Noes - First Mesurements

I still don't have crossover parts, but that's no reason why I can't do some interesting measurements.

Fee Air ScanSpeak Impedance

 Fresh out of the box in free air the speaker resonance is around 49 Hz at around 31 Ohms.  I believe I read somewhere that ScanSpeak specifies the Fs after break in, so I should probably measure this again in a week or so.

 

To begin with, a full-range frequency response chart for the woofer.  Incredibly clean at the upper end of the spectrum, even when averaged at 1/24th octaves.  This is with the speaker on a chair and microphone 3ft away on the woofer axis.

Next up is the impedance measurement in the cabinet.  The woofers have only been playing for about 4 days with low to medium jaz 24 hours a day.  I'm going to have to go back to Lee to ask for help interpreting both of these.  From the first chart I worry the box is a little large.  Below is the chart I really don't know well, the speaker + cabinet impedance. 

I can see the port resonance at 24 Hz, and a second resonance at 69 Hz.  The valley's nadir is around 35 Hz, somewhat lower than the driver's Fs when first purchased.  ScanSpeak specifies the Fs at 33 Hz after break in, in which case the tuning would be spot on.

I have a week before I can assemble the crossover, so I have time to plan ahead.  With Thanksgiving coming up parts will be slow in arriving.

Of course, there will be more later.