using the SPL calculator at http://www.myhometheater.homestead.com/splcalculator.html

as well as an SPL meter.

The calculator shows that the my amp and speakers will go to 103.5db at my 11 foot listening position. Well, my SPL meter shows I'm listening to about 94db at at pinfull levels.

My question is this... Given the results from the SPL calculator website, does this mean as long as I stay below listening levels of 103.5db I cannot clip the amp and speakers? Roughly speaking of course, I do realize all these are estimates and don't take everything into account.

 peak vs RMS - gymwear5@hotmail.com 07:47:39 05/11/07 (2)
 Thanks for the input....BUT........ - Steven 08:29:26 05/11/07 (1)
 Re: Thanks for the input....BUT........ - David Aiken 13:21:14 05/11/07 (0)

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 peak vs RMS - gymwear5@hotmail.com 07:47:39 05/11/07 (2)
 Thanks for the input....BUT........ - Steven 08:29:26 05/11/07 (1)
 Re: Thanks for the input....BUT........ - David Aiken 13:21:14 05/11/07 (0)

Here's how I figure it out. Start with The power amp and calculate its output level in dBW. Your 85W RMS Amplifier can probably go to 125Watts Peak for short periods... 1.7dB dynamic capability, but lets use 100 Watts as a nice round number - 100Watts = 20dBWatt.

So now since your speaker sensitivity is 90dB for one Watt (usually at 1 meter) two Speakers are 93dB - perhaps a bit higher say 4.5 dB because of the correlation between the loudspeakers signals. Depending on your room acoustics the level will drop about 3dB for doubling of distance. At 11ft that drops the output down to 90dB for 1 watt into TWO speakers again.

Using PEAK values you get 90dB for 1 Watt, 100 dB for 10 Watts, and 110dB for 100 Peak Watts - add 4.5 dB for the second speaker and their 103.5 goes up to 108dB - not to far off. Your Sound meter is likely +/- 3 or 4dB in accuracy.

Looks like your are doing just fine

Given, the numbers, you don't think I clipped, do you? Because as I say it was unenjoyably loud, although I heard no ditrotrion but do you think I clipped a little to the point where I didn't hear it yet?

Thanks again,
Steve

So, you find average levels of 88 dB "very, very loud", do you? You're not alone. My peak levels rarely exceed 85 dB using a RS meter, with average levels around 10 dB lower than that. Average levels of 88 dB are quite loud—I won't say "very" because someone is sure to disagree with the use of that word, but we are talking loud, especially if you're in a small to medium sized room. Peak levels will be around 10 dB or so louder and that's getting very loud by any definition.

I doubt you clipped and if you're not hearing distortion and you don't like it that loud, then your amp has no problems with your speakers and room at the volumes you like.

Relax. Enjoy. Put the volume control back where you like it and spin some music.

David Aiken