long dead thread but Id like to breath new life into them. The ADS L7e and ADS B7 are super similar same drivers i belive xover design and box volume just the L7e is less utilitarian .. I digress, the point is this the 206-0122 tweeter is a Ferrofluid tweeter and I have found although not as old as some if they are left to sit to long the ferro fluid will give you a bit of low output on these tweeters (the 206-0122) is used in many other speakers as well (B7, B8, M9,, CM7, 6 , L7e 8e, 9e) C400i 750/ii M9/90, Sat 5,6,& 7) and i have found these super easy to replace ferrofluid on and some it made no difference but i had a pair of M9s and the higher end of the B7s sounded so much more "ADS" to me until i redid the ferro in the M9s .. and pop side to side low output gone