Hi there
I hope that someone can help me to repair a faulty Quad ESL 63. The one speaker is making a sizling noise. I rebuilt all the panels and it was better, but still making a noise. I then swopped the transformer, EHT and clamping board assembly with the one from the other speaker. The fault moved to the other speaker. Obviously there is a fault on either the EHT or clamping board. I tested all the components and could not find any faulty components. Has anyone else come across this problem, and what was the solution? I suspect that the EHT is too high, but I cannot test it.
Thanks for the help.
Dirk
I hope that someone can help me to repair a faulty Quad ESL 63. The one speaker is making a sizling noise. I rebuilt all the panels and it was better, but still making a noise. I then swopped the transformer, EHT and clamping board assembly with the one from the other speaker. The fault moved to the other speaker. Obviously there is a fault on either the EHT or clamping board. I tested all the components and could not find any faulty components. Has anyone else come across this problem, and what was the solution? I suspect that the EHT is too high, but I cannot test it.
Thanks for the help.
Dirk
This might sound daft but have you contacted Quad to ask their advice yet at all? The last time I called was about a year ago, regarding a 33 pre-amp I was rebuilding, and they couldn't have been more helpful.
If you don't have it already, here's their contact details:
e-mail : info@quad-hifi.co.uk
Telephone (from UK) : 0845 458 1122
Telephone (international) : +44 1480 452561
Fax : +44 (0) 1480 413403
Post : Quad Service, Unit 4, St Margarets Way, Stukeley Meadows Industrial Estate, Huntingdon, Cambs PE29 6EB
A sizling ESL63 is Not Good News. You've clearly established that something EHT or claping-board-wise has decided to go pear-shaped, but exactly what is going to be tricky to ascertain. You say you've tested all the components and they seem fine, and as you clearly know what you're doing, I reckon that you're on the right lines in thinking that the EHT is set too high. Testing this is going to be fun, especially as you don't want to risk frying anything. If Quad can't help over the phone (which would surprise me, frankly), then I suspect this might be the time to bite the bullet, blow the savings and take advantage of their legendary service department rebuilds. It's not cheap, but it represents good value -you'd in effect have a brand new pair of ELS63s at the end of it.
Good luck & all the best
Scott
If you don't have it already, here's their contact details:
e-mail : info@quad-hifi.co.uk
Telephone (from UK) : 0845 458 1122
Telephone (international) : +44 1480 452561
Fax : +44 (0) 1480 413403
Post : Quad Service, Unit 4, St Margarets Way, Stukeley Meadows Industrial Estate, Huntingdon, Cambs PE29 6EB
A sizling ESL63 is Not Good News. You've clearly established that something EHT or claping-board-wise has decided to go pear-shaped, but exactly what is going to be tricky to ascertain. You say you've tested all the components and they seem fine, and as you clearly know what you're doing, I reckon that you're on the right lines in thinking that the EHT is set too high. Testing this is going to be fun, especially as you don't want to risk frying anything. If Quad can't help over the phone (which would surprise me, frankly), then I suspect this might be the time to bite the bullet, blow the savings and take advantage of their legendary service department rebuilds. It's not cheap, but it represents good value -you'd in effect have a brand new pair of ELS63s at the end of it.
Good luck & all the best
Scott
Thanks Scott
I will contact them. Anyone else that have had any experience fixing ESL 63's perhaps?
Dirk
I will contact them. Anyone else that have had any experience fixing ESL 63's perhaps?
Dirk
I have had some experience with ESL-63s.
Since your problem seems to be in the electronics, we'll ignore the usual reasons for drivers to hiss.
One thing I found about the wiring is that Quad used the absolute cheapest, crappiest wire they could find- I think it was made by the same company that makes all those electronic parts they sell at radio shack that have solder lugs that solder won't stick to. Anyway, they used solid core wire that breaks easily. You need to make sure that a ground wire hasn't broken off one of the many lugs that connect the audio transformers and HV supply to the metal "chassis" in the electronics box.
I was rebuilding an ESL 63 and had exactly that problem and the result was a very hissy speaker with very low output. It took a lot of careful inspection to locate the problem.
Also, check the routing of the coiled wire from the bias supply board to the connection to the speaker. The insulation is thin and if it gets too close to ground or any other part of the speaker it will cause hiss. While you're at it, check the connections that use the very stiff, thickly insulated HV wire. The wire is easy to break at the solder joints by flexing or repositioning a few times.
Finally, if none of that yields a solution, try turning out the lights and look for blue sparks. Where there is hiss, there are sparks.
The bias supply voltage is fixed by the transformer and voltage multiplier board. There is no setting other than switching the primary voltage at the input. Make sure the switch is set correctly (duh!). There is no other way the voltage could have risen, unless you added mucho capacitance to the bias supply board. The thing worked fine at the factory with full bias voltage and should continue to do so, as does your other speaker.
I_F
Since your problem seems to be in the electronics, we'll ignore the usual reasons for drivers to hiss.
