Two-way W/Heil air motion TX

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Trying to come-up with a great two-way & found out that makes a replacement 15" driver for the Realistic Mach One. I sold the Mach one when I worked for RS a long time ago...Now we combine the two particular loudspeakers from the past & create something very different.
Running the numbers for the 15" 'Mach One'.....I just knew it was going to be ideal for sealed systems.& I got 34.92 for EBP.........right in the range for sealed. That was to be expected as the original was a mere Twenty five or so inches high, maybe seventeen inches wide & only...say Fourteen inches deep.
So when I crunched the numbers for the "perfect" .707 I came up with 20.35 cubic feet......How did they squeeze it down so far? Pushing towards 1.0 Qtc way under-damped. So I would have a enclosure 26" wide,32" deep,41" High. Trying for the narrow Mega-tower look. With the Heil mounted on top,I could set it 'back' on the enclosure trying to correct any phase shifting.
The cross-over will be tricky as the overlap is very narrow.
Any ideas???????????



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Joined 2006
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Hello Richard - P10 and Chris B did something along these lines a few years back - but they used a now defunct 9 inch Fostex for the woofer. Scroll down a bit and you will see a tall speaker similar to what you are talking about - and next to it a box that uses a larger driver but without a AMT.

planet_10 hifi

Despite what they say I would be careful about crossing the AMT lower than 2 kHz - I cross mine at 6 kHz 1st order with a 6.8 cap and use them as tweeters. The AMT1's I have were made in the 70's tho - so the new ones might work better.

BTW - what is the part number you are using for the replacement woofer?


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I used the Big Heil on my three way system. I have an active crossover and could roll out the mids and bring the Heils down to meet the woofs. They say they can go down to 800hz, but anything under 2K is REALLY thin. Even from 2K on up, IMHO, is REALLY thin compared to my 350hz round Edgarhorns. I think the Heil is the best "tweeter" available.....but that is just me. If you can, try to listen to them before commiting. They seem to have a "love em/hate em" effect on people.
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