Folded Horn Configurations?

[Downunderwonder]

the bottom chambers demonstrate nicely that moved air volume on its own means nothing but moved air volume.

The loudspeakers push the moved air volume into a "reduced" horn opening. While the moved air volume must remain a steady number the particle velocity will be increased according to the smaller surface of the horn opening.
As SPL is the derivation of particle velocity rather than moved air volume the efficience (respectively SPL) will be improved accordingly (this happens although the moved air volume does not change a bit).

In other wors the horn translates extreme SPL into medium high SPL which can be more efficiently transfered to the open air than what comes from a regular ported box arrangement.

 

[BasturdBlaster]

I have some LaScalas, 18 Sonic scoops, a Randall 215 bh, and years ago a Sunn 215 bh. The Sunn was magical, the randall not at all. The scoops and lascalas sound wonderful but they seem to produce an inherent "sweet spot".

Question... do all these type of cabs typically have no dampening anywhere for the sound to move as intended?

 

[ThisBass]

In other wors the horn translates extreme SPL into medium high SPL which can be more efficiently transfered to the open air than what comes from a regular ported box arrangement.

Just the other way round, the horn system (if proper aligned) helps to noticeable improve SPL versus the loudspeaker "moved air volume"

Ported cabs are very different animals and naturally way less efficient versus horn systems.

 

[Bflat]

While all I've read here is true you haven't lived until you play my 1951 pbass through this thing on 8 unbelievable, scares the neighbors dogs too

 

[ThisBass]

I have some LaScalas, 18 Sonic scoops, a Randall 215 bh, and years ago a Sunn 215 bh. The Sunn was magical, the randall not at all. The scoops and lascalas sound wonderful but they seem to produce an inherent "sweet spot".

Question... do all these type of cabs typically have no dampening anywhere for the sound to move as intended?

LaScalas, very nice cabs.
These don't provide lots of low end but, personally I very much like the dynamical "feel" with this cabs. Very similar impression is with the Klipsch horns

 

[BergerHead]

Line_array vs. horns

I think, that most of us are playing rather small to medium venues, so the very big space a horn-system becomes meaningful is rather seldom. Big audio-companies change over to array systems for they're less voluminous and weighty and ime much less tricky to get the sounds under control.
And to serve bassists, why do you think the SVT + 8x10" is still that successful in moving air plenty?

I did tech-jobs for Miles Davis, Supertramp and Jon Lord (with Daddy & the Steamers), for Klaus Lage Band (go Wiki) and dozens of local heroes ... they all hired me for accuracy & knowledge (my second name).

 

[BasturdBlaster]

LaScalas, very nice cabs.
These don't provide lots of low end but, personally I very much like the dynamical "feel" with this cabs. Bery similar impression is with the Klipsch horns

Ive had them since 1990, my uncle had the klipshorns. The bass is elusive but when in the right room/configuration, the sweet spot seems to exhibit a huge awesome bass, but its only in the "sweet spot",hehe

 

[ThisBass]

Ive had them since 1990, my uncle had the klipshorns. The bass is elusive but when in the right room/configuration, the sweet spot seems to exhibit a huge awesome bass, but its only in the "sweet spot",hehe

reminds me on an (long time ago) experience in my living room when I eventually noticed that the "sweet spot" is just about there where the chandalier is hanging from the ceiling. Nope, I didn't had any pleasure nothing at all to "sit down" on my chandalier to get the sweet spot from the HiFi cabs.

 

[JacklegBass]

Just stumbled on this thread.

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).

Great explanation. That mid-range distortion is probably what I heard back in the day with the Acoustic 301 cabinet being driven hard with a 370 head. It barked!! I loved it.

 

[BergerHead]

reminds me on an (long time ago) experience in my living room when I eventually noticed that the "sweet spot" is just about there where the chandalier is hanging from the ceiling. Nope, I didn't had any pleasure nothing at all to "sit down" on my chandalier to get the sweet spot from the HiFi cabs.

