One of the side-effects that come along with the holey brace is that it changes the standing wave structure of the box. Without the brace, you would have 1 standing wave = the length of the black arrow. The brace, with its holes, now distributes the energy across 3 standing waves, black, blue, red. The shorter ones become easier to absorb with the damping material.
dave
dave
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Hi dave,
Your bracing is great, but seems complicated to make. They may be made by CNC tooling.
Tony.
Your bracing is great, but seems complicated to make. They may be made by CNC tooling.
Tony.
A brace dead centre is not very effective at killing the 1st panel mode. As you can see in the sketch, a centrally placed brace clamps the panel at the null of many modes & thius can encourage them.
One of the rules of bracing is: A brace should divide a panel into unequal sub-panels.
In addition to the vertical driver brace, cross-braces are also recommended.
dave
Chris can confirm, but braces take as much work as whole rest of the cabinet.
The brace from the back of the driver to the back of the box in particular helps the downward dynamic range.
dave
I'm going to disagree with you there (to a minor extent); they should bring a slight benefit as they're near the terminus, where there's a reasonable amount of stress. Very small, no argument, but probably better than nothing; more useful in holding up the damping of course.
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Is there an advantage to using the 'hole' bracing as opposed to window type bracing(square or rectangular openings)? It seems like the window type would offer less of an obstruction to air movement and wouldn't affect the cubic footage of the enclosure as much. Of course the openings of the bracings would be rounded over just like the circular openings. Any thoughts?
Depends how much meat you leave. The circle does leave a stronger brace (it follows after "the arch"). The orientation of the brace is important. These braces are vertical which do not impede air flow (any side to side is a bonus as illustrated in post #144).
dave
I guess I'm reviving this thread, and boy I have a lot of questions. I'm a pretty serious audio nut that is lucky enough to have his own listening room. It's not nearly as large as I wish (13 x 15) but I've concentrated on killing first reflections and sucking up as much bass as possible with traps. Imaging with almost any competent spkrs is very good.
I've been subscribed to quite a few FR threads and am at the point of ordering a couple MA drivers to get some first hand impressions. I'm leaning very hard toward the 12s as they are able to move more air, and being 60 yrs old, my hearing range is limited to about 13khz these days. The 10.2s seem to be in higher regard these days but I guess I'm stuck in the "bigger is better" camp.
With my music choices of mostly blues and jazz of all types, plus some rock and classical, plus my desire to "load the room" excessively from time to time, it just seems to point me towards the 12s in Super Pensils.
I guess my main question is will I be asking too much of FRs to start with?
I've been subscribed to quite a few FR threads and am at the point of ordering a couple MA drivers to get some first hand impressions. I'm leaning very hard toward the 12s as they are able to move more air, and being 60 yrs old, my hearing range is limited to about 13khz these days. The 10.2s seem to be in higher regard these days but I guess I'm stuck in the "bigger is better" camp.
With my music choices of mostly blues and jazz of all types, plus some rock and classical, plus my desire to "load the room" excessively from time to time, it just seems to point me towards the 12s in Super Pensils.
I guess my main question is will I be asking too much of FRs to start with?
in no particular order;
no, I don't think your asking too much of a decent FR system
the room you describe is small enough that you might well find the smaller Alp7 or 10.2 quite satisfactory for both sensitivity/SPL and bass extension - and the required enclosures are somewhat smaller if floorspace is an issue
.
I appreciate the reply. Footprint really isn't an issue at all, no WAF to deal with, I married a saint. My second spkr system is a pr of 30" wide baffles, a totally different type of sound, but I like them.
I have been urged to try the 10.2s by another member, and the baffle width of the Super Pensils does put me off a little with respect to imaging. I was wondering if there wasn't another way to achieve their goals without changing it from the original Pensil 12 design. A huge radius cut on the side corners might be an option.
I realize there are many more advanced cab designs I can try, and I'm a fairly competent woodworker so starting with the right driver is the biggest deal for me at this point. Are there any specific designs that you might recommend?
Sorry for rambling.
Thanks, Bill
I have been urged to try the 10.2s by another member, and the baffle width of the Super Pensils does put me off a little with respect to imaging. I was wondering if there wasn't another way to achieve their goals without changing it from the original Pensil 12 design. A huge radius cut on the side corners might be an option.
I realize there are many more advanced cab designs I can try, and I'm a fairly competent woodworker so starting with the right driver is the biggest deal for me at this point. Are there any specific designs that you might recommend?
Sorry for rambling.
Thanks, Bill
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