Big Smith Horn

[Joe Alesi]

Hello All,

I hope everyone is happy and well.

I have an oppourtunity to get two 2309 horns from the 2390 Acoustic Lens/Horn almost for free.:applaud:

There are no lenses with these and I suppose I could do a simple DIY venetian thing, but I thought of something more extravagant like using it as a throat for a LARGE smith horn. The exit from the horn mouth is rectangular and about 6 x 9 inches.

What are your thoughts on using this as a throat in a 300/400 Hz Smith Horn for use with a 2440/1 now or 2482 someday? I would be using JBL 4560 cabinets (with 2226?) below these.

What are your thoughts?

Best
JA

[yggdrasil]

I don't think it would be a good idea. You will have some problems caused by the transition from the 2309 profile to the Smith profile.


If you want a big smith horn, just build it from the start. But beware that a smith horn capable of 300Hz will be gigantic.

Designed for 2490 (3" driver) it will be ~2m wide with JBL 2397 format or ~1.2m wide with the original Bob Smith format.

Designed for 2482 (2" driver) it will be respectively ~3m/1.8m wide.

You can increase the gap between the lips in order to make the horn smaller. This will be at the cost of vertical dispersion and probably HF response.

[Joe Alesi]

Hello yggdrasil,

Thanks for your reply. Yes the transition would be an issue if not smooth. I suppose I would just like to try a Smith horn and I saw these horns as a possible throat device. Maybe I could grow it into an Altec type Multicell instead!:bouncy:

Best
JA

[yggdrasil]

Multicell is a road I have not tried.

I have looked into radials though. You can look at http://audioheritage.org/vbulletin/showthread.php?t=15395 and http://audioheritage.org/vbulletin/showthread.php?t=8363

I have some more work to do on the spreadsheet. The resulting horns are beautyful both visually and sonically.

[Joe Alesi]

Wonderful work yggdrasil.

Thankyou for sharing your skill. I like the idea even for the prototype of using a belt sander. With your radial milling arrangement:applaud: :applaud: :applaud: I suppose you used some sort of round bottomed cutter- can you discuss this, size etc...

Best
JA

[yggdrasil]

The router bit was 1/2" wide, round.

This worked great towards the mouth of the horn. I will swap in a 3/4" flat bit for the flatter areas nearer the throat on my next project.

[Joe Alesi]

Hello All

I just had another idea regarding using the "free" 2309 horns (without lenses). I could do the JBL Paragon thing and fire the horn at a glancing angle into a curved reflective panel for better dispersion. I would be curious as to your opinions on this and also people's opinions of any Paragon systems or clones they may have heard, particulrly compared to say a 2350 which I am trying to get.

Thanks in advance for your thoughts.:)

Best
JA

[Hoerninger]

... I could do the JBL Paragon thing and fire the horn at a glancing angle into a curved reflective panel for better dispersion. I would be curious as to your opinions on this and also people's opinions of any Paragon systems or clones they may have heard, ...

You can try it yourself. Take a piece of cardboard 5 feet long with a apropriate height and bow it. Dimensions are not critical.

I've tried it this way with fullrange speakers (no horn). The stereo effect is all over the room even aside of the speakers. When staying in front of the speaker basis a stable imaging is given. (The basis of the Paragon is small.)

The reflector will distribute the sound round about +/- 45 degrees - not more although some have claimed it. A construction of sound directions as with light beams will give an insight.

The Paragon patent is attached.
___________
Peter

[Joe Alesi]

Hello Peter,

Thankyou for your insight- good idea re the cardboard trial. I will have a good read of the patent.

Best
JA