Ever think of building a Cornu Spiral horn? Now you can!

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So those ns3's are a winner in the cornu I take it?

Don't know the Visaton's.

Yes, Giau has been having fun with his friends. They keep looking for where the 'other' speakers are. Even his wife came downstairs to find out what all the racket was.

Remember, these are the more expensive NS3-193's not the NS3-194's. Much different driver.
 
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Don't know the Visaton's.

Yes, Giau has been having fun with his friends. They keep looking for where the 'other' speakers are. Even his wife came downstairs to find out what all the racket was.

Remember, these are the more expensive NS3-193's not the NS3-194's. Much different driver.

You mean his friends can't believe that such a big sound comes from those tiny drivers? Did you try those drivers in your cornu before sending them? How do they sound bass-wise and the balance with highs?
 
Sorry for the basic question: Would it be possible to do a Cornu-Spiral as a small sub with a shallow woofer, like the 5" Visaton? Or, since most of those waves are omni-directional, there is no need for a spiral horn, and a regular vented box (36" w x 36" l x 2.5" d = approx. 1.06 cu.ft. = 39 Hz) will do fine? Just to help the fill the lows that the full range spirals might not reach.
 
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I think Cal stuck a big coil on his FF125WK 28 in Cornucopya and turned it into a sub to use with his 20 in Cornucopya as the full range. It's back in this thread somewhere. I recall it worked quite well. Certainly a BR sub box is easy to build and will get you to 40 Hz, but the advantage of the Cornucopya is the fact that the sound emanates in 360 deg along a wall for bass enhancement and room filling presence, and there is less group delay than with a bass reflex. So the timing of the deeper bass notes doesn't feel delayed.
 
You mean his friends can'y believe that such a big sound comes from those tiny drivers? Dd you try those drivers in your cornu before dending them? How do they sound bass-wise and the balance with highs?
Yes, yes and they were just fine for $25 a pair. No need for augmentation on either end.
Sorry for the basic question: Would it be possible to do a Cornu-Spiral as a small sub
<snip> and a regular vented box
No, the Cornu is not intended as a sub, it would have to be very large and you quickly lose the appeal.
Regular box is better I think.
I think Cal stuck a big coil on his FF125WK 28 in Cornucopya and turned it into a sub to use with his 20 in Cornucopya as the full range. It's back in this thread somewhere.
I actually did that with the CSS VWR 126 with a coil in the 27" box and the LG 3" with a cap in the 20" I did it to get as much out of the system as I could. I pushed it 'prit' near the limit that night and had a blast doing it. Well into party SPL. Surprisingly balanced sound.

Creative Sound - Product Details
 
I think Cal stuck a big coil on his FF125WK 28 in Cornucopya and turned it into a sub to use with his 20 in Cornucopya as the full range. It's back in this thread somewhere. I recall it worked quite well. Certainly a BR sub box is easy to build and will get you to 40 Hz, but the advantage of the Cornucopya is the fact that the sound emanates in 360 deg along a wall for bass enhancement and room filling presence, and there is less group delay than with a bass reflex. So the timing of the deeper bass notes doesn't feel delayed.

Thanks!
 
Off Center Cornu on test

So I had finished my Cornus a week ago, but was disappointed on first listening. There was just no good low end to speak of, so I packed them away in the basement and did not speak.
Over the last weekend I had regrets on just burying the Cornus in the basement. Pulled them out again and run a frequency test using the amp with single ended 50 triodes this time. Seemed marginally better in the low end. So I run the Cornus for a few hours at "party level" like when you have to shout to have a conversation. Room modes were strongly excited. and after a while the SL12 RCA drivers seemed to nimble up and fill in down there. And sure enough in frequency tests now I began hearing at 20Hz, low level but there and it was much stronger at 80 and 100Hz with 125Hz not so pronounced stronger than 100Hz any more. Music was much more satisfying than on day one.
(to understand this, the SL12 is an alnico driver now well 60 years old with a surround less paper cone, just a folded paper section at the circumference. The paper is stiff, but very thin and obviously needs loosening in the circumference to come to greater voice coil excursions. Above all shortcomings a very good sounding extended range driver)

Lang Lang's piano on the Beethoven CD was way more exciting and so are all other instruments of the full orchestra.
In fact it is so amazing, you have to hear it. Even so they are on the wall the SL12 seem to be suspended free, there is nothing of an in the box sound and everything is free coming out but very controlled with very fast low end and no mush at full orchestra crescendo.
Cornu is doing the job and well. No stuffing or stiffening rods at all, although I might add that soon.
For more pictures see my gallery:
yet.electro aucoustic - My Photo Gallery
Guys I am still flabbergasted and surprised and happy.
There is a lot to be heard and learned from the basic Cornu design and alterations. Thanks to all on this thread and the great foam board idea!!!
 

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Glowglass,
Wow! What a cool set of speakers! Those are beeeg! You are now the envy of all Cornu owners. :) That must have been disheartening to go through what you did after your first listen. I am glad that you gave them another shot. Here is a real case of break-in (or should I say, re-breaking-in) being so important. Congratulations on a fantastic job. I wish i can hear it. Do you have videos or sound clips posted somewhere?
:cheers: