Probably very late to this thread but inspired by all of you I built myself a couple of quick cornucopas about half a year ago. After always having a pair of floorstanders powered by an Edison 60 I have wanted a less visible system, something less of a boy room, and the idea of having the speakers hanging on the wall powered by an amp that I could hide in a shelf was very interesting to me.
I bought a pair of speakers for wall mounting, not expensive but still a decent hifi-brand with good rep, but even after only half a day of listening I just had to return them. Such a compromise in sound was not something I was prepared to make and I thought the cause was lost.
This was until I found you guys! The prototypes are 50 by 50 cm built of 6 mm MDF that I cut halfway through in order to bend to shape as the foamcore is crazy expensive here in Scandinavia. The drivers are a pair of very old 2-3" Sonys from some compact stereo salvaged by my brother. Looking to what they are made from the sound is amazing, decent on high tones very good mid and looking to size of drivers the bottom is deep. I am now looking to build a pair of more permanent ones, full size 74 cm and buy new drivers.
This is where I would very much appreciate your input, the drivers I am looking at, based on price and availability, are Monacors SP-50X, SPH-60X or Faital Pro 4Fe35. Any input on any of these drivers and what depth should I be looking for in these real ones?
I bought a pair of speakers for wall mounting, not expensive but still a decent hifi-brand with good rep, but even after only half a day of listening I just had to return them. Such a compromise in sound was not something I was prepared to make and I thought the cause was lost.
This was until I found you guys! The prototypes are 50 by 50 cm built of 6 mm MDF that I cut halfway through in order to bend to shape as the foamcore is crazy expensive here in Scandinavia. The drivers are a pair of very old 2-3" Sonys from some compact stereo salvaged by my brother. Looking to what they are made from the sound is amazing, decent on high tones very good mid and looking to size of drivers the bottom is deep. I am now looking to build a pair of more permanent ones, full size 74 cm and buy new drivers.
This is where I would very much appreciate your input, the drivers I am looking at, based on price and availability, are Monacors SP-50X, SPH-60X or Faital Pro 4Fe35. Any input on any of these drivers and what depth should I be looking for in these real ones?
I've been trying to find how to measure the inner spiral "baffles." Is it done by transferring the scaled drawing (the one the 74cm X 74cm panel) to a sheet 74cm X 74cm? I have a pair of RS40-1354 drivers I'd like to use in something. I'm thinking of trying a cornu-spiral for them. I have the itch to build something, but it's pretty cold in the garage, so I'd like to find something I can do in the house; thus, the cornu-spiral. I'll use foam core for it, if I can figure out how to do the "spiral" aspect.
Thanks,
Mike
Thanks,
Mike
I just built mine to scale using the scale drawing found in the thread. I used underlayment (cheap 1/4" luan plywood) for the front and back. then I drew a scaled grid on the inside of the back and eyeballed the spiral patern from the drawing. I used hot glue to attach the spiral "fins" to the back and reinforced the joints with caulk when done gluing. I increased the size of the chamber in my build to help with the cutoff of HF. Did the driver cut out on the front first then used silicone caulk to attach the front to the fins, pretty strong joint. Need weights when gluing, I did mine on the garage floor with trash cans on top as weights. When done I needed to stuff the passages to taste with some dacron fill to get the best out of the sound. fun build and worth it. good luck.
Paul
Paul
Hey Mike. If you look back always, you'll see the 1354s in a 36" unit. I think it's too big a driver for the 27". On top of that, the wow factor is worth it. When I take them out in public, people's jaws drop. Well worth it.
Start at post 1544 and work your way through. The meat gets going around 1572.
Start at post 1544 and work your way through. The meat gets going around 1572.
Thanks Cal. Where do I find the layout for a 36" unit? My issue right now is figuring out the inner spiral baffles; how long and how to draw/lay-out the spirals on which the baffles lie.
I also have some NLA TangBand W3-879 drivers (3") I'm thinking might work.
However, I'm stuck on the inner baffles at the moment.
Thanks!
Thanks! A bit sloppy as this was only a prototype but they've convinced me! Nope, no extra attention was needed to bend the mdf to shape, I just had to be careful when bending the tight corners in order not to snap it. A bonus was that I got a reason to build a small table saw sled!
Two lessons learned though if anyone is looking to use this method: 1) use something round to bend around so not to snap the piece and 2) fill the sawn strips on the very outer corners so that it is possible to sand them down without breaking through the thin material. I did not do this on these ones but I will use a mix of wood glue and mdf-dust on my real ones.
Hi Cal,
I didn't post any, if he is interested he can look back through the thread to find the ones I had already posted on my build. I thought it was pretty simple to scale up actually, all you need is a ruler, straight edge, and pencil.
