I am late to this thread, but I found it very interesting. I am the third owner of my Acoustat 1+1 speakers. I purchased them from for only $350 from a friend that was very disappointed with the bass. I thought the sound was terrific and purchased them on the spot. Then I added a Vandersteen sub and invited him over. He was blown away by how they sounded.
Today, I run them with an active SPL crossover limiting the signal to the 1+1’s above 70 Hz with a steep -24 dB slope. The signal to the dual Rythmik F12SE subs is limited to below 70 Hz with the same -24dB slope. I keep wanting to get new speakers but have not found any that I prefer to this set up. I listened to the M35’s in Costa Mesa last summer and liked them, but felt they were lacking just a bit in bass oomph. I would personally add a pair of subs to them and have the crossover at around 50 Hz. But at $21k for the pair I won’t be making that test. Half that price, and I might be tempted. My speakers are around 35 years old.
Electrostatic speakers just have a presence that other speakers are missing. It is kind of like how some people love horn driven speakers (I don’t, but I appreciate them). They just sound different. Electrostatic speakers, in my space, makes me believe that I am in a mid sized live acoustic concert venue. It also helps that all my equipment was selected over the years to complement the 1+1’s.

