GM-416-8B MLTL Corner Cabinet

**VINTAGE52** · November 4th, 2016, 03:41 PM

Originally Posted by VolvoHeretic

Does anyone have a 811 exposed that they could measure for me? I know the flange width and height and also the overall length, but I need to know the height of the horn mouth and its width in front of the flange. I have a 511 and tried to scale it down, but I don't trust the dimensions.

Measured on the front of the flange; 16" wide, 7" high, 3-1/4" out. Don't forget the < > on either side where the halves are joined 1/8"-3/16" on each side.

**VolvoHeretic** · November 4th, 2016, 05:10 PM

Thanks guys, I used the link GM posted and I will put a note on the plans to verify ALL dimensions.

I can't post the new updated diagrams on Photobucket (at least it now let's me log in), because the website is down for maintenance and I have exceeded my quota on HostBoard. Altec Best, I can't imagine trying to manage two photo sharing accounts.

By the way, does anybody know if the horn shape is a simple arc or is it part of an ellipse (parabolic)?

GM · November 4th, 2016, 07:37 PM

The initial expansion is a conical round to rectangular transition to cover most of its BW, then an expo flare AFAIK [haven't reverse engineered it] to cover the low end, overall pattern control.

GM

**VolvoHeretic** · November 4th, 2016, 08:27 PM

Originally Posted by GM

The initial expansion is a conical round to rectangular transition to cover most of its BW, then an expo flare AFAIK [haven't reverse engineered it] to cover the low end, overall pattern control.

GM

Thanks GM, so I can assume that it is one quarter of a truncated ellipse (math is not my friend)(AutoCAD will only draw Arcs and Ellipses).

That bulge just in front of the 90 degree flare is interesting. I should take my 511 outside and take zoomed in pictures of its front, plan, and side views, import them, scale them. and draw 99% accurate drawings just for giggles. I could always use the digital calipers from work and make poster board cutout templates of the interior horn flares and make manufacturing drawings, except nobody likes these horns.

I would show my Volvo front suspension drawing from photos, except that Photobucket is OFF LINE!

James, the Heretic

**Phil-G** · November 4th, 2016, 09:31 PM

there's a lot to said for paper and graphite.

or even a ball point pen and an envelope

**VolvoHeretic** · November 4th, 2016, 09:51 PM

Originally Posted by Phil-G

there's a lot to said for paper and graphite.

or even a ball point pen and an envelope

Or bar napkin and beer.

**Phil-G** · November 4th, 2016, 10:18 PM

Originally Posted by VolvoHeretic

Or bar napkin and beer.

don't you mean bar napkin and lipstick?

**VolvoHeretic** · November 5th, 2016, 10:51 PM

My latest version of the front baffle.

My idea of using flat rings of brass for the bass speaker and the 5"-9" dia. adjustable port grill cloth frames hit a snag. I have figured out that you could cut both rings out of the same piece of flat plate so you would need two for both speaker. A quick search found a place selling 24"x24"x1/8" 260 brass sheets, except the price is $400, so $800 total.

They also sell 2'x2'x3/16 3003 aluminum for $30, I suppose it could be painted with a bronze finish.

**srivenkat** · November 6th, 2016, 01:20 AM

Originally Posted by VolvoHeretic

My latest version of the front baffle.

My idea of using flat rings of brass for the bass speaker and the 5"-9" dia. adjustable port grill cloth frames hit a snag. I have figured out that you could cut both rings out of the same piece of flat plate so you would need two for both speaker. A quick search found a place selling 24"x24"x1/8" 260 brass sheets, except the price is $400, so $800 total.

They also sell 2'x2'x3/16 3003 aluminum for $30, I suppose it could be painted with a bronze finish.

VolvoHeretic,

Great diagram, thank you. Interesting thought on brass rings, or, I thought of using removable port boards.

Also, for the curved back, I spent more time today trying (smaller boards and logs) on the cuts to make the joints. It is getting simpler, I initially took that as semi-circle and counted the number of boards (# 8) but the 22.5 degree cut (on the edges) didn't align to get the depth (26-1/2) and width. So, each piece edge requires different angle cut to align for this measurement. Not sure whether the CAD diagram can suggest the required angle for each board on both edges.
Now, I am planning to cut different angle edges (15, 22.5, 30 and other sizes) to try to get the right shape. Once I figure out the right angles, things can get better.

Thank you,
Sri

**VolvoHeretic** · November 6th, 2016, 01:51 AM

Originally Posted by srivenkat

VolvoHeretic,

Great diagram, thank you. Interesting thought on brass rings, or, I thought of using removable port boards.

Also, for the curved back, I spent more time today trying (smaller boards and logs) on the cuts to make the joints. It is getting simpler, I initially took that as semi-circle and counted the number of boards (# 8) but the 22.5 degree cut (on the edges) didn't align to get the depth (26-1/2) and width. So, each piece edge requires different angle cut to align for this measurement. Not sure whether the CAD diagram can suggest the required angle for each board on both edges.
Now, I am planning to cut different angle edges (15, 22.5, 30 and other sizes) to try to get the right shape. Once I figure out the right angles, things can get better.

Thank you,
Sri

Sri, the boards are angled 30 deg. from one to the next, so the miter angle for each board edge is half of that or 15 deg.