measuring spl

[valhallax]

is there any general rules for measuring spl? pink noise at 10 ft or...

[bfish]

For comparison of Altec drivers to published data, using the same methods and standards they did will yield the best results. TL 203 and TL 220 give the "how to" details, including the formula for distance conversion.

Duplicating this method with software systems has one shortfall, the ability to band-limit the pink noise to a specified range, rather than a broadband sweep. In some cases, it won't matter much, in others it will.

[donaldpatten]

valhallax

Radio Shack has a SPL meter for a reasonable price.
One model had an output connection.

Don

[bfish]

SPL alone is merely a measure of any sound at any distance.

"Even in the parking lot, the Madman's concert reached 126dB".

Sensitivity comparisons are done at a standard reference distance, like 1 meter or 4 feet, with a specified power input level of a specified signal. For example;

"Sensitivity is based on a band-limited swept 500 Hz to 2.5 kHz sine wave at an input level of 2.83V, measured at 1 meter on axis".

The actual measurement may be done at a greater distance, and recalculated to relate to a standard reference.

Specifying all the variables allows accurate comparison. "My car used a $35 of gas coming up here" doesn't really tell you much. "My car gets 32mpg" does.

<font color="#FFFFFF" size="1">[ January 28, 2008 03:06 PM: Message edited by: bfish ]</font>