When it comes to mids and highs, efficiency (sensitivity) is a fairly
good indicator of output differences at the same power level. When it
comes to subwoofer performance, the driver's sensitivity is irrelevant
unless you are also specifying a box volume.
An efficient sub requires a larger box to achieve equivalent extension
to a less efficient sub. In a small box, the less efficient sub will
actually be LOUDER at low frequencies at the SAME POWER as the more
efficient sub.
Linear excursion is a very good indicator of ultimate output capability
(given sufficient power to drive the speaker to that point.) To make
sound you must move air; therefore, the more air you move, the more
sound you make. When comparing two speakers of equal surface area, the
one with greater excursion capability will play louder given sufficient
power.
good indicator of output differences at the same power level. When it
comes to subwoofer performance, the driver's sensitivity is irrelevant
unless you are also specifying a box volume.
An efficient sub requires a larger box to achieve equivalent extension
to a less efficient sub. In a small box, the less efficient sub will
actually be LOUDER at low frequencies at the SAME POWER as the more
efficient sub.
Linear excursion is a very good indicator of ultimate output capability
(given sufficient power to drive the speaker to that point.) To make
sound you must move air; therefore, the more air you move, the more
sound you make. When comparing two speakers of equal surface area, the
one with greater excursion capability will play louder given sufficient
power.
My comment here is the same as it was to your identical post on another forum:
Driver sensitivity per se has no influence on cabinet volume [as in size] for a given alignment. Driver sensitivity is a result of its electrical & mechanical properties only. Assuming you're targeting a specific alignment, then this, especially for box speakers, is dominated by Fs, Vas and [effective] Qt', i.e. Qts + any series resistance in the circuit. Hoffman's iron law; pick any two, but the laws of physics prevent you having all three:
-High sensitivity
-Small size
-Low bass
As far as boxes go, an effective Qt of around 0.312 should provide the greatest extension in the smallest box for a given Fs, Vas. Note that it's possible to have a driver with, for e.g., moderate - low sensitivity and a relatively high Fs, so it will not necessarily go any lower than an equivalently sized high sensitivity driver.
Linear travel (Xmax) can be a reasonable indication of outright dynamic range -however, if you're going to make comparisons, in addition to driver Sd you have to factor in the nominal sensitivity of the system if you're going to establish which is going to go louder in outright terms. Don't forget also that there is no standard definition for Xmax -I did a count of different methods a few years back, and gave up at seven. Driver manufacturers do not always state which they used, although in some cases it's possible to work out what they've done, and they all give somewhat different results if applied to the same driver.
Driver sensitivity per se has no influence on cabinet volume [as in size] for a given alignment. Driver sensitivity is a result of its electrical & mechanical properties only. Assuming you're targeting a specific alignment, then this, especially for box speakers, is dominated by Fs, Vas and [effective] Qt', i.e. Qts + any series resistance in the circuit. Hoffman's iron law; pick any two, but the laws of physics prevent you having all three:
-High sensitivity
-Small size
-Low bass
As far as boxes go, an effective Qt of around 0.312 should provide the greatest extension in the smallest box for a given Fs, Vas. Note that it's possible to have a driver with, for e.g., moderate - low sensitivity and a relatively high Fs, so it will not necessarily go any lower than an equivalently sized high sensitivity driver.
Linear travel (Xmax) can be a reasonable indication of outright dynamic range -however, if you're going to make comparisons, in addition to driver Sd you have to factor in the nominal sensitivity of the system if you're going to establish which is going to go louder in outright terms. Don't forget also that there is no standard definition for Xmax -I did a count of different methods a few years back, and gave up at seven. Driver manufacturers do not always state which they used, although in some cases it's possible to work out what they've done, and they all give somewhat different results if applied to the same driver.
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A totally non-technical response might be - sensitivity is only one of several of the measurable parameters that affect speaker performance, but I think you need to define the real world conditions / compromises - and there are almost always some - under which any particular system will be expected to function before designing with any methodology beyond "gee, think this might work?"
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