Midrange experiment with Auto sound panel deadener and high density acoustic felt..

With the aluminum top piece and leather(not shown), the midwoofer will be siting on seven total alternate layers of soft and hard. I guess overkill is better than underkill.
 

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Okay, finally closing in. One more test fitting because with six layers, all the holes need to line up. Anyway, here’s what it will look like with the decorative screw caps in place..
 

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To insure total isolation between front and back aluminum plates, high durometer rubber bushings are used for driver mounting. Nothing(That I can think of)is being left to chance..🙂
 

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My primary concern are the midbass drivers. Tweeters operate above anything that can excite a box resonance. But just in case, the tweeter is set directly onto sorbothane, so it’s own mounting plate creates its own CLD situation. It will also be completely mechanically isolated from from the midwoofer, which would otherwise be able to transmit resonances to the tweeter’s output in the same way it can transmit resonances to the cabinet itself in conventional situations.
 
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My planned crossover points will be 80 between the sub and the four bass drivers which will be crossed over to the mid-bass between 200 and 300hz depending on flatness and/or distortion measurements of the 4” drivers at 90db. The midbass and tweeter will be around 2khz, once again based on the type of measurements I’m getting with an 8th order LR. The key is to get the top cabinet to do as much of the critical midband as possible, since that is the reason I did this project to begin with🙂
 
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its really cool so far to see and think about your adventure. One thing to seek would be really good percussion recordings. Now days, YouTube videos of drumkit reviews often have well mixed and contoured multi-mike recordings. Some may be true stereo with much more room sound than close miking,

What is the little mid-tweet module on the other speaker in the picture above?
 
Had a little mishap while assembling the second speaker. While tightening one of the four baffle mounting screws, one of the anchor bolts stripped out of the wood because they weren’t designed for tightening down as hard as I need to for this type of design. Luckily I found some good four pronged t-nuts on amazon. In two days I’ll be back in business. I’ll at least be able to take a few measurements tomorrow
 
My primary concern are the midbass drivers. Tweeters operate above anything that can excite a box resonance. But just in case, the tweeter is set directly onto sorbothane, so it’s own mounting plate creates its own CLD situation. It will also be completely mechanically isolated from from the midwoofer, which would otherwise be able to transmit resonances to the tweeter’s output in the same way it can transmit resonances to the cabinet itself in conventional situations.

Midbass mechanical resonances through the baffle can not only affect the tweeter output, but of course can come back to affect the midbass driver as well. Very loud, out of time acoustic reflections within the cabinet come back to haunt the midbass too. All of this, plus box resonances can affect midrange and treble purity in a profound way. Hopefully my design objectives will have a large impact on all or most of those issues.
 
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First midbass measurements, 200hz to 2khz and no equalization. Interesting to say the least..
 

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