[LAU] speaker frequency response measurement and display

[Chris Caudle]

On Fri, June 24, 2016 10:06 am, james wrote:
> Or you can put the speaker on (or in) the ground pointing up, and
> suspend the microphone.

As Will pointed out, that will not be the same as true free field response
because any sound which would have radiated to the rear (typically just
low frequencies with a box style speaker) will be reflected back to the
front.
Possibly you could compensate for it, but measurements of output vs polar
angle become difficult (e.g. to measure output at -180 degrees you would
have to put the speaker face down on the ground).

To the original poster: don't forget to spin the speaker around and
measure at various angles off axis.  The frequency response of the sound
which is emitted off the main listening axis and gets reflected from
nearby walls has a very big influence on the perceived frequency balance
of a speaker.

-- 
Chris Caudle