HELP Why no bass? Why bright?

Sydney- My experiences, as Phild stated, have proved to me the necessity to allow components to "break-in". With all due respect to Perk, all of the vendor spec sheets that I've seen indicate that component drift or variation occurs more profoundly during the initial and then again near the end-of-life operation periods. Most of this is due to thermal effects, both steadystate and cyclic. Last I looked, electronic components were composed of quite a few resistors and capacitors, and tubes and/or transistors. I agree that if a component is "bad", that time will rarely repair it for you. However, the sound attributed to components does and will change over time, and predominately during the initial use period.
As for your system, was the integrated the only piece that you changed(are the ICs and/or speaker cable new?)? After the amp has been used for at least a week, you can then determine if you need to consider speaker placement tweaking (toe-in/tilt), some room treatment, or possibly try other wires to help shift the tonal balance to more of your liking. Take your time, and enjoy.

Thanks Perkadin. Which speakers do you recommend to mate with Arcam? I listen to rock, but detest brightness. I am in the market and have the B&W's on loan.

Thanks jctubes. Any particularly warm interconnects you've got experience with? How about speaker cable? I guess I just expected more bass from the CDM7 NT. I actually auditioned the Dynaudio Audience 72 along with the MIT Terminator 4 speaker cable and was very pleased with the bass response. I was told that the CDM7 had even better bass, though I haven't tried them with the MIT cable, so I don't know if the bass extension was a result of the cable or the speaker.

Gotta blame the B&W tweeters. Balanced quite hot.

...or face the other possible that can happen: you can simply adopt to that brightness or tightness and say OK you were guys right, after 600 hours the system had opened and is no more bright!