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...
grateful

Showing 4 responses by tsushima1

Howdy folks .

I have recently acquired a pair of ESL-989's and whilst mugging up on user tips and tweaks I came across this most informative series of posts, amongst others, recommending a number of modifications ,chiefly the replacement of the 220uf lytic with metallised or film/foil poly + associated resistor.

I was under the impretion that those componants would be reasonably easy to get at ala the 63's however I was kinda dismayed to see the components connected directly to the PCB

I'm pretty good with point to point circuitry however I tend to shy away from PCB work .

I would be grateful for any further tips regarding the safe removal of the 220uf + R15 together with any further info re securing the replacement polypropylenes into the circuit .
Any under the hood images post modification would be most appreciated.

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 !
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.

My apologies for the Tardy Reply gents , I have only just returned to this project and thread.

Terry9 and MKsj2 , Thank you kindly for your assistance, I have emailed you both .Likewise Grateful , just off to admire your system.