Off on a tangent thinking - what would be the result if we turned a Cornu spiral on its head and reversed the horn into a tapered Transmission line. Use .50 Qts or higher speaker, make the center 2 to 4 times speaker's SD and maybe with the two different length channels, one of the channels will offset the 1st harmonic? Probably not a good idea since I haven't seen this mentioned anywhere.
This was covered as one of the alternate embodiments in the Cornu patent and also shown in their website. It would work to give tight bass but less gain. I haven’t modeled it yet.
You know, I think I will - The outcome should be interesting. I will use XRK's favorite speaker, Vifa TC9FD18-08 3-1/2 just so we can have a reference with the Cornu (and other enclosures.) Can I have some help with the starting parameters?
1. I have dollar tree foamcore as well as 24" x 24" 3/16 PVC sheets - Which one should I use for better sound? I'm not worried about the ease of use.
2. I will sketch the template and publish it for your advice but I need some info on these things:
a. Should I place the driver in the middle and see if we can decrease the harmonics by using two different channel lengths (if so, what should the difference in line lengths be? We can also vary the stuffing but it would be nice and lower bass if we can use the 2nd channel to help eliminate the harmonics.
b Or, should we do (a) as well as try to offset the driver in a different part of the "Cornu" spiral 1/3 the way from the center?
c What should the starting volume of the area around this driver be and what is the minimum depth behind the magnet including using 1/2" of felt behind the magnet.
d Of the two channel lengths, what should be our starting longest length line?
e I can't seem to find the patent number that XRK mentioned - Does anyone know how to view it?
Thanks
1. I have dollar tree foamcore as well as 24" x 24" 3/16 PVC sheets - Which one should I use for better sound? I'm not worried about the ease of use.
2. I will sketch the template and publish it for your advice but I need some info on these things:
a. Should I place the driver in the middle and see if we can decrease the harmonics by using two different channel lengths (if so, what should the difference in line lengths be? We can also vary the stuffing but it would be nice and lower bass if we can use the 2nd channel to help eliminate the harmonics.
b Or, should we do (a) as well as try to offset the driver in a different part of the "Cornu" spiral 1/3 the way from the center?
c What should the starting volume of the area around this driver be and what is the minimum depth behind the magnet including using 1/2" of felt behind the magnet.
d Of the two channel lengths, what should be our starting longest length line?
e I can't seem to find the patent number that XRK mentioned - Does anyone know how to view it?
Thanks
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Those look phenomenol Cal. Where do you plan to mount them? I've only picked up the last few pages, what is the driver u are using and is it contained in the box or is there a bump?
I built a pair of 16" Cornus last year with 2.5" Dayton drivers for my TV; every time I turn them on it makes me smile they're so bassy.
I built a pair of 16" Cornus last year with 2.5" Dayton drivers for my TV; every time I turn them on it makes me smile they're so bassy.
Yeah, that is what I was worried about - Since I haven't seen anything like this, I was questioning my "tangent" idea. However, I thought there might be some reasoning in this idea since the Cornu has two different lengths starting with two small channels expanding into a horns (small to large channel.) So why would it not work in reverse with two large starting channels going to tapered small channels, ie, T-Line.
Unless someone gives me some encouragement that it might work and help with the starting info that I outlined above, I will continue with my portable DOT video project. I just finished my 7 speaker, computerized DOT video artwork wall system. I like to have two projects going at the same time or I get bored.
thanks
Unless someone gives me some encouragement that it might work and help with the starting info that I outlined above, I will continue with my portable DOT video project. I just finished my 7 speaker, computerized DOT video artwork wall system. I like to have two projects going at the same time or I get bored.
thanks
You're right Fred, it's a 'controlled nutiness'
My wife has other words for it but I can't use those here on this family oriented site.
Thank you.
In the storage area with all the rest. No kidding, as a speakerholic, this just feeds an addiction.
TB W6-1139 woofer. Tang Band W6-1139SI 6-1/2" Subwoofer
These will give me the giggles too. I just hope they don't give me the ****s part. Every time I step up in size, they continue to amaze. I am expecting no less this time.
Here's the 20's, 27's, and 36's along with a drunken concoction I call the Penthorns
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Well, this is a Cornu thread. To reverse it makes it a whole new speaker. Nautilus comes to mind.
I encourage you to do it. I also encourage you to start a new thread so we can see the progress as we do here in the Cornu thread. Working with foam core is fun. Seriously. I don't mind the accidental blisters at all. Yes, it happens, don't kid yourself.
Happens mostly when my wallet does the talkin'
See above. I don't think we're alone here Fred.
Thanks for addressing all my questions Cal. And for the pics. Mmmm. Pictures. I get the speakerholic bug from time to time. Luckily don't have it at present. Too cold to think or feel anything this winter :0 In fact I've had the parts for dual TC9 0.53X Karlsonators sitting here for months. Finally a coupla weeks ago I cut out all the foamcore pieces. Now at least they're in a neat stack. But of course I have a few glorious foamy boxes to listen to already, so no rush. When the fever hits again I may take on a 27 or 36 Cornu. I can imagine that the sound out of those things is somewhat beefy. Thanks for the inspiration.
I wish strokes of genius would interrupt my thought process more often. While I'm lying in bed this morning, trying not to disturb the Mrs., it hit me. If you want to lay 46 ft. of glue on the edge of the foam before it skins over, you either need four people with a bottle of glue or you do something like this. It's just a paperclip taped to the nozzle. Hockey tape of course.
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