jbell's set of four tapped horns

[polviggen]

according to the sim, it seems that the folded horn specs i came up limit the cone excursion alot more compared to the tapped horn.

the tapped horn runs out of xmax at 40hz and 40V
the frontloaded at 65hz and 60V, which gives it +5db of extra max spl.

now let's fire up autocad and see if i can come up with something easy enough to built i want to built this, measure it and compare with the th, which is already very impressive on kick drum.

i wanted to edit my previous post but the button is gone, is there a time limit to that ?

[David_Web]

"It'd be a REALLY INTERESTING topic to find the answer to... Why is a TH directional? "

Any numbers on how directional it is?
What frequency, how wide...

[davygrvy]

My guess: phase based. Where the rear wavefront from the horn meets the front wavefront from the driver causes a lobe or bubble pointing the resultant. It takes two signals to steer, so I'm guessing interaction between front of the driver with the rear.

[jbell]

Originally Posted by Thijs666

Outside would be great! Assuming you use the 3015LF from the Omni15, all cabs are loaded with the same speaker, so it's going to be a pretty fair comparison.

This weekend is a bit busy for me, but can we do it next weekend, let's say saturday afternoon?


28V, Paul, how close are your neighbours, 'cause that's gonna be loud .

Looking at the charts, I expect that too, jbell. I am thinking about measuring methods now. The only thing I have that is calibrated for SPL, is my Behringer DEQ2496 with the ECM8000 measurement mic. But I have various options for measuring (relative) frequency curves. Of course I can measure 100Hz on the DEQ2496 and then adjust the mic preamp for the same level in SMAART or something .

What's the best place to put the mic? I'm thinking ground plain or 1 inch from the ground ...

This testing ever happen? I'm interested to know how they compared.
I also ran across another little bit of info related to this, seems BF has a comment on how the 'sound' should differ, one to the other, so a subjective listening test would probably be appropriate as well.

BillFitzmaurice.net - View topic - OT112/212 vs JTR Triple 12

[polviggen]

not yet, bad luck with the weather here, too much rain and wind.
it's still storming out here as i'm typing this.

got a behringer dcx2486 for crossing over btw, time to give that tapped horn a good testdrive

[jbell]

Originally Posted by polviggen

not yet, bad luck with the weather here, too much rain and wind.
it's still storming out here as i'm typing this.

got a behringer dcx2486 for crossing over btw, time to give that tapped horn a good testdrive

LR48@38hz HP, LR24@90hzLP would be a good place to start. (90hz LP just shaves a little off of the 100hz bump in response, and gives you a nice flat response from 40-100, with a couple db bump up at 40... that whole equal-loudness curve thing...)

have fun

[polviggen]

what's the advantage on using LR vs butterworth ?

[davygrvy]

An LR filter tends to sum better.

[polviggen]

i see, so for the highpass of the sub butterworth has the advantage of a steeper slope ?

[jbell]

If I understand your comment about slopes correctly -- slopes are same. 48db butterworth is same slope as 48db LR.

However, LR is flat at crossover freq, butterworth has a 3db bump as davy's chart shows.

I really don't like the sound, even spaced apart to eliminate some bump of the butterworth slopes in the dcx2496. (aka, 90hz24but LP sub and 120hz24but HP top doesn't sound as good to me as even 100hz24LR LP sub and 100hz 24LR HP top) Now, I could just be crazy on this one.. but I don't use the butterworth slopes for any reason on a dcx.

For a good place to start, I'd set sub at 90hzLR24 LP (only because there is a slight bump at 100hz for the TH) and top at 100hzLR24 HP. That should give you a really nice transition. (at least it did for me)