Here are the pictures of my new all-dipole system. Both channels are ready now and I am working on the active crossover, so I have no idea how this monster actually sounds. Both towers in each channel stand at 76.5 inches tall.

and

The midrange baffle has four 10-inch drivers; - they are SS25W8565 wired in the series-parallel manner. The midrange baffle is 14 inches wide with 3 inch wings folding back. The drivers are held with the back spine, so no bolts are used.

The woofers are standard and well-known Phoenix design from S. Linkwitz with Peerless 12-inch XLS 830500 drivers for a total of 4 drivers per channel. Here the view from the back,

The main RD-75 baffle is a curved and sloping affair. The shape was influenced by the research done by John Wittaker and the article by Tom Pirazella. It is 24 inches at the bottom and 18 inches on top counting the curved part. The straight part of the baffle is one-sided trapezoid with 18 inches on the bottom and 12 inches on top. The RD-95 baffle has no sharp edges anywhere in an effort to minimize the diffraction effects.

Well the pictures are not all that great, but they give an idea of what the system is. It took more then a year to build this and it is huge. I somehow did not realize how big it was going to be as I was building it.

I intend to use my homemade amps to power the system. I have on hand 4 stereo units that can deliver a clean 500 watts into 4 ohms per channel. Interestingly enough I am also looking at the digital pro-crossovers. The Behringer DCX2496 product is scheduled to appear sometime this summer and it is looking particularly attractive with 24-bit capability and lots of useful features, - all the cost of $350US. So, who knows, by the time I am done with my analog circuit I may have this Behringer box.

The crossover points for the system are 70 and 300 Hz, all 4th order L-R. The notch filter for RD-75 is active and I am also using a fair amount of high frequency boost to EQ the RD-75 nearly flat up to 17 kHz. The boost is 10 dB and it is rising exponentially from at about 10 kHz (0 dB) and finishing at 20 kHz (+10 dB). The midrange is equalized with a 6 db/octave shelving lo-pass filter from 550 Hz and down to 20 Hz. It also has a notch of about 5 dB deep and 200 Hz wide at 320 Hz to account for the 25W driver basket resonance. Apparently there is a delay between the Phoenix woofers and the Midrange assembly. Since the midrange sits on top of the woofers I had to account for this delay electronically. So the Midrange crossover also has a delay circuit of 1.45 mS. All-in–all there are a lot of op-amps in this cross-over.

Well, let me know what you think of it.

Thanks,

Victor

and

The midrange baffle has four 10-inch drivers; - they are SS25W8565 wired in the series-parallel manner. The midrange baffle is 14 inches wide with 3 inch wings folding back. The drivers are held with the back spine, so no bolts are used.

The woofers are standard and well-known Phoenix design from S. Linkwitz with Peerless 12-inch XLS 830500 drivers for a total of 4 drivers per channel. Here the view from the back,

The main RD-75 baffle is a curved and sloping affair. The shape was influenced by the research done by John Wittaker and the article by Tom Pirazella. It is 24 inches at the bottom and 18 inches on top counting the curved part. The straight part of the baffle is one-sided trapezoid with 18 inches on the bottom and 12 inches on top. The RD-95 baffle has no sharp edges anywhere in an effort to minimize the diffraction effects.

Well the pictures are not all that great, but they give an idea of what the system is. It took more then a year to build this and it is huge. I somehow did not realize how big it was going to be as I was building it.

I intend to use my homemade amps to power the system. I have on hand 4 stereo units that can deliver a clean 500 watts into 4 ohms per channel. Interestingly enough I am also looking at the digital pro-crossovers. The Behringer DCX2496 product is scheduled to appear sometime this summer and it is looking particularly attractive with 24-bit capability and lots of useful features, - all the cost of $350US. So, who knows, by the time I am done with my analog circuit I may have this Behringer box.

The crossover points for the system are 70 and 300 Hz, all 4th order L-R. The notch filter for RD-75 is active and I am also using a fair amount of high frequency boost to EQ the RD-75 nearly flat up to 17 kHz. The boost is 10 dB and it is rising exponentially from at about 10 kHz (0 dB) and finishing at 20 kHz (+10 dB). The midrange is equalized with a 6 db/octave shelving lo-pass filter from 550 Hz and down to 20 Hz. It also has a notch of about 5 dB deep and 200 Hz wide at 320 Hz to account for the 25W driver basket resonance. Apparently there is a delay between the Phoenix woofers and the Midrange assembly. Since the midrange sits on top of the woofers I had to account for this delay electronically. So the Midrange crossover also has a delay circuit of 1.45 mS. All-in–all there are a lot of op-amps in this cross-over.

Well, let me know what you think of it.

Thanks,

Victor

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