Subwoofer Question s

OK, this topic is related to a question I asked some time ago. Another answer to this situation is the Classe CP 800 preamp. It outputs for two channel setups like yours. It has an internal crossover. I own one. I use it on my Snell Type A V 5's which consist of two tower (38 htz to 20,000 htz) and two 18" bass units. Normally the system came with outboard active crossovers which are RCA only. I wanted better so I bought a Marchand crossover for splitting the signal. The bass was to die for but the upper frequencies lacked something. I thought that removing the Marchand unit might do the trick as I'd have a shorter signal path and fewer cables. The midrange and treble are now incredible with the Classe but the bass is now lazy. I used to be able to shake the walls if I wanted to. No can do now. I need to try a few more things. Does anyone know about the differences between LFE processing and an active crossover? Maybe the answer to audio bliss lies in unraveling this mystery. Joe

Hello, I apologize for taking so long to respond back to you Bob Reynolds. My Dad is in and out of the hospital and my time is limited to family these days.
I had an hour yesterday so I played with the settings on the CP800 AGAIN. To back it up a bit, here is my setup:
Snell Type A V5- This consists of two towers(4 mid woofer and two midrange and one tweeter)and 2 18 inch subwoofers. My CD player is a Cary 306. I'm using a Classe
CA2200 amp and a Parasound 2100 on the bottom end. Previously, I used a Pass Labs preamp that I ran to a Marchand crossover. I use several brands of high end cable. With the Pass and the Marchand, the bass was to die for! If I wanted to crank it a little, I could shake the walls downstairs. The dogs would scramble and the wife would complain. The towers were missing something though. No live music sound. The soundstage was weak. The drivers seemed asleep. I thought I'd experiment with some home theater preamps like Anthem Statement D1 and the Parasound C2 (?).
Now the CP800. I was surprised how much preamp you can get for a few hundred dollars used. I didn't care for the Anthem. It isn;t designed for music. Too noisy. The Parasound was a surprise. Very nice and quiet. Not high end though. The Classe though---Oh Boy!! The towers on my Snells woke up! Super soundstage. The speakers disappeared. Fabulous. The 18 inch woofers died!! No life. Wimpy. The same has been true for all of the three preamps I mentioned.
Present setup- The CP800 is output; MAINS to the towers amp.. SUB and AUXILLARY ONE to the amp for the subs. NO Analogue bypass. The woofers do move but not like they should. I don't understand all the EQ functions. Classe says to have a qualified dealer set it up with proper equipment. I don't have a dealer. I bought it here on Audiogon. Any help is appreciated. Thank you. Joe