Thanks guys- I have to find someplace in Canada where I can the bluetooth modules- The shipping from parts express is more than double the cost of the modules. Mouser have these: How do I wire them up? 
SPBT2632C1A.AT2 STMicroelectronics | Mouser
SPBT2632C1A.AT2 STMicroelectronics | Mouser
Big Budget Cornu (BBC) that Packs a Punch!
OK, I have been messing around with modeling speakers way too long and not getting to do any actual building speakers. It's making me pretty antsy... I have what I think is a pretty cost effective design for a Big Budget Cornu (BBC) that packs a punch.
The idea is this, how can one build a speaker that can throw a decent 90+ dB (50 Hz to 100 Hz) bass shelf at least 3 meters away on 1 watt for as little $ as possible.
The design I have come up with uses the $3.60 Aurasound NS525 driver that has been successfully used in the DNA horn. The Madisound Speaker Store
Match that to a 36 in x 4 in deep Cornu spiral horn, fitted with a simple conical front horn that goes from 12.5 cm x 12.5 cm throat to 23 cm x 23 cm throat with a 10 cm depth.
I am thinking that the front and back panels can be made from two sheets of 4 ft x 8 ft x 1/8 in thick luaun plywood ($12 ea). The channels and front horn will require about 6 sheets of 30x20 in foam core ($6).
So we are at $15 for drivers (with shipping), $24 for plywood, $6 for foam core, maybe $5 hot melt sticks. Total cost is $50. But here is what you get:
First plot is frequency response at 3 m with 1 watt. Second plot is impedance. Third plot is cone displacement.
This is perfect for a low power tube amp, a 5 watt Nelson Pass single ended class A ACA, etc.
Any takers? This will probably be my next project once I get back in build mode.
Make no mistake, this is a BIG speaker with 9 square feet of baffle. But it mounts on a wall and is relatively thin. The sound will be BIG with little power driving it.
Have fun.
OK, I have been messing around with modeling speakers way too long and not getting to do any actual building speakers. It's making me pretty antsy... I have what I think is a pretty cost effective design for a Big Budget Cornu (BBC) that packs a punch.
The idea is this, how can one build a speaker that can throw a decent 90+ dB (50 Hz to 100 Hz) bass shelf at least 3 meters away on 1 watt for as little $ as possible.
The design I have come up with uses the $3.60 Aurasound NS525 driver that has been successfully used in the DNA horn. The Madisound Speaker Store
Match that to a 36 in x 4 in deep Cornu spiral horn, fitted with a simple conical front horn that goes from 12.5 cm x 12.5 cm throat to 23 cm x 23 cm throat with a 10 cm depth.
I am thinking that the front and back panels can be made from two sheets of 4 ft x 8 ft x 1/8 in thick luaun plywood ($12 ea). The channels and front horn will require about 6 sheets of 30x20 in foam core ($6).
So we are at $15 for drivers (with shipping), $24 for plywood, $6 for foam core, maybe $5 hot melt sticks. Total cost is $50. But here is what you get:
First plot is frequency response at 3 m with 1 watt. Second plot is impedance. Third plot is cone displacement.
This is perfect for a low power tube amp, a 5 watt Nelson Pass single ended class A ACA, etc.
Any takers? This will probably be my next project once I get back in build mode.
Make no mistake, this is a BIG speaker with 9 square feet of baffle. But it mounts on a wall and is relatively thin. The sound will be BIG with little power driving it.
Have fun.
Attachments
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Kiwi Cornu
I'm pretty late to the Cornu party, but then again only found this site a few weeks ago.
I have some AN Super 8's that I want to put into an enclosure but after having read about the Cornu's I thought I'd give those a go first.
This being my very first project, I thought I'd play it safe in order to avoid disappointment and go for a straight copycat of X's first one: 20" X 20" with the Vifa TC9FD18. So I got those ordered and had them shipped over here ($40 for shipping..., but have little options in that regard).
After they arrived I hooked up the Vifa's and let them break in for a while as my regular stereo speakers. The sound was pretty much what you could expect from just a little 3.5" driver sitting on the mantelpiece on their own: not much..
