Help: why the speaker sound is so low?

I recently set up my first system:

NAD C521i CD player,
Arcam A65 plus integrated amplifier (4-16 ohm, 40 wpc),
Tannoy Saturn S8LR speakers (10-120 Watts),
Radio Shack interconnect cable and speaker wire (16 gauge).

The problem is the speakers sound extremely low and thin, which I believe is anything but normal. I have tried using a pair of old AWAI speakers, and they sounds normal. When I connected the Tannoys to a AWAI receiver to hear TV, they again sounds very low and thin. I also tried 12-gauge speaker wire from RadioShack, it does not change anything. All wire connections have been double checked or triple checked. There should be no problem about the wiring.

I am wondering if this could be a problem of the speakers? Although the sound is low, the two speakers sound symmetrically. Are there any settings on the speaker or amplifier I missed?

Your input is highly appriciated.

Yi