![]() READ MORE: Best speakers to buy in 2022: 11 best small studio monitorsĭigital filters and equalisers provide audio solutions due to their capability to operate without introducing significant phase shift, which is why you’ll see some processors refer to linear or minimum phase.There’s little space for bass traps, for example, in rented rooms and temporary accommodation. Wiser money is put into in-the-room acoustic solutions but these are not always possible. Unfortunately, analogue equalisers introduce phase shift, a frequency-specific delay, and this can make matters worse. Fuzzmeasure is a great Macintosh program for speaker and audio measurements.Ever since monitor speakers were first placed in a room for audio-production purposes, people have employed equalisers to compensate for what they perceived as impediments to a clear sonic picture. ![]() I’ve since fixed my problem and the Fuzzmeasure readings and my software readings agree very well. Update: The smoothness is due to over-driving my input signal, which was not obvious to me. But the crossover information looks very similar. Note the insane smoothness of the Jordan driver (compare this to every other measurement you’ve ever seen of the Jordan). The output of Fuzzmeasure is shown below. The Jordan is still breaking in, and I’ll lengthen the port to tune it to about 45Hz when the Fs of the Jordan drops. The red woofer trace shows the current port tuning at about 55Hz. The second plot shows the port contribution and woofer null with close microphone placement at the driver cone and port exit. The first plot is the impulse response, woofer and tweeter response, and the null from the tweeter polarity reversal. But the windowing process also rolls off the bass response, so anything below about 300Hz is artificially rolled off on the plots below. Note that my impulse response is “windowed ” to eliminate the room response. Here is the speaker response as measured with my software. My code also matches the impulse response of Loudspeaker Lab. My program is also slick and works the way I want it to, and I have control and understanding of the processing the program does. Update: I was over-driving my Fuzzmeasure measurements and that causes the flat-top readings shown below. Small changes in the crossover show up in the response. The drivers are in no way as flat as it makes them out to be, but the crossover region seems to be represented accurately. Fuzzmeasure is a very slick and easy to use program, but it seems to show a rosy picture of the response. I also used software of my own design which uses MLS sequences to calculate the driver impulse response. I used Fuzzmeasure, which uses a swept-sine deconvolution to calculate the impulse response. I used two different software suites to do the driver response measurement. I used my computer and an external USB soundcard with my impedance bridge and microphone pre-amplifier, a Panasonic WM-61A electret microphone capsule, and my modified Dyna SCA-35 to drive the speaker as the basis of the measurement hardware to design the crossover. ![]() The woofer crossover is a butterworth topology, and the tweeter circuit is somewhat of an unknown that compliments the response of the woofer. I settled on a 3rd order crossover (electrical) for both the woofer and tweeter. 4th order filters worked pretty well, but the parts count was crazy, and the sound seemed somewhat pinched off and odd sounding in the crossover region. After messing with 2nd order crossovers, it was pretty obvious that it wasn’t rolling the drivers off fast enough. So in order to get a reasonable crossover rate and not have a huge upper midrange muddying region where both drivers are contributing, the drivers need to be crossed over pretty hard. The jordan is designed to not roll off in the treble, and the Vifa XT-25 doesn’t seem to know it’s tweeter. The beginning of this project can be seen here: Where there are pictures of the cabinets being routed, and the drivers mounted. Finally, the deciding factor: I had a pair of them. The character of the XT-25 also matches the Jordan driver quite nicely. The crossover point is nice and high, so the XT-25 won’t be stressed. I considered a ribbon, but I kept coming back to the Vifa XT-25 as a great mate for the Jordan. But not any old dome tweeter would do the Jordan justice. To take the good stuff from the Jordan and not get the bad, I decided to mate it up with a tweeter. The bass response, while not window-rattling, is really impressive for a 5.5″ driver. Below about 4KHz, the driver has a clarity and an uncolored response that is very impressive. The Jordan JX-92 is a great little driver, but has some raggedness in the upper frequencies.
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