S
swarfrat
Guest
So I started looking for a FRFR, but I need REALLY FRFR, as it needs to do triple duty as bass and electronic drum monitor. I was shooting for about 115db (drums are extremely transient to say the least), and a -3db of 45 Hz. I looked at commercial offerings, and was disappointed - even the 215's often have cutoffs in the low 60's, and virtually ALL of even mid-cost drivers are excursion limited. It was looking like a Fearful cab was going to be the only real solution (DIY and $$$$ at the same time).
Mayfly got me stirred up with his Eminence Beta 8CX coax monitors, but I needed solid bass a lot deeper than most commercial offerings. (I haven't sampled it yet, but my 32" Bass drum has an honest to goodness measured fundamental of 30 Hz, and it's tuned WAY above lowest possible pitch. I love having that kind of whomp available and it still plays like it has some tension on it!)
The Beta 8CX ain't a bad looking driver, but it's excursion limited below 100 Hz. However it can make a fabulous midrange PA driver. The Pyle PDW15125 only costs $100, and in a 6.5 ft^3 box tuned to 33 Hz, it'll do 118db at the excursion limit (which is only a tiny dip BTW, it's a very good match between the excursion limits and thermal power limits), and yield a -3db point of 33 Hz. (Most commercial PA cabs advertise the -10db limit, which is WAY down.)
The design so far is the 15 in a 6.5ft^3 box, tuned to 33 Hz. With the Beta CX in a 0.75ft^3 sealed box (Q=0.5, which is critically damped - we don't need bass from the 8CX in this app. The bigger than normal box size also helped dispersing the rear wave - some internal baffling will be installed for this as well. I'll be using the APT-50 Super Tweeter on that 8CX, crossed over @ 2.5k. Together we're looking at a 7.5ft^3 or so enclosure, or roughly 30" x 24" x 18" box.
I debated about making the 8CX detachable, as I could take a much smaller box for guitar only stuff - as long as the excursion limits are observed (113db @ 100 Hz, -3db @ 70 Hz or so, depending on the enclosure) but I didnt really like any of the detachable sketches I came up with, and the overall box /weight is smaller with the built in.
So it's a biamped system, 230W on the 15, and 200w on the Beta 8CX/Horn, -3db @ 33 Hz, Max SPL 118db @ 1m. Since it's biamp, I was planning to use a Behringer iNuke NU3000DSP for power amp, crossover, and limiting. Also, because of the biamp requirement, I was contemplating integrating the amp into the cabinet.
Anyway - I did order my parts today. Got a couple house projects coming up so it'll likely sit until the toy budget recharges enough for the amp. Pictures once it starts happening.
Mayfly got me stirred up with his Eminence Beta 8CX coax monitors, but I needed solid bass a lot deeper than most commercial offerings. (I haven't sampled it yet, but my 32" Bass drum has an honest to goodness measured fundamental of 30 Hz, and it's tuned WAY above lowest possible pitch. I love having that kind of whomp available and it still plays like it has some tension on it!)
The Beta 8CX ain't a bad looking driver, but it's excursion limited below 100 Hz. However it can make a fabulous midrange PA driver. The Pyle PDW15125 only costs $100, and in a 6.5 ft^3 box tuned to 33 Hz, it'll do 118db at the excursion limit (which is only a tiny dip BTW, it's a very good match between the excursion limits and thermal power limits), and yield a -3db point of 33 Hz. (Most commercial PA cabs advertise the -10db limit, which is WAY down.)
The design so far is the 15 in a 6.5ft^3 box, tuned to 33 Hz. With the Beta CX in a 0.75ft^3 sealed box (Q=0.5, which is critically damped - we don't need bass from the 8CX in this app. The bigger than normal box size also helped dispersing the rear wave - some internal baffling will be installed for this as well. I'll be using the APT-50 Super Tweeter on that 8CX, crossed over @ 2.5k. Together we're looking at a 7.5ft^3 or so enclosure, or roughly 30" x 24" x 18" box.
I debated about making the 8CX detachable, as I could take a much smaller box for guitar only stuff - as long as the excursion limits are observed (113db @ 100 Hz, -3db @ 70 Hz or so, depending on the enclosure) but I didnt really like any of the detachable sketches I came up with, and the overall box /weight is smaller with the built in.
So it's a biamped system, 230W on the 15, and 200w on the Beta 8CX/Horn, -3db @ 33 Hz, Max SPL 118db @ 1m. Since it's biamp, I was planning to use a Behringer iNuke NU3000DSP for power amp, crossover, and limiting. Also, because of the biamp requirement, I was contemplating integrating the amp into the cabinet.
Anyway - I did order my parts today. Got a couple house projects coming up so it'll likely sit until the toy budget recharges enough for the amp. Pictures once it starts happening.
