Wooden 511

[djnagle]

I do agree about the new design, but I just love the 511, 311, 1505. Actually, I would love to do a 1505 out of a solid chunk of wood - real heavy but real cool but real$$$$$$$$.

[dhook17322]

I would be up for the A/B test. There currently is a 511B on ebay as buy now fairly cheap. The 511's I have do have the little rear fin in the throat area.
Agree on 1505's, but thay almost always fetch an insane price on ebay. Been watching 803's and 1003's, and they can be had fairly reasonable if you're patient. What the 515's go for is totally nuts though.

[thinking]

My suggestion would be to either invite the guys over that are going to do the computer/machine work, or go to the trouble of taking some more equipment with you so that you can set one up for them to listen to. After hearing the sound, they just might be interested in making a set for themselves, just for the oportunity of copying yours. After all, they're going to have the digital copy after you leave, but knowing what it's worth to them might be an incentive.

[djnagle]

Dave (dgwojo) has generously offered to lend me a 511 so we can start taking the surface measurements. Thank you Dave.

[raytclark]

Igor and all,

I'm getting in late on this thread, but I draw in SolidWorks/AutoCAD to pay the bills and have a pair of 511's. I would love to help on the project. (I don't have a 3d digitizer, so I would be creating a mockup based on an exponential curve that mimics the shape of the 511 and good ol' fashion measurements).

I also have looked at the throat section with a degree of question. (If someone can explain this transition it will be easier for me to draw). And also is the idea to replicate or improve on the 511? I can see doing both, but I also see the timeline increasing! (My personal interest will be creating a pair of 311's, but that's down the road).

One advantage to creating the CAD files ourselves would be that "we" would own the digital data that is used by the numerical cutter and could recoup the expenses over time.

Just my $.02, but I am more than willing to help because others have been so willing to help me. Just a small way of saying thanks!

Igor, can you tell me what form of cnc file he prefers to see for his cutter?

Ray Clark

[djnagle]

Ray, thanks for the offer. I am meeting with the guys next week sometime and will talk to them about programs.

[djnagle]

Bad news on the home front. I just got out of my meeting with the machine company. Dave (from here on the forum) lent me a 511 and after looking at the horn, Romeo Tech put the tab for digitizing, surfacing, and one pair of horns at around $3000.00, after that they could make the horns for $600.00 - 700.00 per horn. So even though I have had fun thinking about it, I can't aford to make it happen. After materials, a pair of horns would cost me $1700.00!!! To rich for my blood. Thanks to all for your input and ideas. Cheers.

[GM]

Can't say as I'm surprised, but now that we know for sure, let's look at a more realistic way to achieve the equivalent sonics. Virtually every manufactured or DIY horn has too small a mouth with little/no regard for mouth reflections back to the throat and the Altecs are no exception, so using your fave high density/stable hardwood, carve a two piece mouth extension (or have them do it) so that it fills in the entire area back to the flange. Mounting would be by compression, with wax paper as a 'gasket'. Then it's just a matter of making a box using the same (or similar, for contrast) wood back to the flange and filling it with Portland cement to get sufficient stiffness/damping.

High performance is in the details, so the finishing touchs would be to remove the small brace, cut the vane welds/add rubber inserts (or replace them with tapered hardwood versions), grind down the side wall welds/smooth/seal all surfaces, blend in the joint between the conical/expo expansion, lap surface the flange/compression driver mating surfaces, and align bore their throats using either tin foil or wax paper for the gasket.

No 'free lunches' though, the downside is it won't sound like a 511 any more than one carved out of a chunk of wood.

GM

[djnagle]

GM, just for clarification on the extention, are you saying to extend the lips of the top and bottom flares (following the contour established by the lips) out to the height of the mound flange? So the horn flare would be the same height as the mount flange?

[GM]

No, you want to roll the lips on over so that the WL launches off the mouth with no resistance or allow standing waves to develop, ditto the side walls. This will make the mouth somewhat larger than the flange. Look at the Pavillion 160: http://perso.club-internet.fr/ndavid.../exemples.html You want to make ~the equivalent termination.

Here's the info for plotting the side wall ones, then just blend the vertical ones to suit since they just need to have theirs completed.

http://perso.club-internet.fr/ndavid...htm#ancre68820

GM