[Trevor]

On 20/04/2019 7:41 am, Mike Rivers wrote:
On 4/19/2019 3:41 PM, James Price wrote:
When viewing general specifications for guitar speakers, the frequency
response curve often displays a larger frequency range than what's
listed under the "Frequency Range". If the listed frequency range is
70-5000Hz, yet the frequency response curve shows activity below 70
Hz, is the speaker audibly reproducing the extended lower range in the
plot? If so, what is the listed "Frequency Range" actually denoting?

The frequency response plots, as well as the operating characteristics,
come from the marketing department, not the engineering department.
Sure, the speaker will reproduce something below 70 Hz, but as a guitar
player, you probably don't need it. What they want you to believe is
that it will do a good job as a guitar amplifier speaker, which,
hopefully, is why you're buying it.

The raw stated or plotted frequency response of a loudspeaker is more
theoretical than practical, since in the real world, it's a function of
the amplifier, the enclosure, and even the wiring between the amplifier
and speaker voice coil.

You forgot the main thing. The response figure quoted is a function of
what you specify as the limits for acoustic output. Most speakers will
reproduce down to 20 Hz in no enclosure at all. Of course the output
will be so low that you cant hear it or feel it! You may be able to
measure it though. Now that marketing dept can select any dB limit they
like for the frequency range, so when they do actually show a plot (not
very often unfortunately) you have far more information to work with.
You still don't know how accurate the plot is of course! :-(
And it will certainly be different in your enclosure and room in any case.