Aurum Cantus AC-130MKII 5-1/4" Carbon Fiber/Kevlar Woofer

I just installed the Aurum CantusAC-130MKII 5-1/4" Carbon Fiber/Kevlar Woofers along with a new silk dome tweeter into my old Infinity 2001 bookshelf speakers. I used the factory crossovers that are set at 4700 but I may experiment with a lower frequency.
I also lined the relatively small enclosures with foam and added a little poly stuffing. Wow, they sound huge. Very clear throughout the entire spectrum. Great bottom end for such a small speaker!

I bought a pair of infinity SL10 which needed woofer
Replacement.I also own Bower and Wilkins all over my basement and this speaker has a similar woofer just like my other speakers.I strongly recommend this speaker for a replacement woofer.

I am using these in a (dipolar) MTM configuration with the AC G3Si ribbon tweeter.
I am using an active crossover (nothing fancy, a dbx 223xl)and a Rogue Atlas 50wpc EL-34 amp for these drivers. Based purely on listening I have ended up with xover points of about 70Hz and 5.5Khz. I agree with the other customer's comment that these guys can't go much higher up without becoming "shouty". WARNING: These drivers sound awful right out of the box (as do most really good ones!) but after a week of use they are already getting a bit "warmer and rounder". I know from prior experience with this brand that run-in time tends to be long....so I am optimistic that in a month or two they will be fully "oriented". These mid/woofers have excellent dynamic snap...plucked acoustic guitar strings explode from the speakers. Their micro-detail portrayal is also very good, with plenty of low-level information resolved. I cannot speak to their LF performance since I am not feeding them a low bass signal, and since my chosen dipole operation would kill any bass fed to them. At the sale price I paid for these last year (about $45) they are an excellent value. In my dipole MTM application as a midrange, these sound excellent, with exceptionally low distortion.