Looking to upgrade


Hello, I'm looking to upgrade my home theater system and was trying to figure out where to start. I was thinking starting with an old Lexicon DC processor and 5 channel amp. I don't want to spend an arm and a leg, but want to improve the overall sound over my setup which includes:

Original KEF 105's mains
KEF C100 center channel
NHT VT-3 surrounds
SVS PB12-ISD subwoofer
Marantz SR-18 receiver
PS3 for Blueray/DVD

Any suggestions would be appreciated.
teslaroadsters
Thanks for the suggestions. Elevick, can you recommend an inexpensive line conditioner? I think I'm going to pick up a Lexicon DC and also take a look at B&K amp. Regarding price range, around $2000.00 to upgrade. Is it best to spend the money on processor and amp, or should I be looking to change speakers. BTW, 100% of my system is dedicated to TV/Movie surround sound. I never listen to 2 channel stereo.
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I agree with Teslaroadsters, changing your speakers will make the biggest difference. Try to match them all, or at least the same series (where usually the only difference is the size of the woofers).
Bob, if I upgrade to Evolution 5 or 6 do my NHT VT-3 still work okay as surrounds or do those need to be upgraded as well? Thanks
The KEF 105 are great speakers. They are much more musical than NHT. I used to own a pair for a short period in 1980. Don't change them if they are in good shape. But I would suggest you find someone to rebuild the crossovers. After so many years, the capacitors must have been deteriorated and that will change the crossover point and degrade performance. Without a properly working crossover, you have no idea how good they can be.