the bottom panel and refit the top one, if it still happens it's the eht boards or wiring, and it's unlikely to be wiring.

Check eht board for signs of overheating and wax melting off them. Servisol do an eht discharge spray that will replace any lost wax on an eht board. Servisol plastic seal 60.
 
peelaaa said:
Been busy today.
I have disconnected the top 3 panels.
Powered up and the static is still there on the only panel that's connected which is lower bass one.
I am sure the lower panel was ok when all 4 panels are connected.
If it's not the panels then what else causes this static noise? The eht unit? The red neon flickers at same speed as the noise pops.
Click to expand...
sq225917 said:
The red light Indictates drop in charge, as does the ticking. Remove the bottom panel and refit the top one, if it still happens it's the eht boards or wiring, and it's unlikely to be wiring.

Check eht board for signs of overheating and wax melting off them. Servisol do an eht discharge spray that will replace any lost wax on an eht board. Servisol plastic seal 60.
Click to expand...
Thanks. The top panel mylar is torn so that panel is now faulty. I'll get onto one thing audio for new panel.
 
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