DIY Folded-Horn Speaker Design from 1955

I can, if there is a desire, make layouts of all the parts for the speaker box as I possess CAD software and work with design.
 
I've been struggling with libreCAD tonight, I left my AutoCAD license at work. Got it more or less drafted but the plans are definitely flawed. And libreCAD is pretty ugly compared to AutoCAD.

As is, the dimensions and angles don't quite add up. I will give it a few tweaks tomorrow to make it constructable, I'm really happy I'm drafting it, both because it's interesting to draft something, and because the plans as published need work.

Definitely have new respect for drafters, there's some wonderful ones at work, but sadly no charge code for popular mechanics speakers from 60 years ago.
 
I was bored so I did it anyway. I can if so wish add volume of the enclosure too as it is easy to pull out from my CAD.
 

Attachments

  • Folded Horn Assembly Standard 11x17.pdf
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  • Folded Horn Parts Standard 11x17.pdf
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  • Folded Horn Parts Metric 11x17 .pdf
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  • Folded Horn Assembly Metric 11x17 .pdf
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I can, if there is a desire, make layouts of all the parts for the speaker box as I possess CAD software and work with design.

If you're a professional designer, this should be a piece of cake. I think your work would be far and away better than what I've come up with, but I've got a 2D scale drawing about 80% done.
 
How about volume? Does it go from where speaker is mounted to edge of enclosure where it meets free air?

In the horn enclosure, volume isn't strictly important, but yes more or less like that but minus the volume of the speaker itself. In this case the volume of the speaker can be neglected.
 
2424.876 in^3 and then minus the volume of chosen speaker. White represents the volume in the picture and green is the speaker itself.
 

Attachments

  • Folded horn volume.jpg
    Folded horn volume.jpg
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2424.876 in^3 and then minus the volume of chosen speaker.

I'm happy you modified the design very similarly to how I did, changing the angles instead of the dimensions. Saves me lots of work, I draft extremely slowly and inefficiently.
 
The file format isn't supported on my phone's browser, can't open the files.
 
I spent my computer, cable modem, and other associated fees on new blades and tools. Can't see the benefit of paying double bills.
 
I spent my computer, cable modem, and other associated fees on new blades and tools. Can't see the benefit of paying double bills.

That's sensible! I still have a home phone, and cable tv I never watch. Way too much duplication.
 
I was bored so I did it anyway. I can if so wish add volume of the enclosure too as it is easy to pull out from my CAD.

HI,

Per the original plans the back panel and bottom should be 5" wide and not 5.5, they are inside the side panels. Can you check the drawings to make sure it doesn't affect any angles or measurements? That measured drawing is extremely useful, I just want to make sure it's accurate.

Note that the 5.5 measurement for the top also assumes that the side panels are 1/4" thick. The top and bottom aren't identical in the original plans, the bottom being 5" wide and the top 5.5.

Finally, since the top is the last item to be installed, I think the bottom would be a more suitable reference point for Y coordinate dimensions. This because during construction, the top will not be installed yet.

You've already done tons of work for a project which isn't yours though - the 3D model view is really cool. What CAD package are you using?

I'm much better at checking drawing than making them, you can guess what I do for a living.

Best regards

Max
 
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You're correct. I missed that in the process when making the solids. I make them oversized and then "cut" them down. I guess I should have done an interference check and that would have caught that. I will correct and update. Thanks for pointing that out.
 
HI,

Per the original plans the back panel and bottom should be 5" wide and not 5.5, they are inside the side panels. Can you check the drawings to make sure it doesn't affect any angles or measurements? That measured drawing is extremely useful, I just want to make sure it's accurate.

Note that the 5.5 measurement for the top also assumes that the side panels are 1/4" thick. The top and bottom aren't identical in the original plans, the bottom being 5" wide and the top 5.5.

Finally, since the top is the last item to be installed, I think the bottom would be a more suitable reference point for Y coordinate dimensions. This because during construction, the top will not be installed yet.

You've already done tons of work for a project which isn't yours though - the 3D model view is really cool. What CAD package are you using?

I'm much better at checking drawing than making them, you can guess what I do for a living.

Best regards

Max

I updated the drawings now, and checked for any interference and it passed, which is something I should have done before releasing them LOL. I can change, if so desired, the top and bottom to sit in between the side sheets instead of over them as the original plans call for. Actually, checking it now, they show it with top overlapping and bottom in between. It is just matter of preference I think and I simplified it a bit with two identical parts, but I might as well correct that too.

I am using KeyCreator by Kubotek. It is pretty simple once one gets the hang of it. I had a laptop dropped in my lap a few years ago with "here you go... I need this, this, and this." I just had to figure it out and that fast. The hardest part was figuring out how to get animations to work and to estimate dimensions from pictures as I have to do a lot drawings and animations for courts relating to all the forensics my boss does too.
 
Here's the one I did... note the amateur text sizes and dimensions :)
My concern is yours looks different from mine.
 

Attachments

  • SPEAKER .pdf
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here it is with more dimensions.

I based the difference between the tops and bottoms on the dimensions, and also the illustration of the bottom of the speaker with the foot on it.
 

Attachments

  • SPEAKER 2.pdf
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I updated the drawings now, and checked for any interference and it passed, which is something I should have done before releasing them LOL. I can change, if so desired, the top and bottom to sit in between the side sheets instead of over them as the original plans call for. Actually, checking it now, they show it with top overlapping and bottom in between. It is just matter of preference I think and I simplified it a bit with two identical parts, but I might as well correct that too.

I am using KeyCreator by Kubotek. It is pretty simple once one gets the hang of it. I had a laptop dropped in my lap a few years ago with "here you go... I need this, this, and this." I just had to figure it out and that fast. The hardest part was figuring out how to get animations to work and to estimate dimensions from pictures as I have to do a lot drawings and animations for courts relating to all the forensics my boss does too.

I've never tried that before. I started mine in horrible LibreCAD, and finished it in AutoCAD, which is definitely way better to use The reason I am sticking with the top and bottom being different, is I already had all the square pieces cut out and started on the angles, before I realized the issues with the original drawing. I had to take a step back, when nothing was fitting but the parts were cut right!
 
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