What is more accurate horns or cones

[Chris A]

Chris A, on 04 Jul 2014 - 1:19 PM, said: The use of horn-loaded drivers dramatically reduces the amount of motion that the driver is required to move in order to reproduce sound at the same sound power level (SPL) as that driver being used as a direct radiator. Chris

And this comes for free? No downsides?

John,

I assume that's a rhetorical question. Perhaps you should start your own thread on the specifics of what you clearly object to in your quoted statement.

I believe that you may have your question already answered...and that nothing that I can write will change it - and that's okay, but I don't wish to obliterate this thread that the OP set up (and hasn't yet returned to read) in order to argue fine points of horn physics or design.

I believe that the OP was asking a legitimate question wanting to know opinions of forum readers. In that spirit, my response is written.

Chris

Edited July 5, 2014 by Chris A

[Deang]

"I assume that's a rhetorical question. Perhaps you should start your own thread on the specifics of what you clearly object to in your quoted statement."

Are you serious? You're talking authoritatively on this topic, and you seem to have no problem fielding questions from others. So, if one agrees, they can stay in the thread, but it they disagree, they should start their own thread!

[Chris A]

"I assume that's a rhetorical question. Perhaps you should start your own thread on the specifics of what you clearly object to in your quoted statement."

Are you serious? You're talking authoritatively on this topic, and you seem to have no problem fielding questions from others. So, if one agrees, they can stay in the thread, but it they disagree, they should start their own thread!

I didn't see much to respond to in John's posting. (By the way, give John my regards if you talk to him, since I've not seen his reply or new thread by him yet. He apparently does good work on passive crossovers, too.)

Clearly a judgment call on my part to invite another thread. I don't have any issues with moving rhetorical questions elsewhere, or responding to the substance of a full reply here. Personally, I don't prefer rhetoric in this venue -- it has a history of creating bad blood that I like to avoid.

No authoritarianism yet. Just opinions, experiences, and the like.

Chris

[Deang]

John was asking a legitimate and serious question.

From Rod Elliott's site:

5.1.1 - Throat Power Vs. Size Vs. Frequency

For what it's worth (and because you'll find very little on the Net), the maximum acoustic power into the throat depends on several factors. First is the relationship of actual frequency to the horn's cutoff frequency. As the ratio of f/fc (frequency divided by cutoff frequency) increases, so does distortion for a given acoustic power per unit of throat area. A sensible upper limit for throat acoustic power is around 6-10mW/mm², meaning that a 25mm (1") throat should not be subjected to more than 3-5W. A 50mm throat can take 4 times that power, or 12-20W acoustic (see graph [1]). The amount of acoustic power that can be accommodated decreases as frequency increases. For horns intended for operation from (say) 800Hz and above, the normal rolloff of amplitude with frequency (as found in most music) means that the acoustic power also falls with increasing frequency.

If the conversion efficiency of a compression driver is (say) 25%, this means there is absolutely no point supplying more than 20W (electrical) to a compression driver on a 25mm throat, or 80W for a 50mm throat, allowing for a sensible distortion of 2%. Past a certain limit (which varies with frequency vs. horn cutoff), supplying more power creates no increase in SPL, but simply creates more and more distortion. The maximum power must be reduced as frequency increases. CD horns require HF boost, so can easily be pushed much too hard at high frequencies, resulting in greatly increased distortion.

Quite obviously, any horn that has a small throat must have limited power capability, and providing amplifiers that are (much) larger than needed for "headroom" is a completely pointless exercise. It is both convenient and accurate to consider the effect as "air overload".

According to a technical note from JBL [2], the situation is actually worse than the above graph shows. A 200Hz horn at 10kHz can readily generate 48% second harmonic distortion, with as little as 2.5W (electrical) input - a mere 0.75 acoustical Watts. As noted in references 1 and 2, this information was first determined in 1954, but over time seems to have been lost. As you can see, I'm determined that this will not happen.

_______________________________________________________________________________________________________________________________________________________________

Horns are awesome, I love the sound too. Since the sound of live music is normally reinforced with horn loaded rigs, it makes sense that horn loaded systems in the home do the best job of mimicking the live performance. When I came here what seems like forever ago, I had just dumped my Magnepans. Before that it was the Dahlquist DQ-10 and AR-11. I thought Heritage sounded terrible, and so did all of my friends, most who were locked into things like the a/d/s 1590, Vandersteen 2c, and other "refined" sounds. I never thought I would ever move away from the Reference line, because quite simply -- I thought using a horn for anything but a tweeter sounded awful.

I had to completely change the context in which I listened, and I think fully horned loaded systems are an "acquired taste". You have to embrace the sometimes raw and unfiltered presentation of horns, and leave behind the silky smooth and totally relaxed sound of most DR systems. I have yet to hear a DR based system that has the hair trigger transients of horns, and I think that's where the essence of the realism lies. Ribbons can do it, but again, the silky smooth way in which they deliver it just doesn't sound "realistic".