One thing I found about the wiring is that Quad used the absolute cheapest, crappiest wire they could find- I think it was made by the same company that makes all those electronic parts they sell at radio shack that have solder lugs that solder won't stick to. Anyway, they used solid core wire that breaks easily. You need to make sure that a ground wire hasn't broken off one of the many lugs that connect the audio transformers and HV supply to the metal "chassis" in the electronics box.
I was rebuilding an ESL 63 and had exactly that problem and the result was a very hissy speaker with very low output. It took a lot of careful inspection to locate the problem.
Also, check the routing of the coiled wire from the bias supply board to the connection to the speaker. The insulation is thin and if it gets too close to ground or any other part of the speaker it will cause hiss. While you're at it, check the connections that use the very stiff, thickly insulated HV wire. The wire is easy to break at the solder joints by flexing or repositioning a few times.
Finally, if none of that yields a solution, try turning out the lights and look for blue sparks. Where there is hiss, there are sparks.
The bias supply voltage is fixed by the transformer and voltage multiplier board. There is no setting other than switching the primary voltage at the input. Make sure the switch is set correctly (duh!). There is no other way the voltage could have risen, unless you added mucho capacitance to the bias supply board. The thing worked fine at the factory with full bias voltage and should continue to do so, as does your other speaker.
I_F
Dirk, I_F has a pile of good suggestions. I would be inclined to just go in and replace all the diodes and caps in the HV supply. They tend to go leaky over time and that can cause exactly the symptoms you describe. Worst case, it won't fix things and you're only out a few rand. Best case is that it does work and you've saved a pile.
BTW, Paarl is a GREAT town. Love the place.
BTW, Paarl is a GREAT town. Love the place.
A step by step procedure on diagnosing the QUAD ESL63
Dirk,
Check out my web site for a step by step procedure on diagnosing the QUAD ESL63 loudspeaker.
The URL is http://www.geocities.com/quad_esl63/
Dirk,
Check out my web site for a step by step procedure on diagnosing the QUAD ESL63 loudspeaker.
The URL is http://www.geocities.com/quad_esl63/
Hello;
IMHO it is impossible that any component of the clamp circuit causes the "typical" sizzling noise (sizzling = speaker makes noise WITHOUT any audio being applied).
If any of the caps or diodes on the HV supply board becomes weak, this will cause the HV to go down from the regular value of 5,2 to 5,4 KV to 2 KV or less. Which means it is very unlikely to achieve a corona type effect from a faulty HV supply with even less voltage.
One question should be most interesting: Where does the noise come from (which area of the speaker?).
I fear you still have a panel problem (even if it doesn`t seem so because the failure "moved" when changing electronics).
regards, audiomatic
IMHO it is impossible that any component of the clamp circuit causes the "typical" sizzling noise (sizzling = speaker makes noise WITHOUT any audio being applied).
If any of the caps or diodes on the HV supply board becomes weak, this will cause the HV to go down from the regular value of 5,2 to 5,4 KV to 2 KV or less. Which means it is very unlikely to achieve a corona type effect from a faulty HV supply with even less voltage.
One question should be most interesting: Where does the noise come from (which area of the speaker?).
I fear you still have a panel problem (even if it doesn`t seem so because the failure "moved" when changing electronics).
regards, audiomatic
Hi there
Thanks for all the input from everyone. I tried to short out the one cap on the HT board that I suspect to be faulty, and it actually cured the problem, having obviously reduced the HT voltage somewhat. I have never come accross any references to an HT board putting out to high a voltage, but in my opinion it has happened in this case. Any suggestions?
Regards
Dirk
Thanks for all the input from everyone. I tried to short out the one cap on the HT board that I suspect to be faulty, and it actually cured the problem, having obviously reduced the HT voltage somewhat. I have never come accross any references to an HT board putting out to high a voltage, but in my opinion it has happened in this case. Any suggestions?
Regards
Dirk
I don't see a mechanism for the EHT board failing high. But nevermind.
I'd recommend you measuring the voltages, something like the http://www.testec.de/prod12.html will do the trick. Or perhaps a local technician has something. A device for measuring colour TV EHT levels might be suitable.
Paul
I'd recommend you measuring the voltages, something like the http://www.testec.de/prod12.html will do the trick. Or perhaps a local technician has something. A device for measuring colour TV EHT levels might be suitable.
Paul
DirkD said:
Lowering the bias supply voltage is putting a bandage on the problem, not curing it. It is like fixing a flat tire by letting the air out of your other tires so they all match.
The voltage wasn't too high- there is no failure in the bias supply that can make the voltage increase. What you did was lower the voltage to the point where you no longer get the corona discharge or arcing, whichever was responsible for the hiss.
If you are satisfied with the performance of the speaker with reduced bias voltage, there is no reason not not to leave it that way, unless its output is now lower than the output of the other channel (probably), but that's what balance controls are for...
I_F
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