BillFitzmaurice.info

Check Penn Elcom.

I’m trying to calculate power needs for the OT8’s. Does the compression driver post crossover alter the impedance load on the amp? Or is it going to be a flat 4 or 16 depending on wiring? I’m targeting feeding each OT8 400 watts to be split between the 8’s. There's no such thing as flat impedance w...

How much power goes to the compression driver? It gets the same voltage, but as frequencies rise, the impedance does too....meaning the wattage at the driver is much lower than the woofer sees. Not quite. What happens is that the voltage is the same but power density decreases by 3dB per octave wit...

jHands wrote: ↑Wed Nov 26, 2025 12:09 pm If I were to switch to a single, larger sub, that can lay on its side, does the vent mouth need to face the crowd?

Bill Fitzmaurice wrote: ↑Fri Nov 21, 2025 9:32 am

jHands wrote: ↑Fri Nov 21, 2025 12:16 am With regards to the T48, can it be used horizontally?

Like any and all subwoofers it can face in any direction, so long as the horn mouth isn't blocked.

Sure, provided you have the power to drive them with. If you're using a 12v battery or two you probably don't. An E-Bike probably doesn't have the power to pull two subs either.

Why you need two subs.

There's no need to do that, as the radiation pattern of subs is 360 degrees on both the vertical and horizontal, and content below 100 Hz is the same in both the left and right channels.

Don't give your work away. Also don't rent out anything that you don't mind having destroyed. Rent your services as a DJ or live sound engineer along with your gear. A website is a must, and they're not expensive.

I stopped gigging five years ago as my drummer is no longer able to play; we've been together since 1983. Still have all my gear, just in case.

jHands wrote: ↑Fri Nov 21, 2025 12:16 am With regards to the T48, can it be used horizontally?

Like any and all subwoofers it can face in any direction, so long as the horn mouth isn't blocked.

Knowing your location would help. You need to update your profile.

A 24x24x48 T48 comes in closer to 90 pounds, depending on the driver. That's still far less than comparable commercial subs. A Danley TH-112 is 138 pounds. It's also $4k.

If I was there I could explain it, but there's only so much I can do without actually being there. Beam forming is a thing, ask anyone who's been subjected to a Vox AC30 on axis at 110dB while someone thirty feet to either side can't hear the guitar.

They do not. Not enough builders have CNC to justify it.

Old Mike wrote: ↑Mon Nov 17, 2025 11:19 pm Will the design be available to us DIY people?

That's up to the manufacturer.