You know, all that Hi-Fi stuff is most overrated, as young i had a cassette-player over a little Hohner tube amp for years, this one had sweet spots all over the place; now i run a 1'000 albums in Itunes over a cheesy Altec Lansing 2.1 system and i'm perfectly happy with: music is what one gets in the ears, not where it comes out from.

 

[abarson]

True. Sorry, I forgot about the DR series. Have fun building one of those!

There's also the Jack series, which is a simpler build.

 

[ThisBass]

I did a couple of rehearsals in the early 80's with a W-horn cabinet (similar like the V4b W-horn cab).
The W-horn was powered with my SVT!
Personally I experienced the low mids and mids content way too "indirectly" which had been an experience that nicely approves the commentary of

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).

I had been a bloody young guy this time and (understandably) I did not know anything about science but, my only thinking was that the fridge provides a way more "practical" sound.

 

[Turnaround]

I recall reading about a no-compromise horn-loaded system someone built in New England back in the 1970's. The system was tuned to reproduce accurately 20 Hz. It was made of poured concrete for rigidity. The horn measured 11' z 11' at the mouth and was 16' deep (yes that's feet). Perhaps a bit large and heavy for most gigs no matter how much you folded it.

 

[BergerHead]

I recall reading about a no-compromise horn-loaded system someone built in New England back in the 1970's. The system was tuned to reproduce accurately 20 Hz. It was made of poured concrete for rigidity. The horn measured 11' z 11' at the mouth and was 16' deep (yes that's feet). Perhaps a bit large and heavy for most gigs no matter how much you folded it.

That's where the rabbit hops:

 

[BergerHead]

I did a couple of rehearsals in the early 80's with a W-horn cabinet (similar like the V4b W-horn cab).
The W-horn was powered with my SVT!
Personally I experienced the low mids and mids content way too "indirectly" which had been an experience that nicely approves the commentary of



I had been a bloody young guy this time and (understandably) I did not know anything about science but, my only thinking was that the fridge provides a way more "practical" sound.

This is my practical sound nowadays and believe me, it pretty smashes:

 

[byacey]

I built a couple of the BFM Titan 48s. They have a 13 foot folded horn path, the mouth is about 30" x 30" and will work from 45Hz up to 150Hz easily at 105dB = 1W@1m. Single 15" driver. If you try to work them higher in frequency, ringing starts to set in. Any kind of full spectrum horn loaded system will require multiple horns, each optimized for a specific bandpass.
Edit: These horns aren't as heavy as one would imagine; they are 30" x 24" x 48" and weigh about 100lbs.

 

[Ross W. Lovell]

I recall reading about a no-compromise horn-loaded system someone built in New England back in the 1970's. The system was tuned to reproduce accurately 20 Hz. It was made of poured concrete for rigidity. The horn measured 11' z 11' at the mouth and was 16' deep (yes that's feet). Perhaps a bit large and heavy for most gigs no matter how much you folded it.

Yeah, but with wheels and a tow bar you could put the band's equipment in it and tow it to the venue.

 

[bobyoung53]

The first time I heard the Stones Bill used a couple of those and he had plenty of bass !

I thought Bill almost always had a great sound, love the bass sound on Get Yer Ya Ya's out, all SVT's.

 

[bobyoung53]

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.

I've heard Klipschorns in a very large room out here in Peru, maybe 50' x 30', they are amazingly clear and reveal any defect in the source, if I had a living room that big I'd love to have a pair.

 

[agedhorse]

I recall reading about a no-compromise horn-loaded system someone built in New England back in the 1970's. The system was tuned to reproduce accurately 20 Hz. It was made of poured concrete for rigidity. The horn measured 11' z 11' at the mouth and was 16' deep (yes that's feet). Perhaps a bit large and heavy for most gigs no matter how much you folded it.

It's possible to design a horn to excel at low frequency AND efficiency, BUT it will be large, heavy, and will not do well with midrange.