Paul
Thanks Cal. I had a chance to look through your posts using a 1354. Very interesting.
Mike
No input to any of these drivers? I know you guys have tried the lot and although I do like to experiment I feel you have already done this..
Hello xrk971,
I'm new on the forums. I'd like to ask your opinion on something:
I'd like to build a Cornu spiral horn, I've read much things but I'm not that much expert in electronics so... I have a room of about 50 square meters large. I'm listening to music 6 meters from the wall where are located the speakers. Would this Cornu Spiral Horn for my room or it would be better to build something else?
This is a picture taken from my listening place.
Thanks for the answer.
I'm new on the forums. I'd like to ask your opinion on something:
I'd like to build a Cornu spiral horn, I've read much things but I'm not that much expert in electronics so... I have a room of about 50 square meters large. I'm listening to music 6 meters from the wall where are located the speakers. Would this Cornu Spiral Horn for my room or it would be better to build something else?
This is a picture taken from my listening place.
Thanks for the answer.
Nerone,
You have a nice space there. 6m is quite far to be from a speaker to listen to it - what type of music do you enjoy, how loud do you like to listen, and are you aiming for a wide sweet spot or really nice imaging at one smaller sweet spot? How important is wide dynamic range and impact? How much do you want to spend?
There are some choices for speakers farther way from the back wall - floor standing or stand mounts. They offer better imaging. You could go with a bookshelf or stand mount 2 way FAST (low XO at circa 500Hz).
Cornu is more for casual listening or background music. For wide sweet spot look at Karlsonator or XKi.
For best dynamic range and imaging, go with a Trynergy horn. That should not be your first project though.
There is also the open baffle top and sealed or reflex bass in a FAST.
Tell me how you listen and what you listen to and I can give better recommendations more focused for your needs.
You have a nice space there. 6m is quite far to be from a speaker to listen to it - what type of music do you enjoy, how loud do you like to listen, and are you aiming for a wide sweet spot or really nice imaging at one smaller sweet spot? How important is wide dynamic range and impact? How much do you want to spend?
There are some choices for speakers farther way from the back wall - floor standing or stand mounts. They offer better imaging. You could go with a bookshelf or stand mount 2 way FAST (low XO at circa 500Hz).
Cornu is more for casual listening or background music. For wide sweet spot look at Karlsonator or XKi.
For best dynamic range and imaging, go with a Trynergy horn. That should not be your first project though.
There is also the open baffle top and sealed or reflex bass in a FAST.
Tell me how you listen and what you listen to and I can give better recommendations more focused for your needs.
xrk971.
Hello, thank you for your answer. The genre of music I listen to are including classic pop and rock. Groups like Dire Straits and Pink Floyd and sometimes even a bit of jazz and blues. I don't listen to classical and metal music.
Usually, I listen to music at an average volume even though sometimes I don't mind to turn the volume up and enjoy the powerful bass. Unfortunately, I live in a flat and I have to follow the rules and keep quiet most of times. For the construction of the deflector I'm fine because I could build it right away but I like your design made in feathered cardboard and their designer. I was thinking of building this corn spiral horn because they looked pretty cheap and I was hoping to spend over 100 hundred bucks, but only if with it I could enjoy a sweet and fatigue-free listening. Currently, I'm using the TPA 3116 D2 and a modified preamplifier guanzo 6n3 tda7297 and a modified Fenice 20 (ta 2024) using the chromecast audio. I'm also waiting for 2 TDA8932 and tpa3118 mono you're recommended others in your thread. Greetings
Hello, thank you for your answer. The genre of music I listen to are including classic pop and rock. Groups like Dire Straits and Pink Floyd and sometimes even a bit of jazz and blues. I don't listen to classical and metal music.
Usually, I listen to music at an average volume even though sometimes I don't mind to turn the volume up and enjoy the powerful bass. Unfortunately, I live in a flat and I have to follow the rules and keep quiet most of times. For the construction of the deflector I'm fine because I could build it right away but I like your design made in feathered cardboard and their designer. I was thinking of building this corn spiral horn because they looked pretty cheap and I was hoping to spend over 100 hundred bucks, but only if with it I could enjoy a sweet and fatigue-free listening. Currently, I'm using the TPA 3116 D2 and a modified preamplifier guanzo 6n3 tda7297 and a modified Fenice 20 (ta 2024) using the chromecast audio. I'm also waiting for 2 TDA8932 and tpa3118 mono you're recommended others in your thread. Greetings
I have moved the latest posts over to the foam core thread so we can concentrate on Spirals here.http://www.diyaudio.com/forums/full-range/223313-foam-core-board-speaker-enclosures.html