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Quad ESL Cap mods

Hello,
I have a pair of Quad 988 I'm considering replacing the electrolytic 220uF Capacitor for a film cap...

For those who have done it -- what caps give you the clearest extensions in the highs and improved mids without mudding the low???

Also, who makes a 220uF film cap? All I seem to find is lower values? Is it best to wire a bunch of lower value caps together for a total 220uF (if so, should you mix electrolytic caps with film caps - like some modders do) or is it best to have a single 220uF cap?

I do see Mundorf has 200+uF caps in their Tube Cap line -- are these Mundorf Tube Caps appropriate for the Quad ESL application? how do they sound?

Thank you guys very much for any and all input into this, as I'm just beginning my Quad mod journey...
128x128grateful
johnsonwu
469 posts
 
The PCB is one sided, so you will need to carefully unscrew the mounting screws and flip it around and unsolder the orginal sand resistor and lytic.
You will need special nylon tie wraps to tie the new (HUGE) lytic and bolt the tie wrap onto the large screw that the panel is mounted onto the base.
You will need to use some 16 to 14 gauge wire to extend the leads of the cap to reach the appropriate connection points.
tsushima1
1,165 posts
 
Thank you for the further information Johnsonwu.

I was also considering replacing the internal 220uf/1.5ohm with a section of wire to complete the circuit, placing the components in a separate box outside the base , connected via additional RCA's ~ Speaker cables > box > 989 speaker binding posts.

That way I could utilize several or large size Poly caps that would be difficult to shoe horn into the space available in the base!

Feasable Folks ? or a little Heath Robinson !
johnsonwu
469 posts
 
YOu can still use several AXON 250 90uF available for cheap @ Partsconnexion if you dont want a single cap.
SPend some $$$ on resistors, the cap does a lot but its not the be all end all to the mod.
Placing them outside the box may involve drilling which WILL make the speakers unsellable.
I'd think twice about it.
I can dig up some old pictures of how mine looked like after the mod and send it to you.
It might take me a few days to find them though.
tsushima1
1,165 posts
 
Thank you once again Johnsonwu for your advice.
I would be very interested in viewing any Post Surgery images that you might dig out, most kind.

johnsonwu
469 posts
 
Sadly I could not find any photos of the inside showing how I mounted the cap. I remember I took a bunch of them but I could not find them anywhere now. Mine were sold in Sept.
Take a picture of yours and I can guide you on how to easily mount them.
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