German
version (expected soon)
French
version (expected soon)
One Thing Audio
Quad
General: notes on the ESL 63
Notes applying to the ESL 57 apply, in the main, to the ESL 63, although the 'differences' are significant. Although the 'running-in' time for new or rebuilt panels is similar, charge-up is instantaneous (a feature of all metalised diaphragms). This means that panel defects will be obvious as soon as mains polarising voltage is applied - clicks, pops, hums, fizzles or alarming 'tearing' noises are indicative of' diaphragm or electrode collapse. Unlike the 57 bass panel (which has a similar polarising voltage) the 63 panel has precious little electrode insulation (in order to assist high frequency radiation) thus the panel can be pretty volatile in 'letting you know' that something is wrong: Occasionally misguided owners attempt to 'repair' damaged or floppy membranes by the crudest of means - contact adhesive, sellotape etc. Such 'patching-up' jobs are doomed to failure. Despite this, the average life of a 63 panel used in correct conditions is around 20 years - only the best of cone drivers will equal this. Moreover, the range and diversity of cone drivers means that few are likely to be replaceable in 20 years' time, whereas the 63 (and its 988/989 derivative) will, in all probability, go on indefinitely.
With the introduction of the 988/989, the hugely successful ESL 63 is being 'reassessed' in some quarters and already shows signs of acquiring the 'classic' status currently reserved for the ESL 57. It is, in our humble opinion, still the most remarkable and ingenious loudspeaker ever designed, and by far the most 'accurate', even though 'purists' constantly moan about its complexity (we haven't seen many Krell amps which are 'a-straight-piece-of'-wire-with-gain' either.)
One Thing Audio produces a significant number of replacement spares for the ESL 63 (see price list;) and at the time of writing a full range of electrical spares are readily available directly from Quad. Sadly, Quad's current resource and rationalisation policy has put paid to most of the speaker's constructional hardware, so all you dedicated DIY ers - don't wander too far away, you may well be conscripted yet again!
