I know there are plenty of systems being listened to by members here with either 2360 or 2365 CD horns with 2446j drivers, and I am about to join that crowd with my own pair. Current bottom will be done with already running GPA-Altec 515-8LF 16 inchers in large scoop type enclosures with electronic EQ. Custom electronic crossover, 4th order Linquitz Riley is sweepable. Upper power is 2A3 push pull tubes of about 15 watts, or BAT VK-60 [ way too much power ] . I have 2241g drivers that will eventually get enclosures and become the lower section for these horns.
I have carefully measured the impedance of the horn/driver system, and acoustic output outdoors facing straight up. From that I have done my own network that has a broad Q dip of about 5 sB between 450 Hz and 7KHz, centering in the 1 to 2 KHz region. Above 7K I put in a 4 dB tilt up extending all the way. Given the nature of the horn throat at 2" and the limited frequency range of the Ti diahram in the 2446j, I know it is not advisable to EQ too much in attempt to force the upper octave to be near flat, but a gentle nudge in that direction seems to be accaptable, given the comments I have looked at over the past few years. I have not yet built my network, just used modeling software to design the filters to arrive a the curve I desire. I WILL publish it here good or bad, shortly, so that we can all learn as a comminity and you guys can comment [ I need to put photos of the pages into Photobucket to get them shared here, will do very soon] . I am interested in learning what other people have done with these horn and driver to effect a CD compensation, and if anyone bothers to deal with the slight hump in the 1 to 7 K region.
Last year I found and read a JBL document that had a number of suggested schematics that had some EQ lift at the top, but I have lost the link, or if I ever had it, the .pdf. It was very long handbook or app note format, not a data sheet/support document for a specific component like a JBL passive crossover. I have re-found the cinema installers manual, but it just has theory of acoustics and how to make good sound in the audience, nothing about engineering a speaker system to do that with. If anyone recalls a handbook or contracters manual that discusses CD EQ and has schematics, I would appreciate a link... I just wasted 3 hours looking all over here and the internet for something and came up zero so far.
Please drop in with your passive EQ solutions. Also interested in EQ if you have installed Be from Truextant...which are flatter in the mid and higher up, as well as less colored. They are not in my immediate future, but farther out, yes.
Cheers
Jennifer
Here is the hand drawn plot of the impedance and the output....I had impedance in WT-2, and output in a borrowed AP System 2, so to see the data together I just made this sketch....
This would be my desired curve to dip the bulge in the upper mids, and lift the highs a little bit
This is my proposed network. Because the actual impedances are bumpy up and down, I just estimated the average over the band area if interest to run the calculations...
http://www.mh-audio.nl/spk_calc.asp This fellow has a nice website for doing calcs..It IS a good place to become familiar with if you DIY or even if you do design for a living, and need some calcs for which you don't have the specific program.
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