Sealed subwoofer for ESL-63


I am looking for owners who have successfully integrated their QUAD ESL 63s with a subwoofer.

I recently bought a used pair of QUAD ESL63 and had them rebuilt, panels and electronics, this is my third pair. I have had several monkey boxes in between - Aerial 10T, B&W, KEF, IMF, Tannoys, Proac, Goldmund, Falcon Acoustics kits, etc - but the 63s are very hard to live without when you know what they can do.

My problem is that I am particularly fond of large-scale symphonic works such as Wagner’s The Ring , Beethoven, Mahler, Strauss, etc. but the 63s are very special and very frustrating used full range, they have limited bass and dynamics.

I am retired now and have a fixed income so I cannot keep doing what I did for fifty years, buy, experiment, trade and sell.

I would like to keep the cost of the sub to $1K max for a good condition, one owner unit.

Best regards,

f456gt
Buy a Martin Logan Sub. After all they build Electrostatic speaker. I use one Depthi-i sub with excellent results with Crossover at 35. Seamlessly blends in and makes my 63 sound even better but without hurting the mid range purity.
I have Quad 2805s, and added a B&W PV1d because it was claimed to be very fast and easy to integrate with the stats. The result was disappointing, even in my large listening room. The combination sounded boomy unless I reduced the level to a point where I could not quite hear the sub anymore. All this was largely solved when I added an Antimode 8033 room equalizer for the sub. The bass now integrates perfectly with the stats.
However, Duke is also right that multiple subs are another way to address this, and over a wider area (his Swarm system seems a very good way to do this), so I will buy at least a second PV1d (not sure I can persuade my wife to live with more than that - and quite rightly so), still combined with the Antimode (and one sub with inverted phase).
Just to add: I cross over at 33 Hz and a 4th order slope. The advantage of the PV1d is that you can set crossover very precisely, and also choose between 2nd order and 4th order slope. I think it is important that you can cross over at a low enough frequency: even one or two Hz higher sounded a bit smeared in my case.
My advice would be to go for two small subs rather than one larger one, and include an Antimode 8033.