Reverse horn cabs

[hayseed]

I was wondering what benefits/ negatives surround reverse horn cabinets? I have only seen them used for PA  purposes but if i am not mistaken, the reverse horn design can also be used for bass guitar cabs. I am looking a Sunn 215S with a reverse horn. My Sunn cab (215) has the speakers facing front. Would this sound ok together or too "bassy" and muffled?

[Hemisaurus]

Benefits

• They sound awesome
• You get more sound for your watt
• Horns are the only loudspeaker cabinet design, that allow a loudspeaker to produce frequencies below the resonant frequency of that loudspeaker driver
• Horns get more efficient the more surfaces they touch, put one on the floor, the effective mouth area has doubled, push it against the wall too, it's quadrupled, improving bass response
• Horns couple with each other, put two horns together, they now are one horn with twice the mouth area (and better bass response)

Drawbacks

• Size-wise they are generally bloody huge
• Slow response time, they are not punchy

Horns are awesome, that's all I have to say. A rear loaded horn (not reverse) is one where the rear of the driver is chambered into a horn, and the front of the driver is left facing the world, this was to give a best of both worlds situation where the bass is handled by the horn, and the driver does the higher frequencies.

In practice there is a point where the two interfere with each other, and this will result in a dip at a particular frequency, in a traditional 18" horn that's maybe somewhere in the 70-90Hz range, 15's it's slightly higher.In PA's you combat this with a crossover, and run the horn below this drop-off point, playing a bass through them, it's generally not noticeable.

The Sunn cab is more of a short horn, it's almost too small to be a horn, more of a large port, so it sort of hovers between being a bandpass and a horn cab. They do sound good, I have a Peavey of the same design with a Sunn bass transducer on top and a Eminence 300W below (Gamma or Delta maybe) and it kills.



The two cabs on the right are tradition scoop rear loaded folded horns, and sound great, my favourite is the EV cab the cat sits on, not really rear loaded as they reversed the driver so they could get more chamber area, this is the cab that with only 50W from my old receiver, running through it, will vibrate my entire house, I play it with a little 120W Hartke head from an old combo, it fills the room.

Horns are acoustic impedance matchers, they convert the energy from a speaker, which is more of a high pressure small surface area pump, and convert it into a lower pressure wider surface area driver. There's a lot of good, free horn designs out there, a couple have been used by bass cab companies, the rear loaded horn, and the old W-horn  which was used by Acoustic and Ampeg, and I'm gonna shut up now, because horns are just my thing, and I'm talking too much  


Edited for benefits and drawbacks

[hayseed]

Hemi-
the amount of info you possess is astounding! Thank you.
Would my 215 cab be "too much" low end running with the horns? Not enough punch?

[Hemisaurus]

There's a bunch of Sunn 215 horns, is your current Sunn 215 like the one in the diagram, in  which case you already have a horn.

Sunn did 215's with a port/horn mouth in the middle, and also with a port/horn mouth to the side. They also did a semi-W design where the drivers are inside a chamber and fire out

I have found running 2 Peavey 215's, one like the Sunn with a port/horn mouth in the middle, and one with each 15 in it's own space with a triangular port to be nice and bassy, but not too muddy, but then again, I run my amp with the crossover on, so that I cut everything above 400-500Hz out, I keep the tone on my bass turned way down, and I never change my strings.

I hate the sound of finger squeak, so maybe I'm not the right guy to comment.

The diagram above is the Center Port / Short Horn Mouth design

This is a Semi-W design folded horn


Side Port / Short Horn Mouth

[hayseed]

the one i was looking at is very similar to the SEmi W design though it had no red face logo on it in the center. It said SunnO)))) in the upper left(?) corner i believe. No grill cloth of any sort.