Folded Horn Configurations?

[40Hz]

The speaker you’re referring to is the Sentry IV, not an Eliminator. It was comprised of the dual 12 bass bin, a 90 x 40 horn with a phenolic MF driver and an ST-35 HF. Those were pretty good PA speakers back in the early 70s.

Beat me to it!

One of my early bands used modded EV Eliminator II cabs for our PA. We briefly upgraded later on to EV Sentry IIIs before finally going over to Altec-Lansing Voice of the Theater cabs which were A5s IIRC.

I have no fond memories of schlepping or wrangling those cabs for gigs. Today’s stuff is much lighter and sounds better for the most part.

 

[okcrum]

The ultimate challenge with folded horn subs for bass guitar applications is the path length differences in the low mids and mids, along with multiple throat reflections. If you were to look at the broad band impulse response, or look at signal coherency, you would see that the signal is made up of a bunch of smaller signals all slightly time offset from each other, along with increased distortion components (in the midrange).

Combine this with the necessary size for low frequency extension, and the weight, and the added cost for materials, packaging and shipping and you can see why they quickly fell out of favor as amp power got bigger.

If it were such a great solution, one of the hundreds of commercial bass speaker manufacturers would offer this kind of cabinet, but they don't (as far as I am aware of).

In a word, dispersion. It happens with any type of transmission line.

 

[chazolson]

V4-B cab, also one of my all time favorite cabs. I've only played through them twice that I can remember but what a sound, solid solid.

I had a V4B in high school. As I remember the cabinet weighed over 200 pounds and had a tow bar on the back. My school jazz band went to a competition in a school bus, and we unloaded at the top of a snow-covered hill in the middle of January. I lost my grip on the tow bar and that thing took off down the hill like a Nantucket sleigh ride. I yelled “look out below” as people scattered like bowling pins. All I could do was wait for it to lose momentum and stop. When it did I inspected it top to bottom. Not a mark on it. Built like a tank.

 

[cnltb]

Folded Horn Configurations?
Why?
Are we back in the 70s?

 

[dBChad]

Ashdown also had folded horns for a while.

I based my extension cab off of Bill FitzMaurice's Omni Full Range. I like it, but horns have this weird characteristic where you can stand close to them and barely hear them while being absurdly loud on the other side of the room. I had to learn to put space between me and my amp so I don't overpower everyone else. I also made some changes to BFM's original design based on experience (I added substantial internal bracing and offset the tweeter, using a 90x90 horn with the tweet instead. I still need to build a 1/4" spacer between the mid driver and the mouth of the mid horn, as the surround hits and causes a buzz), but I have a full range cab that plays down to an open B string and isn't very heavy. It is quite large (for a 1x12, pretty close in size to the Ampeg 410SLF) though.

It's a good cab, but it's different and requires a willingness to live with it's folded horn quirks to get the most out of.

 

[BassGreaser]

I love folding horns. The Acoustic 360 is a monster and can sound huge with enough EQ.

Now I’m playing through a Jack12 which has such an amazing clean and clear tone and can take EQ adjustments very easily.

I do plan on adding a second Jack12 to my rig for big stages/outdoor festivals.

 

[sawzalot]

There's no way in h*ll I'm moving or lifting folded horns onto the stage. I will, however, have the sound guy place subs under the stage and use a DI box into the PA with IEMs.

 

[Spent]

Many years ago my college roommate built a set of K Horns. It took months; a lot of precise measurements, clamping, gluing, etc. It was not a cheap endeavor, we had to use the best plywood we could get our hands on to minimize the chance of having voids in the wood for example. We also had to build our own crossovers because we couldn’t find anything on the market at the time (pre Internet). In the end they looked and sounded good, but only in a pretty big room. On top of that they weighed a ton (well, maybe 1/4 ton). We did it for fun, but I would never do it again. There are far better options out there.

 

[wagdog]

I love the sound of Klipschorns. There’s something about the LF presentation from a folded horn that makes them sound effortless. But as a player who moves his own gear? No.

 

[Stewie]

I wish I could get my Cerwin-Vega B36MF back. An 18 in back and a 12 up front. Once the guys at New England Speaker added an aluminum dust cap to the CV 12, the thing rocked. Not that bad to lump around either.

 

[agedhorse]

Anybody who has measured and analyzed the full range data from a folded horn would not characterize it as clear, low distortion or uncolored, nor do they have low frequency extension unless the cabinet gets VERY large. What they do well is high efficiency from about 70-70hz up to about 300-400Hz (size dependent)

 

[Slevage]

I wish I could get my Cerwin-Vega B36MF back. An 18 in back and a 12 up front. Once the guys at New England Speaker added an aluminum dust cap to the CV 12, the thing rocked. Not that bad to lump around either.View attachment 3333125

Did the dust cap add more high end?

 

[Stewie]

Did the dust cap add more high end?

Yes, I talked to New England Speaker(RIP) about adding a tweeter and crossover. The guy chuckled and told me to bring him the 12. He added the aluminum dust cover and told me I'd love it. He was right. The charge for this infinite improvement was " Have a nice day"

If anyone still has one of these monsters, give me a yell. I want it.

 

[Robert B]

I had two - the Ampeg V4B 2x15 and a Gallien Krueger 4x12 plus a front facing 10. Didn't like either one. Thundered off stage, but onstage sounded muddy.

 

[MIMike]

I think by the 80’s or early 90’s when average amplifier power went up over the 300W range, the efficiency gained by the folded horn design became somewhat obsolete.
Back when you had to compete with your guitar players 50 or 100w stack, the efficiency and size of a folded horn was actually somewhat desirable. Now, you can get much better sound and size with a modern driver in a modern designed box.
I don’t see any reason to go back unless it was purely for nostalgia or appearance.

 

[Rick James]

Now I’m playing through a Jack12 which has such an amazing clean and clear tone and can take EQ adjustments very easily.

Love mine as well, but it's not a folded horn, it's a straight horn.

 

[bobyoung53]

I had a V4B in high school. As I remember the cabinet weighed over 200 pounds and had a tow bar on the back. My school jazz band went to a competition in a school bus, and we unloaded at the top of a snow-covered hill in the middle of January. I lost my grip on the tow bar and that thing took off down the hill like a Nantucket sleigh ride. I yelled “look out below” as people scattered like bowling pins. All I could do was wait for it to lose momentum and stop. When it did I inspected it top to bottom. Not a mark on it. Built like a tank.

When I was a kid my band rented a V4-B cab with a 55 watt Ampeg B-25B head for an outside gig, I could not believe how good and loud that thing sounded, I got a gig with a much better band that day I think mostly because the guitarist in the band loved the sound of it with my flat stringed P bass. From what I remember is that it was about the size of an SVT cab but at least twice as thick, great rock cab. We had roadies so I didn't have to move it.
Another story, I got a call at about 6 or 7 o'clock one Friday night from a band who's bass player hadn't shown up while hanging around my favorite bar and had just done a tab of DSL. I showed up at the little club and there was a V4-B set up there which again sounded unbelievable with my flatwound P bass, I was jamming out with the guitarist in this three piece band, (I thought) drums, guitar and bass when all of a sudden a movement made me turn around and there was a key board player glaring at me. I hadn't even known he was there and had probably been playing all over him for who knows how long at least a part of the set.

 

[BassGreaser]

Love mine as well, but it's not a folded horn, it's a straight horn.

Rick, I just got schooled and glad for it! Not to derail this thread but after seeing how the Jack12 is built.. it’s interesting to see the internal construction.

I’ve only played mine in my small 500sqft studio apartment with a V4B RI and Gibson SG with flats. When boosting the low end the Jack12 gives huge rounded lows, but the ample mids help keep the SG from being muddy.

I’m looking to join a band soon to see how this setup does in a band setting and on stage.

 

[Ross W. Lovell]

Here's the problem: The wavelengths don't change, and horns are designed around the wavelengths they have to reproduce. If you want to achieve a particular low-end extension, the horn has to be long enough and the mouth has to be big enough. You really don't save much size by using smaller woofers. If you are okay with trading off low-end extension, then you could correspondingly shrink the horn.

In contrast, vented and sealed boxes can trade off some combination of efficiency and low-end extension in order to get a smaller box. So a small bass cab can theoretically go just as low as a big one (Acme Low B-1), but it will not be as loud. You can't do that sort of thing with horns.

THANK YOU!!!!

That explains why.

I never went by my sound on stage, just went by what our sound guy tells be. He gives me a feed of what it sounds like farther out. Seems to work in most situations.

 

[BergerHead]

Greetings All,

Any reason nobody makes a folded horn in either a 2 x 10" or 2 x 12", or 4 x 10" or 4 x 12" configuration?

Just for clarification that either 1 on top and 1 on bottom, or 2 on top and 2 on bottom.

There must be a reason for it. Just amused how a standard 2 x10 or 2 x 12 work, never had a folded horn enclosure smaller than 2 x 15"?

In fact there's no gain in moving air, the plus in compression ends at the horn's orifice.