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(Scroll sideways to see entire graphic) Quick and dirty pink noise test. Pink noise is less useful for testing bass response so it is not shown. Since the test signal aready decreases by 3dB/oct. the treble roll-off is less than it would seem from this graph.

This test was done after modifying the original crossover for flat treble response per Linkwitz's suggestion in response to my request. He designed the original crossover to roll of the high frequency response for "spectral balance" due to the speaker's limited bass response without the EQ. The modification consists of removing the 0.3mH coil (the small bare wire coil seen in the earlier photo), changing the 0.28mH coil to 0.27mH (by simply removing a few turns), and replacing the 0.3mH coil with a 1.2µH cap (three .33µH and one .22µH in parallel) and a 10 ohm resistor in series, then wired in parallel just ahead of the tweeter.

This is a very good result! There are no large dips or peaks. With some experimentation in placement to minimize room effects on bass response the subjective impression is of a neutral, very transparent system. I get good bass down to 40Hz. One could easily spend US$2000 and not surpass the quality of these. I think they could hold their own aganst the best two-way small monitors.

For the test I used the DIY test mic detailed on Linkwitz' site, with a cheap mic preamp kit from Parts Express, and a shareware spectrum analyzer program on my Mac. I couldn't get the entire frequency range in one window on the analyzer, so I spliced the graphs from two tests (250Hz—2.2kHz and 1.8kHz—22kHz) together using the red line at 2kHz to line them up for this graphic.