I have a Peerless 830875 and Seas 27TDFC mounted in a partsexpress 0.25 cubic feet cabinet (half stuffed). Both are amplified using my regular stereo setup with the DEQ 2496 acting as a two way crossover. I have been testing with just one speaker before committing to hardware component values (no more budget left for a DCX).
The woofer has a 24 db/oct lowpass filter at 1500 Hz, and a 12 db/oct highpass filter at 85 Hz (combined with the natural rolloff to make 24 db/oct). The subs I already have will be crossed over to the monitors at 85 Hz. I used a shelving 6db/oct lowpass filter for baffle step compensation (7.5" baffle), with a 3db gain at 560 Hz, somewhere I read a formula that says thats where to put the correction.
The tweeter has a 24 db/oct highpass filter at 1500 Hz. The speaker sounds too bright, as many have noted for the Seas 27TDFC, so I put in a shelving 6db/oct filter with a loss of 2.5 db, and a frequency of 5140 hz. The settings for the shelving filters are not exactly intuitive, but might make more sense if you have a DEQ.
The tweeter has a 1 db attenuation relative to the woofer (it would need more attenuation, but the shelving filter attenuates it also). The tweeter has a 0.18 ms delay relative to the woofer. The drivers are surface mounted, with 1/8" adhesive backed felt covering the surrounding baffle.
Please make any comments on the design. Objective measurement has not worked for me for anything but extreme nearfield. I will finalize the crossover using linkwitz' filter circuits, but mounted on a breadboard for now, and using a mouser regulated power supply for the opamps.
Thanks,
Lee
The woofer has a 24 db/oct lowpass filter at 1500 Hz, and a 12 db/oct highpass filter at 85 Hz (combined with the natural rolloff to make 24 db/oct). The subs I already have will be crossed over to the monitors at 85 Hz. I used a shelving 6db/oct lowpass filter for baffle step compensation (7.5" baffle), with a 3db gain at 560 Hz, somewhere I read a formula that says thats where to put the correction.
The tweeter has a 24 db/oct highpass filter at 1500 Hz. The speaker sounds too bright, as many have noted for the Seas 27TDFC, so I put in a shelving 6db/oct filter with a loss of 2.5 db, and a frequency of 5140 hz. The settings for the shelving filters are not exactly intuitive, but might make more sense if you have a DEQ.
The tweeter has a 1 db attenuation relative to the woofer (it would need more attenuation, but the shelving filter attenuates it also). The tweeter has a 0.18 ms delay relative to the woofer. The drivers are surface mounted, with 1/8" adhesive backed felt covering the surrounding baffle.
Please make any comments on the design. Objective measurement has not worked for me for anything but extreme nearfield. I will finalize the crossover using linkwitz' filter circuits, but mounted on a breadboard for now, and using a mouser regulated power supply for the opamps.
Thanks,
Lee