Olle from Sweden has sent in some pictures and a description of his Quad 63 rebuild.

Experiences from repairing a pair of Quad ESL63 speakers during 2021.

I bought the speakers second hand in 2008 from a seller in Sweden. They were transported by bus as goods so the grills were a bit dented on arrival. With only power applied but without music there were clicks, pops or hiss present. With music they appeared to have very different sound levels. What to do? I put them in storage for the time being and there they were until this year 2021.

I am now retired and have plenty of time and no pressure to work fast during evenings and weekends. What a bliss!

I have searched the net for ideas on how to repair these speakers. I found some projects with lots of pictures and descriptions but also, as I imagined, lots of gaps. I found a few sellers of materials to be used during a repair. But what did I need? How much? How actually do I perform the repair? …..

So in October I found Rob's Quad ESL 63 repair kit including instructions. I bought a kit and waited patiently for the package to arrive during these difficult Corona times.

While waiting for the package to arrive I read the instructions document that Rob sent by email. I read it several times, carefully, as it contains much information, tips and hints. I also had time to prepare a workspace and buy a few items locally, as masking tape and Sugar Soap.

I spent several weeks working on the speakers. I worked deliberately slowly as it was exciting and fun. The gluing operations cured extra long time to be ensure correct results. I removed and replaced seven diaphragms, re-glued two stators completely and enhanced the glue between stator and matrix on all remaining panels. Clips were added to the long sides of the black panels. Both high voltage boards needed attention. Both voltage regulator circuits had a too high output voltage. The input bi-polar capacitor was replaced with an ELNA RFS audio grade electrolytic bi-polar capacitor.

I ran into some problems during the repair. I corresponded with Rob using email and always got solid and good advice how to solve or overcome my problems.

So finally the repair was done. The speakers were powered up and ready to play. No clicks, pops or hiss were present.

The sound was very clear and detailed, maybe a bit harsh. The bass was surprisingly solid and deep. Over the days the sound has now matured and the treble is still very clear and detailed and now also completely smooth without any harshness.

I find the repair kit very easy to work with and well worth the investment. The support from Rob over email is a comfort and a great help. I can recommend this kit for any handy person interested in restoring their speakers to a new life.

Malmö, Sweden, December 2021.



Olle has provided some photographs of the repair process, he has also provided a useful tip for those who have the earlier black panels with smaller cell size. More detail of this will be included in our Quad 63 to 2905 repair kit manual.

Olle 1
Olle 2
Olle 5
olle 3
olle 4

Above, front view of one of Olle’s speakers before any work is carried out. Note, one of the mid / treble panels has been replaced with a later version. While this will work it is not ideal because there is a slight difference in the early annular rings compared to the later version. Ideally 2 panels of the same type should be used. The bass panels are interchangeable and can be mixed in any order.

The following note is a snip from Quad’s service manual.

Element change

Above, rear view of the speaker under repair. Below, as well as loose stators some panels had torn diaphragms and holes in the diaphragm caused by stator to stator arcing - this indicates a potential problem with the protection circuit.

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