Horn loaded loudspeakers

Many moons ago the UK distributor of Klipsch speakers loaned me a pair of La Scala speakers. They were big and ugly, with each speaker roughly the size and shape of an automatic washing machine. I am well aware of the problem of horn loading, and no doubt the frequency response curve was all over the place but the sound was utterly beguiling. The distributor wanted £800 for the pair (now retailing at £13,000) but in the end, they were just too large for my room. Are there any relatively compact horn loaded speakers of more modern design?

Problem is the smaller the horn the worse the sound becomes. I recently heard Klipsch la Scala and they sounded very nice. I was actually surprised as I imagined a cupped sound with bloated bass. That’s not what I heard and they were sat right in the corners of the room.

The problem with small horns is that they can’t play lower frequencies.

La Scala is almost a scam. Plastic horns, cheap drivers, simple cabinets, high prices.

The low frequency cutoff od horn speakers is related to the size of the horn mouth (and the length of the horn is related to that, too. It is some years since I studied the theory and contemplated building a pair (without getting past contemplation!), so this is just from memory: a horn in the corner of a room would need a mouth area of something like 0.75m2 to go down to 40Hz. (that is the mouth as facing you, which may include the room walls). And a lot of folding is required - unless you have the scope to build the rest of the horn outside the room, such as in the garden… Very close to (theoretically in) a wall but not in the corner and the mouth perimeter for 40Hz cutoff would be something like 1.5m2 m. For 20 Hz the areas would need to be 4x these!

The alternative is a higher cutoff and a sub.

On paper (I haven’t heard yet) I rather like the Fergusson-Hill FH1 acrylic transparent horns, which although big are near invisible - they only go down to something like 150Hz, and therefore need a special sub (special because going up a lot higher than normally required of a sub).

1 Like

Maybe try Avantgarde, from Germany. With tubes amps, they can sound amazing

1 Like

There’s also Living Voice, though I’ve never heard them.

Avantgarde, Living Voice. Both fabulous. Klipsch sound far far better than they used to but goodness they hog the space.

The most obvious would be Zu though. Not least because they target each speaker occupying no more than 1 foot square. The ability to produce at low volumes varies from speaker to speaker but the idea they can’t produce bass is daft. Certainly you might need a sub with the Druids in some rooms but not with any of the others.

Also a myth nowadays that they need valves.

1 Like

But unless I’ve missed something, Zu don’t have horn coupling as sought by the OP?…

Zu are effectively horns. The horn loading is unusual and they certainly don’t look like horns in much the same way you wouldn’t suspect there’s no crossover but… they will give the OP what they’re looking for.

1 Like

I heard some big Avantguarde on the end of a top end Accuphase a while back. It was an odd sensation. I mentioned on the forum that it was absolutely incredible and yet also somehow not my cup of tea. Vocal and piano presence was superb.

To @wordsmith What is the goal here? Do you have a very low power amp you are looking to pair with efficient speakers? I have a 10w tube amp and mulled Zu, Klipsche, Decware, and Omega. Finally for me it came down to Decware vs Omega and I went with Omega. Mostly because they were 98db and not horn loaded and were allowed to be positioned as close as 8" from a rear wall.


I’m confused! Zus have high efficiency drivers (I guess having very strong magnets), and, looking at the Druid, the tweeter appears to be horn loaded - but not the mid-bass. So I can’t see how it is in any way effectively a horn - horn loading is a means of coupling the speaker driver to the room air, and is different from just high efficiency. Incidentally, Stereophile’s review of the Soul Supreme also identified horn loading only of the tweeter, while finding that actual sensitivity was 91.5 dB/W - a lot lower than the claimed 97, and very considerably lower than a typical horn’s 105+ dB/W. What have I missed?

You haven’t Zu, are not horn loaded. But I’m trying to train myself away from being pedantic :upside_down_face:

I think of you read carefully around the Griewe model they use then there’s a clear element of horn loading in the design but Zu have a habit of shrouding that in incomprehensible babble which gets worse the more they expand on it.

Putting that aside, what the OP wants is a small speaker which gives them that sound they heard with the somewhat functional Klipsch. The assumption is that that’s likely obtainable from pure horns only. It is not and the Zu are the perfect example of that. Take a look at the Zu Omen or Omen DW. For the price and size they are astonishing.

Even if the speakers I’ve seen on Zu’s website have horns from the mid-bass with mouths concealed round the back, it is odd that it is not mentioned in their description, while the physics of horn loading suggests the cutoff frequency would be above the bass region.

As for what the OP is wanting to get from it, he/she will have to clarify - as I intimated in an earlier post, whilst horn loading maximises acoustic efficiency, it is not just about that: it is sometimes discussed in terms of impedance matching, with the result that horn coupling of a speaker driver to the room air does something beguiling to the sound that a direct radiator simply doesn’t. (But done badly the ‘honk’ can be awful!)

Isn’t Zu’s pyramid up the base more akin to Vivid’s and B&W’s reverse horn loading with the driver at the wide end?

Just be careful with horn loaded bass. There are really only two types out there in terms of positioning. Those designed to be set flush against a back wall and those designed to have a *minimum of 3 feet of open air behind them and not an inch less.

If the OP is after a Klipsch sound and Klipsch placement then it probably needs to be a Klipsch.

Hence some of us have suggested some other high efficiency non horn alternatives. Decware do some beautiful looking compact horns - really elegant and slim… but require just tons of air behind them. OTOH, they do some high efficiency non horn bookshelves too. As the OP has a Uniti Star though, I think the ask is not really about flea power friendly speakers and more about Klipsch sounding horns.

Inthecase of B&W. I think that’s a form of transmission line loading, with zero or minimal output at the end of the line.

As for the Klipsch sound, it brings back the name Voight from many moons ago… and of course, I think there was some Lowther corner homes, and, also a long time ago, Tannoy GRF corner horns.

Years ago in my twenties I has a pair of Lowther TP1s. Great big corner horns made in Bromley by Donald Chave. They were designed for the days of mono and if your room dimentions was the right size then they worked. Didn’t go that loud buy very efficient when driven by a QUAD 22 valve amps. Even with their size they lacked real bass.
I think the only place big horns worked well was in the cinema where size wasn’t a problem. Also amps in those days were low powered.
The much more compact Lowther Acoustas did a better job size for size.
The critisism for horns are/were they “honk” which has an element of truth especially when working too hard.

I think design has a big influence on tendency to honk. I believe the closer to being perfect horns with accurate flares, the less the tendency to honk. Introducing folds (essential for the base end in a domestic situation), causes departure from ideal.

There was a series of articles in the journal Wireless World back in, I think, 1974, which aside from making interesting reading, described, and included basic plans, for making two different domestic horn speakers. The name Jack Dinsdale rings a bell as the author. I’ve still got a copy stashed away somewhere, but it was certainly available online from various places just a few years ago. One of the designs was described as “no compromise” and was something like 4 feet wide 3 feet deep, six or 7 feet tall, and went down to 40 Hz, intended for wall placement. The other was quite a bit smaller and, designed for corner placement, but I think it hsd a higher cut-off frequency.

I wonder how John Crabbe of HFN got on with his concrete horns back in the c. 1960/70s?

1 Like