I had a few questions regarding how to calculate the amount of power you'll need to drive a set of speakers.

So, let's say that you get speakers that are rated at 91dB at 1Watt of power, 1 meter away from the speaker.

From what I've read, you have to double the power to get 3 more dB out of that speaker.

91db @ 1 watt

94db @ 2 watts

97db @ 4 watts

100db @ 8 watts

103db @ 16 watts

106db @ 32 watts

109db @ 64 watts

then for a true 100 watt amp, at max volume, you'll be getting around 110db or 111 db at 1 meter, right?

Well, that's only 1 meter away, and I have no idea if full power means "max power output before the amp starts distorting."

So:

:scratchchin:

Thanks for helping a new guy out...

So, let's say that you get speakers that are rated at 91dB at 1Watt of power, 1 meter away from the speaker.

From what I've read, you have to double the power to get 3 more dB out of that speaker.

91db @ 1 watt

94db @ 2 watts

97db @ 4 watts

100db @ 8 watts

103db @ 16 watts

106db @ 32 watts

109db @ 64 watts

then for a true 100 watt amp, at max volume, you'll be getting around 110db or 111 db at 1 meter, right?

Well, that's only 1 meter away, and I have no idea if full power means "max power output before the amp starts distorting."

So:

- Typically, do respected amps start distorting at a certain % of the max output? (I'm talking about denon, harmon kardon, emotiva, krell, etc: not off-branded crap you'd find in a white van like Sorny or Fillips, Panasonique)
- How much in terms of loudness do these figures get reduced as you add distance from the speakers. Say at 2 meters through 4 meters.
- Does the fact that there are 2 front speakers add another 3db to the figures above, because you're double the power of just 1 channel?
- (How) Does speaker placement in regards to walls/other objects affect the loudness level like it does for subwoofer placement. (for the sake of the topic, I'm not really interested in echoing, just loudness.)
- Is max input power on a speaker specification a easy way of saying "Max volume:" In which case, a 200 max Watt speaker shouldn't be pushed past around 112-113 dBs?

:scratchchin:

Thanks for helping a new guy out...

## Comment