Anyway, I glued up one speaker last night and have mounted the driver tonight and started listening to it:
I'm very pleasantly surprised at the change: This speaker sounds very nice with very nice bass (to my untrained ears anyway). Quite amazing what this little thing can do once its in the enclosure!
Now on to glue and mount the second one and hopefully have them both going tomorrow night!
For the build I used foam core for the horn channels and 4.75mm MDF for the face and back, since the price of foam core and MDF is pretty much the same over here and I didn't want to buy more than 1 sheet of FC (32 x 40).
A stack of left over terracotta floor tiles came in very handy for clamping the speakers, as you can see from one the pics.
So, all up this has been a very rewarding first project with a good outcome.
Thanks xrk971 and all the other contributors.
Now thinking about a full size Karlsonator for my AN8's ...
Attached are a few pics of the build.
I'm pretty late to the Cornu party, but then again only found this site a few weeks ago.
I have some AN Super 8's that I want to put into an enclosure but after having read about the Cornu's I thought I'd give those a go first.
This being my very first project, I thought I'd play it safe in order to avoid disappointment and go for a straight copycat of X's first one: 20" X 20" with the Vifa TC9FD18. So I got those ordered and had them shipped over here ($40 for shipping...
, but have little options in that regard).After they arrived I hooked up the Vifa's and let them break in for a while as my regular stereo speakers. The sound was pretty much what you could expect from just a little 3.5" driver sitting on the mantelpiece on their own: not much..
Anyway, I glued up one speaker last night and have mounted the driver tonight and started listening to it:
I'm very pleasantly surprised at the change: This speaker sounds very nice with very nice bass (to my untrained ears anyway). Quite amazing what this little thing can do once its in the enclosure!
Now on to glue and mount the second one and hopefully have them both going tomorrow night!
For the build I used foam core for the horn channels and 4.75mm MDF for the face and back, since the price of foam core and MDF is pretty much the same over here and I didn't want to buy more than 1 sheet of FC (32 x 40).
A stack of left over terracotta floor tiles came in very handy for clamping the speakers, as you can see from one the pics.
So, all up this has been a very rewarding first project with a good outcome.
Thanks xrk971 and all the other contributors.
Now thinking about a full size Karlsonator for my AN8's ...
Attached are a few pics of the build.
Attachments
Peterv,
Wow! Congratulations on a great build! It looks like you built a copy of the very first Cornu I made based on the modified channel paths that I used with the squared angular internal passages in the first part. I am happy to hear that the sound is pleasing. It's a fun little speaker and a unique conversation piece when friends come over.
Looking forward to seeing what you do with the AN 8.
Regards,
X
Wow! Congratulations on a great build! It looks like you built a copy of the very first Cornu I made based on the modified channel paths that I used with the squared angular internal passages in the first part.
I am happy to hear that the sound is pleasing. It's a fun little speaker and a unique conversation piece when friends come over. Looking forward to seeing what you do with the AN 8.
Regards,
X
Very nicely done
Thanks prezden. All that I need to do now is finish them off with some cool art prints like the ones you have on yours!
I have build my FC Cornu a while ago and put i a side. Why? well i tried different kinds of glue to glue to glue the two parts together but again and again with the same results it lets go on the edges and leaked. So since you have a successful build which glue or kind of glue did you use? i am sure it is already been answered somewhere but could not find it.
Goeienavond.
I used Gorilla wood glue. It is polyurethane based and foams up around the edges hence sealing the gaps.
Hope that helps.
groeten
Peter V
Attachments
I use combo of pva and hot melt glue to cap off the top panel. Add hot melt to the inner channels where a leak would kill bass. You can't lay very much of it down before it hardens so do it in the first driver chamber then and maybe a few inches out. The rest use pva and a big clamp weight like books or barbells (or tiles in this case). I haven't tried Gorilla glue but hear it works very well.
I had a chance to hear a couple pairs of these at VI diyFest last week. Thanks Cal for sharing with us! Awesome amount of bass!
I'm planning on making a small pair with some cheep Aura 3-inchers.
From what I've read, the smaller scale cornu is easier to adapt different drivers (typical 3-inchers). Going larger takes a little more figuring (rear chamber, path lengths, and overall dimensions). With that in mind, the TB W8-1772 looks like maybe the ultimate driver for this kind of application, if the bass can be tamed. (somewhat pricey though )
http://www.parts-express.com/pdf/264-893s.pdf
I'm planning on making a small pair with some cheep Aura 3-inchers.
