Can you ever have too much power?

As alluded to above, I agree with matching amp power to speaker needs. After going to Vandersteen 5 speakers that have built in 400 wpc amps to drive their built in sub-woofers, I went from a huge 300 wpc (McCormack DNA 2 Rev A) to a 100 wpc of equal quality (McCormack DNA-0.5 Rev Gold), and lost nothing in music quality/character.

In fact I now prefer the 100 wpc amp for its user friendliness, and lost nothing in sound quality. The DNA .5 Gold is considerably less expensive too;>) Cheers. Craig

Stne418, here you go!

Basically, it's a geometric progression. For POWER (watts) a 3dB increase requires a doubling of power, a 6 dB increase a quadrupling of power, a 9dB requires 8 times the power, 12 dB requires 16 times the power, etc. Voltage dB is the same doubling, except the measurements are expressed as 6 dB increases when voltage is doubled. Here are the formulae:

dBv (volts) = 20 x log E2/E1 (where E is voltage)

dBw (watts) = 30 x log P2/P1 (where P is watts)
by Fatparrot

Rogo - within reason you cannot have too much power. Amplifier-control of the speakers is one issue, headroom is another equally if not more important issue. My speakers are rated 100w/ch, but they consistently sound better with a 200w/ch amp, or more. Small amps, when overdriven, are what generally causes blown speakers. It is harder to damage a speaker by overdriving it with a big amp than with a small amp which is into clipping. If you occasionally like to crank it up then a larger amp is called for. If not then some of the issues raised above are indeed to be considered. I generally listen at only around 2w/ch, sometimes 20w/ch, sometimes more. At said 2w/ch level I have 100x that power level for an ideal 20dB of transient headroom.
Doubling or halving of power is a 3dB change, which seems like a lot but it isn't actually that much. Going from 1 to 2 watts = +3dB. 2 to 4 watts is +3dB. In the other direction, 100 to 50 watts is -3dB. 50 to 25 watts is -3dB.
for POWER:
1dB = 1.25x
3dB = 2x
6dB = 4x
10 dB = 10x
20dB = 100x

voltage (dBv) is measured differently however.

Bob bundus
Nicely articulated response.

Bob bundus. I agree with Jsteigert - That was a concise and ealsily understood response. And also with Nalu's closing analogy. A far better visual than mine. Thanks everyone.