I want to change from 2 channel to HT but what....


I have a very good Karan KAi180 integrated amp, a diy cd player and Merlin VSM-m speakers. I would like to sell the Karan and purchase a used or new HT receiver or separates. I want to spend around $2500.00 (the used price of my Karan). I am looking at, in this order, B&K 507, Sunfire receiver or separates like the Lexicon MC-1 with a good amp. I have also read some good info on Yamaha, Denon and a new Samsung digital receiver. I have also read that Sony has a digital amp in a receiver as well. The Samsung is out of my price. My plans for the near future is to buy a new Panasonic 50" plasma. I would like the hdmi switching, 7.1 and THX Ultra. I don't think the B&K 507 or the Sunfire has these. I am not realy keen on Sony, Yamaha, Denon, Onkyo or Samsung etc. receivers for the only reason that I would not buy one for a 2 channel set-up, but I am willing to consider everything. I do want at least 170wpc, THX Ultra, DTS, DD, 7.1 and a good video switch hopefully with HDMI. I do believe a good receiver can sound as good as separates. Mybe not in my $2500.00 price range. My Karan integrated was an upgrade from $7500 Melos separates.
stereo
Thank you all for your suggestions. I like the comment on the Arcam biamp ability and comment about why I need 7.1 not 5.1. I am leaning toward the Arcam. If I can run a 5.1 system and biamp my speakers with the other two extra chanels until more movies use 7.1 then I think the AVR300 is the amp for me. The reviews on the AVR300 are fantastic. Where did you purchase your AVR300 for $1600.00?
I moved from a 507 to an Anthem AVM20. It cost me 1,700. I paired it with two Citation 7.1 amps (cost of 1,800 for 8 channels of amazing 150 watt power), four channels each. Very satisfied with the move, a big step up in sound. The Anthem has a better upgrade path then most at resonable costs, sometimes FREE (i like that). Plans are in the works for HDMI swithing to be backwards compatible to the AVM20 - of course a chassis modification will me a cost involved. That is the only video switching I'd spend money on, so I'm content to wait. My tv monitor, like most, just has one DVI connection.

I will say the B&K is very user friendly and has THE best remote of them all. The sound certainly is fine but nothing compared to having seperate amplification. I did a work-a-round because I missed the B&K remote so much I purchased an MX-850 off e-bay... an even better remote then the B&K oem version. Highly recommended... I even have it controling $125.00 worth of Lutron Spacer System dimmers in my room now... its the best!

B&K will charge a lot for their upgrades. Anthem won't. The Anthem's processing control over virtually every aspect of the sound is amazing... tweak till you drop, if so inclined. And their customer service is terrific, although I enjoyed that with B&K as well.

At $1,800 +- for the AVM20, $800 +- for an MCA-5II (5 channel) your at 2,600. I know you want 7.1, but after making that move myself adding 2 speakers, I wouldn't do it again. Your room may dictate all those speakers and I thought mine needed it but it was a waste. Better off with 5 idealy matched speakers then 7 in my book. By the way... the Anthem will allow you to automatically switch to your rear speakers for SACD/DVDr for instance and back to a standard configuration for 7.1 movies! How's that for control?? So if really want another 2 channels, those amps are around 500 more.

Just my thoughts.
I moved from a 507 to an Anthem AVM20. It cost me 1,700. I paired it with two Citation 7.1 amps (cost of 1,800 for 8 channels of amazing 150 watt power), four channels each. Very satisfied with the move, a big step up in sound. The Anthem has a better upgrade path then most at resonable costs, sometimes FREE (i like that). Plans are in the works for HDMI swithing to be backwards compatible to the AVM20 - of course a chassis modification will me a cost involved. That is the only video switching I'd spend money on, so I'm content to wait. My tv monitor, like most, just has one DVI connection.

I will say the B&K is very user friendly and has THE best remote of them all. The sound certainly is fine but nothing compared to having seperate amplification. I did a work-a-round because I missed the B&K remote so much I purchased an MX-850 off e-bay... an even better remote then the B&K oem version. Highly recommended... I even have it controling $125.00 worth of Lutron Spacer System dimmers in my room now... its the best!

B&K will charge a lot for their upgrades. Anthem won't. The Anthem's processing control over virtually every aspect of the sound is amazing... tweak till you drop, if so inclined. And their customer service is terrific, although I enjoyed that with B&K as well.

At $1,800 +- for the AVM20, $800 +- for an MCA-5II (5 channel) your at 2,600. I know you want 7.1, but after making that move myself adding 2 speakers, I wouldn't do it again. Your room may dictate all those speakers and I thought mine needed it but it was a waste. Better off with 5 idealy matched speakers then 7 in my book. By the way... the Anthem will allow you to automatically switch to your rear speakers for SACD/DVDr for instance and back to a standard configuration for 7.1 movies! How's that for control?? So if really want another 2 channels, those amps are around 500 more.

Just my thoughts.
I recommended the Anthem because it a huge bang for the buck, will compete with gear costing twice as much -- and because I don't believe you will be happy with a home theater receiver -- I believe you will quickly wish you'd purchasd separates. So, factor in the cost of buying a receiver, shipping it, realizing you're not satisfied, selling it, and buying separates. Now, think of the time and money you'll save going directly to separates -- and you can still buy an Anthem AVM20 and a 5 channel amp [used] while staying under your budget of 3,000. Also, as Sailfish mentioned, they offer upgrades from time to time, which will help you stay current.
7.1 isn't going to happen. It's bad enough getting all the extra channels of amplification and finding, locating extra speakers 5.1 much less for the very minor improvement in surround performance in 7.1.
Likewise, bi-amping is a minor improvement for the $ involved. There's better places to put your $.