Thank you for the gentle replies! I can do a "core" exchange through Vandersteen direct. That would cost slightly more than a Behringer NX3000D amp. The Vandersteen 2W is, as everyone states, "long it the tooth" Even Vandersteen commented to that.
So an external amp allows future flexibility with other passive subwoofers. But even that has become a difficult comparison for me.
Behringer NX3000D has ostensible advantage of DSP
Vs.
1. RBH SA-500DSP (500W x 1Ch 4 ohms) - Subsonic Filter from 16Hz to 40Hz in increments of 1dB (16Hz, 17Hz, 18Hz, etc.).
2. Yamaha PX3 (500W x 2Ch 4 ohms ) - Subsonic Filter down to 20Hz.
3. Dayton SA1000 (1000W x 1Ch 4 ohms) - Subsonic Filter Fixed at 18Hz.
4. Klipsch RSA500 (300 watts continuous into 8 ohms or 500 watts continuous into 4 ohms)
LOW PASS CROSSOVER Continuously variable from 40-120Hz, designed for Klipsch subs.
With a gun to your head, which one? I'm sure I'm overthinking this...
Thanks again Genius Network!