Does anybody know
Does anybody know
Last edited by cradeldorf; November 15th, 2012 at 04:12 AM.

It won't expand all frequencies. Each length will produce a peak at the frequency it's tuned for. So to start, your graph looks like a roller coaster. Then, TONS of phase cancellations from time delays...sound in air is roughly 1000 ft/sec so every foot is a millisecond delay or so.
Tuning is used to produce a peak where your woofer rolls off, or rather just below. The trade for the response is phase issues. relatively minor with one but multiplied by this design.
Back loading horns were abandoned mostly due to phase issues. They are still used as Pro woofs, but operated below the band produced from the front of the cone.
Your neighbors called. They like your music.

Your homework gets a gold star.
Buy a copy- I can't recommend it enough...read it several times you will understand more each time.
http://www.amazon.com/gp/offer-listi...condition=used
101 level explanations and many cool vintage plans, The other recommended book is Abe Cohen's. But for bang/buck ratio, $14.95 is a steal, and free ship.
Last edited by Old Guy; February 24th, 2012 at 05:27 AM.
Your neighbors called. They like your music.

If you wanna know more about the author...
1960'S ENCLOSURE PLANS
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Your neighbors called. They like your music.
I'm a bit enamored with that photo of the engineer posing in the anechoic chamber.If you wanna know more about the author...
I'm pretty sure he's just posing with that 604/605. But, those oddly placed fiberglass bats tells me they were doing some very meticulous and precise damping of small reflections. That's some pretty "micrometer" fine tweaking, i don't think too many other companies were that far along at that time. Impressive!
That book sells for quite a bit on ebay. I've got a copy that was given to me when I was about 14. A neighbor gave it to me. It had been his sons, and was left behind when the son went off to college.....or something like that. That was my first exposure to Altec Lansing.
Audio_by_Goodwill
Michigan, USA
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