Going from 100 wpc to 250 wpc would be an appr. increase in power by 3.75 db's. In theory, this may not seem like much. In reality with power hungry speakers, it can make a WORLD of a difference.
When i changed amps in one system using "power hungry speakers", i went up 1 db and it made a very noticeable difference. While most would say that 900 wpc would be enough for ANY speaker, i was still able to drive the amps into compression. Replacing the biamped pair with one amp rated for 1200 wpc made a world of difference in terms of "never running out of steam" and the increase in "ease of reproduction" and "liquidity".
Keep in mind that a low sensitivity reading at 1 watt does not necessarily make for a "power hungry speaker". Even though some speakers are not real efficient at low levels, they can play quite loudly with just a bit more power into them. Other speakers may take a boatload of wattage to play at that same level. My findings and experience are that the more complex the crossover is, the more power it will take to "rock the house". Much of the power that the amp is generating is "eaten up" by heat in notch filters, impedance compensation networks, etc...
As such, the Dynaudio speakers use very complex crossovers with a lot of parts in them. Much like the speakers i'm using in my HT system, they will "drink an amp dry" if you give them the chance to. Sean
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