From what I've read, the smaller scale cornu is easier to adapt different drivers (typical 3-inchers). Going larger takes a little more figuring (rear chamber, path lengths, and overall dimensions). With that in mind, the TB W8-1772 looks like maybe the ultimate driver for this kind of application, if the bass can be tamed. (somewhat pricey though
)http://www.parts-express.com/pdf/264-893s.pdf
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Dave,
The 3 in Aura's as I recall work really well from what Cal and his BIL did. The TB 1772 is an 8 incher and that will be a HUGE Cornu - we are talking 15 to 17 square feet of baffle! You can make it smaller by designing your own custom channels, but if you simply scale the basic plan (which was designed for a 4.5 in driver) you will get a 50 inch x 50 inch or 17 square foot baffle Cornu! 48 in can probably work and that will fit exactly a front and back panel for a single sheet of plywood. Doesn't have to be thick plywood, probably 1/4 in is sufficient. Let me know if you are serious and I can run a sim with the venerable W8-1772 for you to fine tune the channel depth and throat openings.
Regards,
X
The 3 in Aura's as I recall work really well from what Cal and his BIL did. The TB 1772 is an 8 incher and that will be a HUGE Cornu - we are talking 15 to 17 square feet of baffle! You can make it smaller by designing your own custom channels, but if you simply scale the basic plan (which was designed for a 4.5 in driver) you will get a 50 inch x 50 inch or 17 square foot baffle Cornu! 48 in can probably work and that will fit exactly a front and back panel for a single sheet of plywood. Doesn't have to be thick plywood, probably 1/4 in is sufficient. Let me know if you are serious and I can run a sim with the venerable W8-1772 for you to fine tune the channel depth and throat openings.
Regards,
X
Thanks for the response.
I don't think I have room for a Cornu using the 8" driver. The room would probably need to be large as well. I was only referring to the W8-1772's frequency response which might be ideal for this kind of application (rising spl with increasing frequency). Maybe a smaller driver with a similar freq response would be more feasible/desirable.
I plan on using the little 3" (cheap) Auras. The back wall of my shop space has room for a pair that size.
I don't think I have room for a Cornu using the 8" driver. The room would probably need to be large as well. I was only referring to the W8-1772's frequency response which might be ideal for this kind of application (rising spl with increasing frequency). Maybe a smaller driver with a similar freq response would be more feasible/desirable.
I plan on using the little 3" (cheap) Auras. The back wall of my shop space has room for a pair that size.
Who had the W3-881's at diyFest with the white 166 woofers, was that Kyle? Those might be a good candidate too.
If it were me I would do a 20" or larger cabinet. Can you imagine what they might do to a 3" driver? The difference between the 20" and the 27" is phenomenal so what about a 23.75"? Makes sense from a cut perspective.
If it were me I would do a 20" or larger cabinet. Can you imagine what they might do to a 3" driver? The difference between the 20" and the 27" is phenomenal so what about a 23.75"? Makes sense from a cut perspective.
Cal,
I have been wanting to try a 24 in x 4 in Cornu for some time now. I think a W4-1337 bamboo driver maybe the way to go with this. I don't know if you have seen my sims for the "Big, (on a) Budget Cornu (BBC)" 36 in Cornu using the really inexpensive Aura NS525 (5.25 in) driver (http://www.diyaudio.com/forums/full-range/225622-ever-think-building-cornu-spiral-horn-now-you-can-97.html#post3558447) - coupled with a short front horn and a cheap tweeter, this thing can really have some potential.
X
I have been wanting to try a 24 in x 4 in Cornu for some time now. I think a W4-1337 bamboo driver maybe the way to go with this. I don't know if you have seen my sims for the "Big, (on a) Budget Cornu (BBC)" 36 in Cornu using the really inexpensive Aura NS525 (5.25 in) driver (http://www.diyaudio.com/forums/full-range/225622-ever-think-building-cornu-spiral-horn-now-you-can-97.html#post3558447) - coupled with a short front horn and a cheap tweeter, this thing can really have some potential.
X
