I would be really interested in helping to develop this idea. There is currently a member on DIY audio who is offering CNC milling at great rates: http://www.diyaudio.com/forums/showthread.php?s=&threadid=131337
Perhaps we might even get a group buy together of the front and back baffles and then glue the inner ourselves from some ripped 1/8" ply
Perhaps we might even get a group buy together of the front and back baffles and then glue the inner ourselves from some ripped 1/8" ply
Here is the link to a Cornu build which offers dimensions:
http://sebastian-pitkanen.blogspot.com/2006/07/cornu-spiral-copy-horn.html
I cant vouch for the dimensions so it might be worth contacting the builder
http://sebastian-pitkanen.blogspot.com/2006/07/cornu-spiral-copy-horn.html
I cant vouch for the dimensions so it might be worth contacting the builder
Attachments
they are Sebastian's version.
This is a fabrication of the original cornu and some hints on construction from the designer:
Ivo has built spirals that way.
Compute the horn contour for 40 Hz exponential, assume a "height" of 15cm. Start at width 5cm. End at a width of around 1m.
Take a thin rope (cord?) and a large sheet of paper. Draw the horn contour (straight!) on the paper. Cut the "horn" out. Cut the "horn" into thin stripes and glue them to the rope so you can bend the "horn".
Take a plywood base plate of appropriate size and bend your horn on it. Mark the walls.
Now everything depends on your woodworking skills - it is quite difficult to put the spiral together...
This should help you to get started.
I recommend to use the Lowther DX4 and a rear chamber of about 30cm diameter. For those having a tight budget, the MONCAOR SP50X will do a fine job.
Perhaps we could take a shot at reverse engineering it from this info
This is a fabrication of the original cornu and some hints on construction from the designer:
Ivo has built spirals that way.
Compute the horn contour for 40 Hz exponential, assume a "height" of 15cm. Start at width 5cm. End at a width of around 1m.
Take a thin rope (cord?) and a large sheet of paper. Draw the horn contour (straight!) on the paper. Cut the "horn" out. Cut the "horn" into thin stripes and glue them to the rope so you can bend the "horn".
Take a plywood base plate of appropriate size and bend your horn on it. Mark the walls.
Now everything depends on your woodworking skills - it is quite difficult to put the spiral together...
This should help you to get started.
I recommend to use the Lowther DX4 and a rear chamber of about 30cm diameter. For those having a tight budget, the MONCAOR SP50X will do a fine job.
Perhaps we could take a shot at reverse engineering it from this info
Attachments
Hi guys - I hope not to take his off-topic but can anyone tell me please, why the difference between the two designs of spiral horn. One (the original version I believe), has 4 spirals, whilst the later model has a centre plate and 8 spirals - albeit those 8 are half the depth of the 4. Was this to 'ease' construction, or was it a fundamental update to improve upon the sound qualities?
I am considering taking up the router and undecided which version . . . . . !
cambshiregordon
I am considering taking up the router and undecided which version . . . . . !
cambshiregordon
- Status
- This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.