Greetings, fellow bass nuts. Some of you may remember me from this
thread, which chronicles the progress of my very first tapped horn project. Even before I was finished with that one, I always intended to go back and do it all over again; improving on the design as I better learned from my experience with that first project what made for a good tapped horn.
After several months of work, with a lot of help from many other people, this thread is the result. I was going to wait on this until I actually got started the building phase, but I think I'll post this early now that the drivers have been ordered.
My original goals were to replicate the Tang Band horn mentioned above in a smaller package with greater output and greater bandwidth. This here design isn't the best I can do for these woofers, but folding a more complex design into a package I can build is something that I'm still working on. So, I tried to keep this as simple as possible.
Here's what I wanted from this design:
- 16-100Hz at 115dB in half space, 120dB+ in room at LP
- less than 550L before materials
- shallow, to enable better use as a riser
Other than that, I didn't really have too many other limits on it. The result of all my work is that I have a 533L design here before materials that will do 113dB in half space at 16Hz with 300W before reaching Xmax. Based on experience with my last TH project, it will have no trouble at all sustaining 120 at LP, because that horn already hits 120 at LP. It will also likely handle 600W+ before the woofers get into any kind of excursion trouble, so I'm going to push it at 2 ohms off one channel of my RMX-1850HD. It may or may not be highpassed... we'll see. It has the kind of headroom my old horn can only dream about, so I may not need to.
A drawing of the final Sketchup file is below, and my Hornresp file is attached. As drawn, it's 79x42x13.2." Big, but very shallow. I could fit four of these, two in front of two, behind my screen if I needed to. Building won't start until the snow goes away... I can't do any woodworking outside until it does, and there's no room inside.
Materials needed will include three sheets of 3/4" plywood. The four sheets needed for the last one was really too much. The throat will be braced, but other than that I won't be doing much extra bracing due to the shallow depth. I'll be picking up several 1" dowels, however... if I feel like the horn's gonna need the extra bracing, I'll use them. PL Premium will again be used - two large tubes will do. The open space in front of the throat and above the mouth will house a Speakon, and two of the horn's folds will get a thin lining of polyfill much in the same vein as the last horn I built.
I'll post a diagram with the actual plans for construction and/or the Sketchup file once I start building. I'm reluctant to let anyone try my unproven design before I know what it's like in the flesh.
Hornresp screenshots with 350W in, half space, excursion peaking at a safe 20mm above the corner: