Decware Project-X FRX Owner's Manual page 13

O W N E R S M A N U A L
It then became obvious that there was a 1ms delay in the measurement software causing it to read the
response just before the stimulus signal. Even though I thought it was awfully good response, I also
knew the measurement system was working because of the waterfall plots and a myriad of other
reasons. And what I was hearing was unusually smooth which helped to confirm it. So I guess the joke
was on me.
But keeping it all in perspective, a speaker has many frequency responses. The response depends on
where the microphone is placed. The response it measures at 1 foot or 1 meter is certain to be what you
DON'T hear unless you listen at that distance. At an average of 12 feet away from the speakers it has
taken about 13.2 milliseconds for the sound to travel from the speaker to your ears. As it travels through
the room it is modified by the room and the natural dispersion patterns of the speaker. If you look below,
13.2 milliseconds is just where the color starts to turn yellow, which short of a little peak at 10K is fairly
smooth. This is what you actually hear.
So adjusting the software for the 1ms delay I was able to publish what I'm sure is a far more accurate
response and it is very similar to the independent lab's IEC baffle measurements. Sorry for any trouble
this has caused, it wasn't intentional and I was able to delay production until this got resolved.
Steve Deckert
Decware / High Fidelity Engineering Co. East Peoria IL USA www.decware.com