macaltec
Metal Master
That was very helpful and informative in a simple kinda way. I can work it out with all the info I have collected. Thank you.
Altec Horn Single Cell dimensions/patterns
- Thread starter macaltec
- Start date
BillWojo
Addicted Member
If the Altec horns are exponential, than just some basic measurements (Length of horn tube and front and rear openings) combined with the simple math in that article will yield you very nice curves for the sides is all I was alluding to.
I to do metal work. I forget the name of it but there is a simple metal shear that would be ideal to cut all the side pieces out after they are scribed.
BillWojo
I to do metal work. I forget the name of it but there is a simple metal shear that would be ideal to cut all the side pieces out after they are scribed.
BillWojo
macaltec
Metal Master
I realize what you were saying. I had tried to read up on the design and always ended up looking and equations that made my head spin. This new info was very refreshing. I will draw up a flat pattern and have the pieces laser cut, then I can preshape the curve a bit and TIG weld the edges.
macaltec
Metal Master
I saw that. I can just draw it out and scale it in Solidworks. I will post some pics after I get it modeled. Many many thanks again. This was the key bit of info I was looking for.
604man
Super Member
Let us know how it turns out ;-)
macaltec
Metal Master
Something aint stirrin' the Kool Aid. With the length I have for an individual cell by the time I get to the large end of the flare I have a phenominally big horn. I have questioned the varying lengths I have seen online. Just for giggles someone chime in with what you think "cross section" means.
gdmoore28
Super Member
Did the Altec measurement include the horn throat? Your's does not.
By the time you add the throat, your's will be 16."
GeeDeeEmm
bowtie427ss
Lunatic Member
18 cells, 300hz, 3 rows of 6 cells each, 27-1/2 inches deep. The 500hz 1005 horn that the OP is attempting to fax is about 1/2 the overall physical size. 1803's are HUGE.
The correct throat is 4-3/4 inches long, and is a separate part identified by it's own part number.
The part that the small end of the cells is sweat to is called the "collector". Acoustically, it's the most critical part of a multicell horn, and where most DIYers will fall down. Where each cell terminates inside the collector forms an arc equal to the arc formed by the front of the horn. So, the distance to the flange of the collector, and therefore the "throat" varies depending which cells you are measuring.
What the OP really needs to do this right, is a 1005 in his hands.
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gdmoore28
Super Member
Heck, yes, that's what I meant to say, but my crusty brain hasn't been firing on all cylinders the last few days. Thanks for correcting me. We're venturing into unknown territory for me (so, what else is new?).
So, once the throat is attached, won't that bring the length into line?
GeeDeeEmm
bowtie427ss
Lunatic Member
In a "close enough" kinda way given the time period, and the original application they were designed for. Times and technology change.
In their day, there was really nothing that could even come close to the acoustic output, throw, and dispersion of a quad of 288's bolted up to a single 1803. Again, times and technology change.
I can argue for either camp.
What they do well, they do really well. It's a happy balance for some people.
What they don't do well, they never will. Many enthusiasts who first shout high praise from the rooftops will soon enough move on to greener(hopefully) pastures.
I wanted to love multicells in a hifi set-up, i tried more than once. I could just never get my ears to lie to my heart.
.
Yep, 1803's are massive. And a bit too beautiful. The mention of that thread was it would be closely associated to this one. For example the way he built his collector is a good one worth noting.
http://www.diyaudio.com/forums/multi-way/136964-construction-multicell-horn-25.html
http://www.diyaudio.com/forums/multi-way/136964-construction-multicell-horn-25.html
BillWojo
Addicted Member
Not even the 808H horn? That's actually good news because I could never afford them anyway. But man, do they look cool!
BillWojo
bowtie427ss
Lunatic Member
My multicell experience has been with large format only. The 808 with an 802 will enjoy an upward shift in frequency response which will give it HF extension that most large format horn/drivers simply cannot do. This much we know without listening. You'll see a lot of folks trying to incorporate tweeters with their big multicells along the journey with them.
They're also reasonably sized, which i think plays a significant role in their demand. I also trust folks like Joe who tell us they sound splendid which helps further push their value skyward.
