So, to be sure about which panels are dedicated to bass and to high frequencies, I am guessing the bass panels are at the top and bottom and the high freqency panels at the center. Is this so? And is there an actual xover for this? Thanks.
There are four panels in the 63/988. Top and bottom are bas panels. The two in the center with the concentric rings for time delat are fullrange.
Really? Can you point me to a link, because everything I have read on 63 says there is one diaphram and only one. This includes the Quad marketing spiel.
Hi,
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There are two panel types, two of each to make 4 in the 63/988.
The 989 has two additional bass panels top and bottom.
The diaphragms are individual for each panel.
rgds, sreten.
There are two panel types, two of each to make 4 in the 63/988.
The 989 has two additional bass panels top and bottom.
The diaphragms are individual for each panel.
rgds, sreten.
I've never taken one apart so will have to believe you, but why was it always described as a single full range diaphram (FRED in quad marketing terms). I see 4 stators but not 4 panels.
Hi,
The speaker is made of 4 modules, here is one module :
rgds, sreten.
The speaker is made of 4 modules, here is one module :
An externally hosted image should be here but it was not working when we last tested it.
rgds, sreten.
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Here a picture where you can see one panel being removed.
Here a panel.
There has been different panels too.
The joining of the various panels is a mechanicly weak point.
Here a panel.
There has been different panels too.
An externally hosted image should be here but it was not working when we last tested it.
The joining of the various panels is a mechanicly weak point.
ok, I see various stators. But is there one or multiple mylar diaphrams in there? Just trying to understand if I have a terminology problem or QUAD were being economical with the truth for the last 40 years!
Hi, Each module has its own diaphragm, rgds, sreten.
Its no different to clamping one large panel into areas.
Its no different to clamping one large panel into areas.
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Every single panel has its own diphragm. ESL 63/988 etc. are made up by four panels. The larger 989 has two more bass panels. In one of pictures you can see one panel being removed. That would not have possible with one single diaphragm.
The middle two panels contain 6 ring segments that are fed with a full range signal(not just high frequencies) using a lumped transmission line that delays the signal to each successive ring by about 20µS. After the 6th ring, the line is terminated in it characteristic impedance. The areas making up segment 7 are fed thru two 360Kohm resistors which form a first order low pass filter with the segment's capacitance, rolling off frequencies above about 3kHz. The top and bottom panels(and outer portions of the middle two panels) make up segment 8 which are fed thru two additional 360Kohm resistors. This adds another first order LP filter with roll off starting at about 500Hz. So, the top and bottom panels could be described as bass panels with a rather slow roll off coming from the two section R-C passive crossover.
However, at low frequencies all panels are active not just the top and bottom panels.
The middle two panels produce as much bass as the top and bottom "bass panels".
At higher frequencies, only the first 6 segments produce significant output.
Panel areas that make up segment 7 and 8 are labeled on the image sreten linked to.
Also attached is the detailed schematic and a simplified version showing how the segments are driven
Attachments
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Hi,
My esl-63 top panels are hissing and cracking. Guess I need to refurbish them. While at this, I'd rather fix the other bass panel, I guess. Can anyone recommend, a company that would do a decent job?
Thank you
Ran
My esl-63 top panels are hissing and cracking. Guess I need to refurbish them. While at this, I'd rather fix the other bass panel, I guess. Can anyone recommend, a company that would do a decent job?
Thank you
Ran
Sheldon Stokes on this site. (Stokessd)
If one is going you can bet the others are not far behind.
Plan on having all of them checked out
Regards
David
If one is going you can bet the others are not far behind.
Plan on having all of them checked out
Regards
David
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Thanks for the plug, David!
I am very willing to rebuild your panels, but I'm in the USA, so shipping will be somewhat expensive.
Sheldon
quadesl.com
I am very willing to rebuild your panels, but I'm in the USA, so shipping will be somewhat expensive.
Sheldon
quadesl.com
The "bass panels" also almost play fullrange to be honest. i measured them once and there is only a small rolloff but its above 10khz. but yeah top and bot usually are called hte bass panels: )
With my 2805 (same panels, different frame) it was not possible to remove the lower bass panel without first moving the next panel up. 63s may be easier, I wouldn't know.
it depends on what type of quad 63 it is, there are 2 kind of frames that i know of🙁