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

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Yup, not only is the flange mount recessed but you'll note the magnet shielding is actually wider than the flange. That's a first for me. Those cost only 9 bucks for 4 of them.

Where are you getting them for 4 for $9? That sounds like too many units to be thrift store. We don't have Sally Ann in US. In fact, I had never heard of Sally Ann before and looked it up to see that it is owned by Salvation Army.

There is the Vifa tc6fd 2 in driver that looks like it will have to be mounted from inside for same reason.
 
Where are you getting them for 4 for $9?

The centre channel plus the left and rights from an incomplete set of Panasonic plastic speakers. $2.99 per piece, no tax. All I do is pick them up and if plastic speakers are heavy, I take a chance

The JVC's on the other hand came in a very nice, curved sided box with a flared port and a neat grill mounting system. Those were $20 for the pair. High priced by Sally Ann standars but they looked and felt good. So far they are real goodies. As mentioned the high end is good if on axis.
 
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Ahh... so the trick for shopping used cheap speakers is the weight. A sure sign of a big magnet. I will keep this in mind the next time I am at a thrift store or a garage sale. :)

Don't know if you have Ross stores in Canada, but they sell discount clothes, housewares, bedding, etc. They often have deals on computer speakers and other electronics in a grab bin near the front. I still kick myself for not grabbing the nice concave style 2 in aluminum drivers with rubber surrounds in nice housings when I was there last time. Amp and all for $10. Would have made a nice set of desktop Cornu's.
 
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Ross stores in Canada

Maybe not in Canada but an hour south of the border, once a year I take my honey to Bellis Fair Mall in Bellingham Wa. I drop her off, go to the 'something or other country buffet' and meet up with her later after I'm too full to be useful.
Are you telling me I should shop with her at Ross? You're really cramping something here X. :)
 
Finally Ready to Build

Finally moved, getting settled, cannot fight the urge anymore!
Been following every word on the thread, so my question is, Is there any experimentation that needs to take place with the chamber etc?

The driver I am starting with is a 2" Tymphany, specs:
Power handling: 10 watts RMS/20 watts max • VCdia: 13/16" • Le: 0.12 mH • Impedance: 8 ohms • Re: 7.1 ohms • Frequency response: 148-20,000 Hz • Fs: 148 Hz • SPL: 83.7 dB 1W/1m • Vas: 0.008 cu. ft. • Qms: 3.4 • Qes: 0.54 • Qts: 0.46 • Xmax: 1.45 mm • Dimensions: Overall diameter: 2-5/8", Cutout diameter: 2", Depth: 1-3/8".

Was thinking about a 14"-15" unit. Any ideas or thoughts that need testing? Ready to build and report back!
 
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Zayne,
Good to hear you are rearing to jump in to this! What is the Sd of the driver? A typical 2 in class driver will have Sd of about 15 cm^2. There is some experimentation regarding driver chamber volume vs throat area and how this affects the upper cutoff freq. I suggest you first make a standard plan cornu, then you can play with adding volume filler to the chamber. For the driver you are selecting, a 15 in may be a good idea x 2 in to 2.5 in deep depending on how big the Sd is. Either will work but it changes how much midrange comes out if horns. I have made a 14 x 2 in cornu for a 2 in Visaton FRS5 look alike driver and it works very well. I think the Tymphany has more Sd and certainly more xmax and lower Fs so a larger size may benefit, hence the 15 in.
Good luck!
 
Hi guys- I am thinking of making another pair of Cornus using a couple pieces of art that I have. They are 12" square. Given that parameter what size driver would be ideal. I'll be going thrift store shopping to try and find something suitable. Would a horn depth of 2" be right for this size?
By the way- I love the 2 sets I have already built- can't believe the sound :D:D:D

cheers
 
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Prezden,
Can you mount the art on a 14 in foam core board and use suitable framing or mattes to cover the 2 in border? The 14 in size is as small as I would want to go with a 2 in driver. For 1 in driver didn't you make thiose tiny closet speakers? A 1 in driver could be used in a 12 inch cornu. I would probably make it 2 in deep to get about 5 cm sq cm of throat area. The foam will take up significant channel throat width and I think throat gap will be about 0.2 in wide. Assuming this, the depth of channel needs to be about 2 in still.
Good luck on your search for used drivers.
 
I built a pair of these a couple weeks ago for my son's room. 20"^2 x 2"D - 2" drivers from a logitec speaker. I didn't put too much care into the build but they sound pretty good and look okay. Unstuffed they sounded terrible (!) but are great with a fistfull of wadding. Thanks for the idea guys!
 

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