Speaker impedance

[bumpy]

Everything else being equal, should a 4, 8 and 16ohm version of the same driver sound the same. Thinking aloud, I would guess the 16 ohm version would have a heavier voice coil and hence be a bit 'slower'

[Macca]

I'd guess the nominal impedance of a drive unit would have very little effect on how it actually sounds aside from that the lower the impedance the louder it will be for the same input. But even that is amp dependant, some amps actually reduce their output as impedance drops.

[Stratmangler]

I don't know why folk are resistant (pun intended) to using google, but they are.
This article is very good https://geoffthegreygeek.com/understanding-speaker-impedance/

[Light Dependant Resistor]

I'd guess the nominal impedance of a drive unit would have very little effect on how it actually sounds aside from that the lower the impedance the louder it will be for the same input. But even that is amp dependant, some amps actually reduce their output as impedance drops.

Quite correct Martin. Valve amps reduce output presented with low impedance speaker loads, some valve amps have transformer taps to try and assist this,
but at the other side of the coin provide higher output with higher impedance speaker loads

Solid state does the opposite reducing output with high impedance speaker loads, and increasing with lower impedance speaker loads
The differences are explained here: http://education.lenardaudio.com/en/14_valve_amps_7.html

As regards how each sounds, lets assume we have a amplifier halfway somehow between valve and solid state the best implementation would tailor the
speaker impedance to try and avoid big variations, as this then can reduce or increase output at certain frequencies when connected to our ideal a amplifier.
That said the ESL57 that is generally regarded as having a flat frequency response - in its useful range. But its impedance curve is atypical of electrostatics being all over the place.
It needs certain choices of components at the amplifier to amend its weird impedance curve. The 303 amp being fitted with these components. http://www.audiomisc.co.uk/57and303/interact.html

[Macca]

There are solid state amps that reduce output into lower resistance loads though, although I agree it is not typical. Usually because their power supplies are cheap crap. From memory I think some Audio Analogue amps exhibit that behaviour.

[bumpy]

I don't know why folk are resistant (pun intended) to using google, but they are.
This article is very good https://geoffthegreygeek.com/understanding-speaker-impedance/

Because articles like that look at the maths and amp capabilities. Not once does it mention SQ which is why I turn to the good folks on here.

[Stratmangler]

Because articles like that look at the maths and amp capabilities. Not once does it mention SQ which is why I turn to the good folks on here.

You didn't mention sound quality in your first post.

[bumpy]

You didn't mention sound quality in your first post.

"should a 4, 8 and 16ohm version of the same driver sound the same" Perhaps this phrase needed explaining :)

[struth]

no real reason for there to be much difference sonically, if driven well enough. used to use a set of 3 ohm and a set of 15 ohm... lol. not same speakers tho so, yes they were different. if you got same speakers with different resistances from same maker they shouldnt sound much different bar the amount of watts needed to move them

[Barry]

Everything else being equal, should a 4, 8 and 16ohm version of the same driver sound the same. Thinking aloud, I would guess the 16 ohm version would have a heavier voice coil and hence be a bit 'slower'

The mass of the voice coil is largely negligable compared with the mass of the cone. So I would have thought it would make little difference to the inertia of the driver, and hence 'speed'.

Valve amplifiers use an output transformer to match the speaker impedance (a few Ohms) to that of the output valve(s) (several kilOhms). Most have speaker impedance taps on the output transformer to make the output independant of speaker load (which also alters the feedback ratio to preserve frequency response).

Solid state amplifiers don't use an output transformer (though a very few do), so the quoted output is quoted for a specific speaker load impedance.

[bumpy]

Thanks guys for confirming that speaker impedance per se does not change SQ and that its all about amplifier to driver matching.