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General speaker questions for audio and home theater.

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RE: You might want to review that...

Posted by Presto on May 10, 2017 at 10:12:03:
"Sensitivity is, and always has been, expressed in 1W/1m."
Okay, that might well be incorrect. Here, let's try this:
"Sensitivity, in my travels through domestic speaker specifications, has almost always been expressed in 1W/1m"
They will also say "1m SPL@2.83V". It's rare to see them cite 4V for 16 ohm drivers or 2V for 4 ohm drivers even though if they give 1W/1m as those are exactly the applied voltages. I've seen a lot of specs in pro-sound circles for four ohm driver which are at 2.83V / 1m. 2.83V vs. 1W can't be the same if you say "The 8 ohm version is 3db less sensitive than the 4 ohm version". If you use voltage as the reference, there is a 3db difference. If you use power (1W) as a reference they will have the same sensitivity, if all other design details besides coil impedance are observed.
This is why the *word* sensitivity (at 1m) can't mean 2.83V *and* 1W at the same time unless it's an 8ohm nominal driver or system.
This is why I thought they reserved "sensitivity" for 1W/1m and perhaps threw people off calling 2.83V/1m/8 ohms sensitivity as well.
I wonder if life would be easier if we said "1m power sensitivity in 1W/1m" and "1m voltage sensitivity in 2.83V/1m"

EV has SPL at 10 feet with, what was it, four volts applied?
From the EVM12S 12" mid-woofer specification sheet:
(EIA Standard SE-103 Section SE3).

The thing is, it's easy to get 1W/1m from the 10 foot measurement - just increase the SPL per the inverse square law for the SPL at 1m instead of 10 feet. (It's already at 1W).
If the person seeing the spec knows what it is and can compare apples to apples with other drivers/systems he's okay. For everyone else, it's not surprising there is confusing surrounding the terms and their application.
Cheers,
Presto