Comment about SS and Tubes

      The guys at Dahlquist designed the DQ-LP1 crossover, to mate a sub to their DQ-10 speakers.

       Being that their weren't a whole lot of self-powered subwoofers, back in the day; that little unit got a lot of application.

       I used one (variously upgraded) in my own systems, in concert with the 10" TL subs I built to go with my first pair of planars (Acoustat Mod III), for well over two decades.

       Looks like the JL crossover would be a good one, consistent with the quality of the rest of the OP's system.

       This article was of particular interest to me, as I've been using a TacT 2.2X for quite some time:

            https://www.whatsbestforum.com/threads/the-jl-audio-cr-1-analog-vs-tact-digital-crossover.19361/

         Roger Sanders was a youngster, when he wrote this article, for Speaker Builder (damn, I feel old):

               https://sanderssoundsystems.com/downloads/speaker_builder_dec_1980_an_electrostatic_speaker_system_Part%20III.pdf

          About that good old Dahlquist DQ-LP1, that I wish I still owned:

           https://sites.google.com/site/mpbarney/home/dahlquist-dq-lp1

@cinqcepages Wrote:

And I am super curious about bi-amping. As like SUPER

Actively bi-amping gives a reduction of intermodulation distortion. That said, active bi-amping horizontally, as I do, will give additional advantage from the elimination of lossy inductances in the LF portion of a conventional passive dividing network, and the result may be a significantly better amplifier damping factor, as seen by the LF driver. Active bi-amping is sometimes hard to implement, and the user is often left to his own devices. It should not be undertaken without first asking the manufacturer’s advice. IMO: Active bi-amping is two notches above a passive crossover. See articles below: Mike 😎

https://sound-au.com/biamp-vs-passive.htm

https://www.passlabs.com/legacy_products/xvr-1

I remember reading a long long time ago where an amp designer said his design was not just about the power at hand and being played but it was about the power on reserve to handle the demand when needed. He’s said the best test was the sound of cutting scissors snapping shut. It is a high volume very fast action that called for instant reserve power to reproduce the sound just right. Yes power is always nice but their is many many ways to incorporate it.

An SLP-05 with a good SS amp should work on most systems. 

@sgreg1    I agree about power in reserve.   The best (and possibly only) way to get it is to go Class A.

I don't have any recordings of scissors snapping shut.  Is there a test disc incorporating this?  Recorded using Telefunken U47?