• Welcome to ASR. There are many reviews of audio hardware and expert members to help answer your questions. Click here to have your audio equipment measured for free!

Horn Speakers - Is it me or.......

I think you put your finger right on the point there. A horn can always be called a waveguide, and a waveguide can always be called a horn.

In commercial speaker the two are used more as an indicator of what kind of feelings they want the reader to focus on, rather what kind of technology is behind the product.

If I was asked to make an official definition it would be this:

1: Loading is what is provided by a phase plug.

2: A waveguide is what shapes the waves coming out of the phase plug, and it may also start inside the phase plug.

3: The length of the wave guide from the diaphragm to where the acoustic impedance ultimately collapse, is a transmission line.

For something to be called a horn, I think it should in some way take advantage of all of the above. But that is not how the market sees it. It feels a bit Porsche Taycan Turbo, if you get my point?
 
What's the difference between horn and waveguide

To the best of my knowledge Earl Geddes, inventor of the Oblate Spheroid waveguide, was the first to use the word "waveguide" to describe a particular kind of horn. Here's how he put it:

"All waveguides are horns, but not all horns are waveguides."

When Earl first used the term, he intended it to denote horn curvatures that were produced by only a few specific equations. It has since come to be used well beyond his original definition, but generally the connotation is emphasis on achieving constant (or approximately constant) directivity.
 
When Earl first used the term, he intended it to denote horn curvatures that were produced by only a few specific equations. It has since come to be used well beyond his original definition, but generally the connotation is emphasis on achieving constant (or approximately constant) directivity.
I believe it is often used to avoid the negative connotation that has been attached to the term "horn" over the years. To read 'horn speaker" in some places you'd think they were the devils own designs. LOL
 
3. In general the longer the horn, the lower in frequency it can go.
Great explaination, just wondering about this one. Isn't that the longer the horn is the lower in frequency it loads and controll its dispersion?
 
the longer the horn is the lower in frequency it loads and controll its dispersion?
https://dbkeele.com/7-whats-so-sacred-about-exponential-horns/ abd some others on https://dbkeele.com/technical-papers-2/

or simply
Directivity Limit / Mouth Dimension (d):
\(d=\frac{K}{\Theta \times f_{\Theta }}\)
1791073532262.png

(where K = 2.54 × 10⁴ m⋅deg⋅Hz, Θ is the coverage angle, and \(f_{\Theta }\) is the low-frequency directivity loss limit)
 
Lu***er and some audiophiles love this:

Maybe that's why my life has run the path it did during my 32+ years of owning La Scala's :eek:
IMG_0691.JPG
 
Great explaination, just wondering about this one. Isn't that the longer the horn is the lower in frequency it loads and controll its dispersion?

Yes to the longer the horn the lower in frequency it loads.

All the dimensions of the horn plus the shape of the horn profile plus in some cases the compression driver's internal geometry all contribute to its dispersion characteristics.
 
Maybe that's
This midrange horn looks more righteous. The most unholy ones are those that are too long and have too small a mouth; they are that color the sound with pipe resonances and do not help with directivity control..
 
....I recently listened to some large horn speakers...I just don't get them.

Firstly they were clearly highly directional. Secondly, mid range seemed over emphasised with a "cuppy" effect...Lastly they were no more dynamic than any other large speaker.
Is it me? Am I biased?...Some rave about horns but it's lost on me.
...What are others experiences?
I have owned a few horn speakers but 90% of my experiences were selling them to mostly non-technical audiophiles from the 70s-2000s in regional specialty stores. During most all of that time Klipsch was the biggest selling speaker line by a good bit. Bose was usually the top brand overall but they were not close in traditional commission audio/video stores. So, I am familiar with seller and owner experiences.

On the buyer side, horn speakers, specifically Klipsch, were clearly differentiated in both concept and sound. Directionality and efficiency are easy to hear in a demo room filled with 20 other speaker pairs. Through most of this period movies and multi-channel audio were more likely to be demonstrated than two channel music, so precise localization, wide frequency response, and slam mattered more than cupped midrange. This is particularly true when powered through wattage restricted muti-channel receivers. For live music lovers, horns have a dynamic advantage at least when played through a retailer's switch box. They also more closely simulate pop/rock amplified concert venues as well as movie theaters both sonically and visually.

This may not align with what most at ASR consider to be "good" speaker performance, but consider. During this period component audio/home theater was more popular and more social than today. The neighbor with the best audio/home theater was where kids/parents often congregated. High on the priority list was purchasing speakers that sounded demonstrably different from what they had before (say, KLH or ARs) AND where their purchase decision would impress (and could be easily defended against) their neighbors. Klipsch advertised that their customer satisfaction, repeat purchases, and referrals were consistently #1 in the industry, and I have no reason to dispute that. Most customers loved them and they stayed out the door.

From the seller perspective the goal is telling a clear story, predict what will be heard, and then proving it with a demo. Of all components, loudspeakers are where the salesperson had the greatest impact (and where manufacturer's made sure commissions were the highest). Some of Klipsch's brand story has little to do with horns.... crazy genius Paul Klipsch, oldest U.S brand, Hope Arkansas. But the technical part, controlled directivity, high efficiency = low distortion, and wide frequency response were simple, consistent, understandable, and easy to demonstrate. They are louder, with more slam, with plenty of bass and treble in a retail demo room and pointing to the horns proved why.

Things have changed technically and in how speakers are sold. Current Klipsch products measure better and are only modestly horny. But questioning horn viability is a bit like complaining about the trunk space in a sports car. If the question is CAN horns measure well, certainly some of Amir and Erin's tests prove they can. If the question is "are they good", for many years the market said they were.
 
Thought I'd share the Synergy / Multi Entry Horn freq / phase plot I took of the SH50 DIY.
This is a 1m with acoustic damping around the area between mic and horn mouth.

Done with 3uF cap on HF (protection) and IIR DSP PEQs on the 3 way.
One 1st order XO on the high pass LF.
No XOs on the MF (relies on so called acoustic XOs (I believe they are called) and PEQ cuts only.

Compare with a phase wrapping trad XO system.
This I think is what @gnarly was refering to as a MEH strength.

Peerless RH 6dB (2).jpg


The slight rise in HF SPL disappears as you back off to the listening area.
 
Last edited:
If the question is CAN horns measure well, certainly some of Amir and Erin's tests prove they can. If the question is "are they good", for many years the market said they were.
Actually for many years, if you talked about horns you'd get that "cupped hands over the mouth" reaction and ridiculed for using them.

ASR is an antidote for this. That's why it exists.
Yep ;)
 
Yes to the longer the horn the lower in frequency it loads.
And, because the classic Leach equation assumes (for a horn in free space) the circumference of the mouth to equal the wavelength of the cutoff frequency, we find a larger mouth to correspond to a lower cutoff frequency.

However, that is for the functional horn section of the flare. Most modern home horns have an extra section added for the sole function of smoothing over the mouth to reduce back reflections that would occur with a sharply terminating mouth (such as you get with a classic exponential horn). Call this the 'curvaceous lips' section: it doesn't contribute to the horn's LF cutoff ability, because the horn function effectively stopped just before the lips started.

The only reason I mention this is because people tend to say that a (say) 500 Hz horn of type B needs a bigger mouth than a type A horn, but that is really because it has more generous 'lips' added to the functional horn section. We could cut the lips off and find we have two 500 Hz horns of the same mouth size.

cheers
 
Back
Top Bottom