new at this

I have B&W htm1 center,cdm-nt9 front, cdm-nt 7 rear. Adcom 7500 (5 by 150) amp and Adcom pre amp. Mids and highs are harsh from mid volume on up. Could this be due to cheap rca cables? ( I have Radio Shack's best!) Front and center speaker cables are big....the size of car battery cables. The wires inside look to be about 14 guage. I paid about 5.00 per ft.....not sure what brand. Rear speaker cable is Monster 14 guage. Front speaker cables are about 8 ft long....rears are about 25 ft. Music source is usually Comcast Cable digital music channels or 250.00 Denon CD player. So, is it cheap rca's, cheap speaker cables, all of the above, or none of the above? There are ton of cables with a 5 channel system and I do not want to spend a lot of $$$ and not hear the difference. If new rca/speaker cable is the answer, what would you recommend?
Also, I have seen power cables discussed here. Is that the power cable from the amp to the wall outlet? Am I to beleive that matters too?
I asked these questions at my local high end store and was told I need new cables. Another said I need a new amp, possibly Rotel, and went on to say that beyond Radio Shack sheilded rca cable I would not see much improvement. I am forever the sceptic when talking with commissioned salespeople! I would like to know what people who play with sound systems for the love of it would have to say. Your comments are greatly appreciated.
What's your room like?

If a store told you that you need new cables, they have to be right! Tell them to prove it, to give you some demos to take home and try. If they won't do that (they can get your credit card number for security) they're jerks that you may not be able to trust.
I have had rotel amps and have looked seriously at Adcom, and I don't know that there is much difference between the two within the line. Cables can make a big difference, but I would look at the source first. Cable merely transmit signal. Some do it better than others, but if you have harshness like you mention, it's more likely to be the Denon. Sorry!
Better cables might tame some of the harshness that is introduced by the cables, but better cables could sound even more harsh if the issue is the Denon. Borrow a CDP from a friend and see how much difference it makes. Less expensive gear is built around compromises, the ones you hear might be part of the design inadequecies of your gear, or the cables. It's difficult to point out the source of the problem without actually swapping things in and out.
do you have access to demo other amps/sources/cables? i would try to see what's causing the problem before investing any cash. home demo, buddies, local audio clubs could provide you an opportunity.

aloha keith
Did not know about the home demo option for cables. The room is big (24 by 28). Sounded just as bad in a room half that size. As far as the source is concerned, I hear the same level of harshness whether it is the cable box or cd player. Based on what you guys have said, I suspect it is the cables. For my modest system what should I pay for a decent pair of six foot rca cables? I suppose there is a point of diminishing return. Thanks for all of your help.
I had an Adcom preamp and Adcom amp (7500 also) combination before. I switched to a Sunfire preamp and Sunfire amp combination. I'm happier with the Sunfire vice the Adcom. The Adcom seemed to lack in overall strength/authority (amp) and my system sounded thin. The Sunfire is definately warmer and stronger sounding.

My speakers were and still are Klipsch Legends (horns) so they tend to be on the bright side. To get the mids and highs under control (at least for my system), NBS cables were the miracle answer. The mids were transformed and the highs were much more tolerable.

As others have noted, the source is important. I just switched from a modified Music Hall CD-25 to an EAD cdp. The sound again improved becoming smoother and much, much more analog sounding.

IMHO, NBS cables and the source would be a great start for you.

I think your main culprit is your Adomcom amp and CDP.

I dont think you Adcom 7500 is up to the task of driving any of your speakers properly. You are underpowered for sure.

Cabling is not the problem here.

Note: Be prepared to spend $ on amplification for your B&W's.

Good luck
Thanks Fife. I am starting to think a new amp would be a good idea. What would you think of Adcom GFA 7805 300 by 5? I am thinking about using both the 7500 and 7805 bi amp if the 7805 alone is not enough. If I do go the bi amp route, do I put the bigger amp on the bottom end?
try USEDCABLES.COM they will take notes of all your gear and give you what they think will work for you, and with a credit card will send you several options and you return the ones you dont decide to go with, great option for budget!!!!!!!!!!!!!
Problem solved! First and foremost, thanks to all who helped. A new amp was the answer. I went from 150 by 5 to 300 by 5. Both Adcom. I still have the same cheap IC cables and cheap Denon 2910. I have a new Denon 3910 on the way. I would not have bought it if I knew what a difference this amp would make. New cables are coming too. I cannot possibly imagine this system sounding any better than it does now. I am embarrassed to say that I think the harshness I was hearing was the amp clipping! Someone at told me about the clipping possibility and suggested I try more power before I try new cables. How's that for honesty? I am sure there are those who responded to my questions that thought about clipping. Probably assumed I would know clipping when I heard it. Thank you for that I said....I am new at this! Vman71 and Fife nailed it with their responses. Thanks, man! By the way, my closest neighbor is 1/4 mile away. He commented that he likes my new Tracy Chapman CD. What do you suppose he was trying to say?