Lab 12 Based Offset Driver - Mass Loaded - Transmission Line (OD-ML-TL) Design by Bj - Page 18 - diyAudio
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Old 13th May 2013, 07:40 PM   #171
DrDyna is offline DrDyna  United States
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Quote:
Originally Posted by NWCgrad View Post
Here are my initial efforts for developing an enclosure for the model provided by tb46 (see attachment). I think the unfolded is pretty accurate, but somehow my calculated volumes did not perfectly match the Hornresp data from which the parameters were taken. Error is probably because I converted to Imperial measurements instead of working in metric.
Are the volumes too high? It might be the fold right at the bottom, you'd probably have to manipulate that last turn (bottom back) to keep the taper even.

Edit: Something like meow.
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File Type: jpg tb46 Hornresp Design.jpg (280.5 KB, 216 views)

Last edited by DrDyna; 13th May 2013 at 07:44 PM.
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Old 14th May 2013, 04:21 AM   #172
NWCgrad is offline NWCgrad  United States
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Yes, with folding I gained to much volume. Its a tall bugger at 102" but with proper folding it should be quite manageable. All I can say is folding is hard (at least for me).

I haven't modeled the Epic 12s in the enclosure, but I bet they add another 3 to 5 dBs.
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Old 14th May 2013, 04:34 AM   #173
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Why not do a standard TH style single fold and have a rear exit for corner loading?
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Old 14th May 2013, 04:38 AM   #174
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I think that will be to tall for my needs (however, if I buy an acoustically transparent screen and build a false front wall the options open considerably).
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Old 14th May 2013, 04:42 AM   #175
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Single fold = 51". Double fold = 25.5".
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Old 14th May 2013, 09:58 AM   #176
NWCgrad is offline NWCgrad  United States
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Single fold = 51". Double fold = 25.5".
I'm not smart enough to figure out a single fold, let alone double fold.

Attached is my latest stab (only took about 6 hours).

I have the L12 and L23 lengths correct, not positive about the volume. However, I can not figure out how to make the L23 fold twice to reach the front of the enclosure (based on Oliver's drawing from the link of page 14).

Hopefully one of the pros will jump in and assist with the folding.
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Old 14th May 2013, 10:02 AM   #177
NWCgrad is offline NWCgrad  United States
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Originally Posted by DrDyna View Post
Are the volumes too high? It might be the fold right at the bottom, you'd probably have to manipulate that last turn (bottom back) to keep the taper even.

Edit: Something like meow.
Aaargh, spent way to long today on this and still cannot get it how I want it. It's driving me nuts (well nuttier, my wife already thinks I'm nuts).
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Old 14th May 2013, 11:57 AM   #178
DrDyna is offline DrDyna  United States
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Aaargh, spent way to long today on this and still cannot get it how I want it. It's driving me nuts (well nuttier, my wife already thinks I'm nuts).
Hah, yeah, I tried to fold one once, I'm sure there's some tricks to it that once you learn make it easier.

One of these days, maybe Oliver will make a youtube video in fast-motion of how he does it with AutoCAD
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Old 14th May 2013, 12:07 PM   #179
NWCgrad is offline NWCgrad  United States
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I use (or more correctly try to use) PowerPoint and Paint. Not the best tools for the job! It does seem to be a black art.
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Old 14th May 2013, 01:27 PM   #180
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Hi Y'all,

I had actually started on this one, but have not found the time to finish it. Hopefully, by "manjana".... :-).

Regards,
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