After fixing some seemingly insurmountable problems with my soundcard and computer, I was finally able to get some decent measurements of an 802-8g on a 511b horn.

I don?t remember which details I?ve already posted, so once again?

The 802 was re-magnetized at GPA, and received a new 34647 diaphragm. The bug screen was removed, too. The 511 horn, in addition to being finless, is damped with self-adhesive roof flashing.

I made the latest measurements using both Holm and REW. With REW, 1/24 smoothing was about as high in detail as I could tolerate on the crowded plots?.so all of the REW and Holm plots that are posted here have 1/24 smoothing. I don?t have an SPL meter, so the SPL is only relative within a particular plot. The measurement distance was four feet.

I was also curious about seeing the 802 / 511 combo being run through a crossover. For that I used a Zilchlab designed model 19 network, and installed an 8 ohm dummy load at the crossover?s LF output. Before making the measurements, I used REW?s pink-noise generator and RTA screen to adjust the two Lpads for the flattest response. The Lpad closest to the driver was set at maximum, and the other Lpad, which controls the FR slope, was set at minimum. I noticed that the tradeoff here is with efficiency? in pursuing a flat FR, the output went down..

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Plot showing a corrected trace (top) and the earlier contaminated traces (below) --
alteccomparisonwcontamith

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Plots created in both Holm and REW in order to cross-check the measurement systems --
80202040holmth
80202040rewth

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Plot of the 802/511, 0 to 90 deg --
80290th

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A less crowded plot , 0 to 40 deg --
80240th

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Same as above, with the traces separated --
80240separatedth

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