Help- why do my Definitive Tech BP7001's sound Bad

About a year ago I purchased a brand new pair of Definitive Technology BP7001SC speakers. The problem is I am not satisfied with the sound I am getting from them. They sound good (but not mind blowing) on some recordings such as Diana Krall’s “Girl in the Other Room” and James Taylor’s “Hourglass”. They even sound good on some earlier remastered recordings like The Band’s boxed set. But for many recordings (more “rock” oriented with lots of guitars and layers of sound), Cd’s and LP’s, they sound harsh, fatiguing, and the mid range is flat and muddy. My other complaint is on many recordings the vocals sound “buried” in the mix- not as prominent as they should be. I am running them off a Denon 3805 (120 Watt per channel) receiver. This was one of the top Denon models a couple years ago (replaced by 3806 I think). Receiver was highly rated and seems to work fine. I listen to mainly music and do not yet have surround sound, so I am talking strait 2 channel stereo here. I know a lot of audiophiles say Def Techs are not great for music only but I have also read many glowing reviews of the 7001’s for music applications. I am thinking my room may be part or all of the issue. The room is full of hard surfaces- pergo floor with area rugs, sheetrock walls, not that much furniture, no drapes, etc. The dimensions are 27 x 18 feet with a 14’ high cathedral ceiling. The system is situated on one end of the 27’ wall (1 speaker near corner of room), speakers about 9 feet apart and angled slightly in. The main listening area is about 15-16 feet away (alone the opposite wall) and centered on the speakers. Actually my biggest praise for the speakers is how relatively GOOD they sound in all parts of the room. But they don’t sound that GREAT even in the prime listening spot. I have tried facing the subwoofers out vs. in and this does not seem to matter. I have also tried moving the speakers closer and further from the back wall and changing the angle, and this has not cured anything either. Right now they are about 14-16” from back wall. I currently have the speakers connected with 14 gauge speaker wire thru the “mid range/ standard” hookup method. I tired the subwoofer LFE hookup and this makes no audible diff for music. Overall, they just don’t have the WOW factor I was expecting for the price. I actually never heard them before buying. I did audition the smaller 7002 in the store and liked that so figured the 7001 would be even better. And for half price I could not pass them up.

So what do you guys think:
Are the speakers just crappy for music? (how can a 3500.00 speaker by crappy?)
Would bi-amping help the sound to any great degree?
Is the shape of my room the problem, particularly with the bi-polar config?

Any thoughts would be greatly appreciated!!
I can bet on this one. I would say hook up your speaker's to an older Classe DR-9amp with some muscle and you will have a new speaker. You can run the Denon as a pre or buy an older tube unit or stay with Classe and get yourself a DR-5 preamp. I will say a better combo for the money can't be found.
A tube source helped my older BP 7000s come to life. I had the same complaint when the BP7000 were new (1985) hooked up to the then top of the line Denon AVR 3600 and the next to the top of the line Sony DVD player. My CD's sounded flat and metallic with no real warmth I fondly remembered vinyl lps with. After years of equipment upgrades including first a DAC upgrade w/upsampler, later an ARCAM CD player nothing noticably improved. Over the years living room HT system evolved into a Sunfire Audio processor with an Odyssey Stratos (3 Channel model)and a top line Denon DVD player which gave GREAT movies sound but the music CD's never sounded as involving as my separate stereo only system. It was by chance I received a used Marantz 5 CD player as a gift and I hooked it up as a "convenience" piece for house parties and hooked connected it a Cal Audio Sigma I DAC (which was a spare as I upgraded to the II for my stereo only system). I'm absolutely amazed at this system's sound! I never expected the BP7000s to sound SO GOOD, about 95% of my stereo only (An all tubes, monoblock amps, VPI Scoutmaster turntable system). I enjoy the huge deep sound stage of CDs with warmth and bottom I had given up of ever expecting several years ago when I first got the BP 7000s. Accoustic instruments, jazz, and vocalists, sound warm and involving. Gold CDs and MFSL discs sparkle even more revealing greater musical detail and ambience. The Gold Discs of the Allman Brothers Live at the Fillmore East and Cannon Adderley's "Know What I Mean" sound wonderful. Given they are rear firing speakers, they produce a bigger enveloping sound than my stereo only system. In short, the Def Tech towers are capable of exceptional musical reproduction with their own dipole touch but it took me years of finding the right electronics and it was purely by chance I hit upon a winning combo. Try a tube source like a tube DAC for your digital or an even a tube FM turner and see if the sound improves to your liking. Though my Def Techs are over 15 years old, I have no interest in replacing them as my living room HT/second stereo speakers. Good luck.
A decent DEQ will help with your room. They can be quite inexpensive and drastically improve sound.
A tube source helped my older BP 7000s come to life. I had the same complaint when the BP7000 were new (1985) hooked up to the then top of the line Denon AVR 3600 and the next to the top of the line Sony DVD player Jwong (Answers)

Jwong, the Def Tech BP 7000's were not released until 2003.
I don't have any experience with the Def Tech BP7001s, but do have some experience with dipolar and bipolar speakers that might be applicable.

Briefly, the ear does not like early reflections but it does like late-arriving reflections. The ballpark transition zone is around 10 milliseconds. Sound travels a little over one foot per millisecond.

Cjmbl, you might try placing your Def Techs 5 or 6 feet out in front of the wall behind them, such that the reverberant energy from the rear-firing drivers begins to arrive after about 10 milliseconds of time delay (round trip distance of 10-12 feet). Even if room aesthetics prevent your leaving the speakers in this location, try it as an experiment to see if the problems you hear arise from the early onset of a lot of reverberant energy, or from something else.

A good dipole or bipole can sound rich and lifelike when set up appropriately, but with a significantly sub-optimal setup they will not sound as good as an equivalent monopole.