Sensitivity/Impedance

As far as I'm aware the MOre sensitive a speaker is, the louder it will be at a given input.

And that the lower a speakers impedence, the louder it will at a given input too?

Lower impedances mean the speaker requires MOre current, which may be too much for some amp's???

But what are the other possible pros and cons for both High and Low Impedance, and High and Low sensitivity?

What decides a speakers Impedance and Sensitivity values? Is it down to the different driver designs? The overall speaker design? Or is it tuned by the designer specificaly to get it sounding best? i.e is it pretty variable (and how?), independant of driver and cabinet?

Hope this makes sense and thanks

MO

 

The efficiency of a speaker is really

power in <> sound out

since power is volts x current, this is the actual
numbers. It is easier to compare speakers if we
use 2 measurements seperately

Voltage sensitivity
Impedance

Because our hifi amp is not a power amp. The label
is really 'high power voltage amp' because the audio is
volts coming out the amp. The current flow is a result of
what you hang on the terminals. To make all speakers
comparable we agree to measure the volume at 2.83V because
that would generate 1 watt of heat in an 8 ohm resistor

(2.83)²/8

The lower the impedance, the more power the amp gives in
order to output 2.83V [because it requires more current thru
the spkr, so the electrical watts are greater]

"What decides a speakers Impedance and Sensitivity values? Is it down to the different driver designs?"

Drivers and crossovers. Current is a necessary evil in speakers.

Impedance is a terms worth of higher study as it is actually 3 parameters combined together by fancy maths - best avoided unless necessary...

 

Very true. Welcome to the world of jw ("jay-omega")

(iw to mathematicians of course, but any engineer dealing with impedances knows I to be current...)

 

fancy maths couple of square roots ,a few plus and minuses and your there:MILD:
working out power factor on a 3 phase unbalenced load now thats fancy maths

 

U sparkies and your 50Hz...

Les, you would have liked the steelworks where I used to work

Arc melting 150 tonnes scrap in a big brick lined pot.
3 x 30ft carbon rods lowered through the lid - up to 80 Mw
from a v. v. big transformer via oil cooled wires a coupla feet
thick..And a CCTV camera in the switchgear room, to watch for
fires I guess, and to make ABSOLUTELY sure the switches were
open before anyone went close..Some crazies used to have to
clean the rim of the 'pot' every few hours [just the odd engine
block or train wheel wedged in the wrong place] so the lid fits
properly...