@thomask
I've enjoyed reading through your journey with the A7 and I think they sound fantastic in your YouTube clips, particularly the recent one with the speaker cable changes.
I recently bought a 'project' pair of Altec Valencias and I'm looking at upgrading the crossovers. Do you happen to know if there's a way to change the frequency range in the PAP C1 to lift the max to 800hz from 550hz? I've written to Nelson Pass on this but haven't heard back yet.
My other thoughts for the XO are to try the Lyngdorf that you mentioned, but it seemed to be a complicated arrangement. I owned a TDAi2200 some years ago and used it to run a set of Oris 150 stacked horns, with a Digi-out to a Tact digital amp for the bass towers, and it worked quite well. But I like my 300b monoblocks on the Valencias or the First Watt J2.
For subwoofers, I also have the Crown XLS2502 that you have and use a miniDSP 2x4HD to set the crossover points and add a little EQ, with the Crown powering a pair of passive subs (Aerial SW12 with plate amps removed). So I could try the miniDSP on the Valencias as a XO, but I've read it should only be done with measuring equipment to get the time alignment (phase) set properly between horn and woofer. Even though I have the UMIK-1 and REW software, I'm reluctant to start to mess with this, I'd prefer a more turnkey active solution if such a thing exists. It sounds like your c1 might be a solution if I can change that XO point.
Any tips would be most welcomed!!