I have a multiway project that suffers in the midrange sensitivity area because of my driver selection, the Dayton RS100P, at around 86dB. In dealing with this the MTM config seems appropriate but I understand it has its flaws. In minimizing CTC I have played around with a few scenarios using an offset tweeter. The first (left) is spaced using unmodified baskets. The subsequent two are increasing degrees of butchery to the baskets in order to pack them in; tweeter offset increasing as a result.
Is this worth doing, are they all good, all bad? I don't mind trying it out but it would be nice to get as close to mark as possible. BTW, the system is active with 3k Hz and 180Hz crossover points.
Is this worth doing, are they all good, all bad? I don't mind trying it out but it would be nice to get as close to mark as possible. BTW, the system is active with 3k Hz and 180Hz crossover points.
Ideally it depends on the desired polar response to choose drivers, design a baffle size/shape, driver layout, but the DIYer's reality is normally one of extreme compromise, so personally would choose easiest, most attractive and toe in as required to get the desired blending and use room treatment to fine tune if necessary.
"Easiest/most attractive"
Welp, hacking the edges off the basket will certainly not fall into that category 😆 I'm partial to the center version from the aesthetic perspective. If it all comes out the same in the wash, I'd probably try to get as close to that as possible with out any "special mods."
Welp, hacking the edges off the basket will certainly not fall into that category 😆 I'm partial to the center version from the aesthetic perspective. If it all comes out the same in the wash, I'd probably try to get as close to that as possible with out any "special mods."
Two 4" and a 180 Hz crossover (supposedly below baffle step?) seems less than ideal.
Why such a low crossover frequency?
And as this is going to be active the sensitivity should not be a problem, but Xmax and thermal limit will be.
Did you consider 2.5 way and a vertically aligned layout, for less horizontal lobing?
Why such a low crossover frequency?
And as this is going to be active the sensitivity should not be a problem, but Xmax and thermal limit will be.
Did you consider 2.5 way and a vertically aligned layout, for less horizontal lobing?
The logic is that 180Hz is a supposed maximum frequency that subwoofer directivity is not detected. The plan is to stuff a pair of opposing subs facing vertically behind the front baffle. In reading on the Dayton 4" my impression is they should go down that low. Doubling up on them lets me run them at lower stroke and still achieve decent SPL. The sensitivity issue is as much to do with being a low power system as it is anything. In terms of the Horizontal lobing, I can put the drivers in vert alignment no problem if need be. I'm just not sure at what point it becomes splitting hairs that I won't even notice.
The general idea is a compact bookshelf that hits F3 at 35Hz, doesn't require a traction motor to power it, and sounds decent AND goes loudish. Trying to get just over 100dB. In a 12 liter box.
Edit: Looking at Winisd, the 4" pair should do over 100dB at 1/3 xmax at around 30 watts with the 180Hz xover.
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Just make sure you account for baffle step and the sensitivity parameter by manufacturer given for 2pi space, not 4pi.
I mentioned "2.5 way" in my previous post - that should have been "3.5 way" of course, with a second mid compensating for baffle step.
Good luck!
For sure. Those RS100s can be used in a cute 2-way and get down to 55-60Hz, but obviously not loud. Two of them above 180Hz should be nice.
I highly recommend that you don't do a horizontal offset of the tweeter with a crossover set that high, you will have a very narrow sweet spot around the crossover frequency. I did something similar with a ribbon tweeter and 2 - 5" midbase drivers and the lobbing was horrible. The solution was to use a large dome and bring the crossover down to 1.5kHz, but that was still not ideal. Recommend that only one midbase driver plays up at the crossover frequency and all the drivers be in a vertical line.
Great suggestions, all.
The ingredients appear to be workable. On the baffle step issue, in light of the anabolic-tier amounts of EQ being employed on the subs, it shouldn't take too much additional massaging to iron out the dip from about 200-1k without even touching the crossovers (which do have provisions for step compensation).
With concerns over the horizontal window I went ahead and lined everything up accordingly 👍
The cheat code
The ingredients appear to be workable. On the baffle step issue, in light of the anabolic-tier amounts of EQ being employed on the subs, it shouldn't take too much additional massaging to iron out the dip from about 200-1k without even touching the crossovers (which do have provisions for step compensation).
With concerns over the horizontal window I went ahead and lined everything up accordingly 👍
The cheat code
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