Don't know about the 1Ci but the 2Ce Sig II has the 3A Sig tweeter (also, same as original Quattro). See here: https://www.audiocircle.com/index.php?PHPSESSID=38u42p6hcui5ssvle2oafc8s43&topic=100766.msg10174...
For the money, I haven't heard anything better than the 2Ce Sig II. Latest production using the woven midrange from the 5A.
I drove the 2s to satisfying levels in my 18x19 room (vaulted ceiling) with an Ayre AX-7 (60W/8 ohm) altho the amp would clip if I really pushed it (I don't likes peaks more than 85-90 dB, so not an issue for me).
For the money, I haven't heard anything better than the 2Ce Sig II. Latest production using the woven midrange from the 5A.
I drove the 2s to satisfying levels in my 18x19 room (vaulted ceiling) with an Ayre AX-7 (60W/8 ohm) altho the amp would clip if I really pushed it (I don't likes peaks more than 85-90 dB, so not an issue for me).