Yeh well I'd spend my money on Denon over HK any day.
I believe and stand to be corrected on this although I am 95% sure I am right, Dynamic headroom would be if you are listening to your sound system at say 50% and there is a explosion the volume inceases drastically eveen though you are not turning up the dial it still pushes the wattage out. The head room part is that you have enough wattage there that the amp doess not distort when it it produces these levels.
I can see how if you turn up the volume until you get distortion but I do not think it has the same effect as a sudden burst of energy.
I beleive that a 70 wpc Denon will not clip as easily as say a 70wpc kenwood even though the wattage is the same I will bet the Kenwood will clip way beore the Denon. But hen the Denon is a high current quality and the Kenwood is well Kenwood.
Then again a 70wpc Carver Cinema Grand will ick volumes galore over the Denon but at $3000 more.
I know the Denon you have is alot better than most amps your gonna buy in the 70 - 120 watt area unless then of course you can buy a Sunfire
PS stay with the Denon over the HK in terms of attage the Denon900 I had was 70wpc and the HK 510 I have now the Denon is was louder at the same 50% level