Mike Sanders of Quicksilver Audio used to listen to Magnepan, and then went to the Klipschorn. I told him I had done something similar, and I asked him what made him decide to make such a radical shift. He told me he had gone out for an evening of live listening, and after he went home to listen to his system, realized that it didn't sound anything like what he'd just experienced. He wanted that experience in his home.

There is a lot of talk about how much less distortion compression drivers and horns have than DRs, but that's not always the case -- it's an oversimplification of the issue. Horns are a convenient, reliable, and cost effective way of filling large venues with sound, using amplifiers that deliver something less than a gazillion watts of power. For the consumer, watts are relatively inexpensive (especially when one considers what the average watt might have cost back in the 50s), and the room that needs to filled is relatively small as well.

A DR based system capable of delivering high output with low distortion is not difficult to do, but it will be large and expensive -- and I don't think it will meet our true definition of accuracy -- which is "realism", close to recreating the sound of the live event. This means a sound that is somewhat raw and unfiltered.

Edited July 6, 2014 by DeanG

[Schu]

Just in terms that do not take into account distortion, don't horns have a tendency to cause more of what is known as beaming... As a function and of the directionality/focus of the lens itself?

meaning you have to get that under control to gain more listenable set up.

Edited July 5, 2014 by Schu

[garyrc]

Just in terms that do not take into account distortion, don't horns have a tendency to cause more of what is known as beaming... As a function and of the directionality/focus of the lens itself?

Does "beaming" = "high directivity?" If you want to sit off-axis by quite a bit, we would expect beaming to be a shortcoming. If you want minimum reflection from the walls, high directivity would be expected to be a plus.

But, as Heyser pointed out, Klipschorns (high directivity) are among the very few speakers that sound realistic from the next room. I've noticed that. We have a door and a pass through (both can be closed) between our music room / HT and the kitchen. With the Klipschorns turned up a little, it sounds like there are live musicians playing in the next room ... and when we close up the pass through and the door, it sounds like there are live muscians behind closed doors.

[garyrc]

You have to embrace the sometimes raw and unfiltered presentation of horns, and leave behind the silky smooth and totally relaxed sound of most DR systems. I have yet to hear a DR based system that has the hair trigger transients of horns, and I think that's where the essence of the realism lies. Ribbons can do it, but again, the silky smooth way in which they deliver it just doesn't sound "realistic".

I've said this before, but, in general, the audiophiles who were members of an orchestra I used to play in found that those players who sat in the direct path of the trumpets and trombones preferred horn loaded speakers, and those who sat off to the side of the brass, nearer the strings, liked direct radiators.

Most of the above agreed that tympani, snares, tamborine, triangle, orchestra bells, etc, sounded better on horn loaded speakers (in the case of tympani, fully horn loaded).

[Fjd]

Thinking about mid range wondering what is more accurate horns or cones particularly in vocals or is it personal preference.

Gearing up to build sub bass horns- thinking ahead a little to the mid-range and try to be setup to build cabinets for whichever way I go.

"Accurate" means different things to different people unfortunately. If your definition is "sounds most like the real thing", then I believe that the answer to your question will inevitably drift toward "horn-loaded", instead of "cone" (direct radiators). The reason for this is the relative absence of modulation distortion with the horn-loaded system. This means that you can play your music back even at concert levels without it sounding loud or compressed, unlike direct-radiator loudspeakers.

It is important to drill down into the actual definition of the person as it seems that from person to person, the definition of accuracy or neutrality seems to vary so much. In some respects, I'm not sure that I have seen a speaker manufacturer claim that "accuracy" and "neutrality" were not the primary goals or at least part of the goals. Many would say that the AR acoustic suspension speakers were correctly designed and "accurate."

I believe a key attribute for me is that using well-engineered horns and compression drivers, within their design parameters, is necessary to capturing the 'sparkle' and 'dynamics' in the midrange that people commonly associate with the very best horn systems; however, I'm not sure that any cheap PA horn and driver can be used in obtaining these results.

The use of horn-loaded drivers dramatically reduces the amount of motion that the driver is required to move in order to reproduce sound at the same sound power level (SPL) as that driver being used as a direct radiator.

Chris

And this comes for free? No downsides?

I'm not a horn designer or even understand all of the engineering, math, etc.; however, would be interested in the specific trade-offs that you refer to.

Are you referring to problems with diffraction, smooth dispersion and impulse response? Doesn't a true tractrix flair solve some of this, although acknowledging that the horns with the tractrix flair for only horizontal disperson still have problems on two mouth edges?

[garyrc]

Many would say that the AR acoustic suspension speakers were correctly designed and "accurate."

Good example. Consumers Reports magazine loved the AR series, but they defined "accurate" as "having relatively flat frequency response." They didn't even mention distortion. Most of my friends and I could not stand the AR speakers (including the top rated AR3a) because they sounded muddy compared to EV, JBL, Tannoy and Klipsch, all of which had superior transient response (and lower frequency modulation distortion, I presume).

[Marvel]

I've said this before, but, in general, the audiophiles who were members of an orchestra I used to play in found that those players who sat in the direct path of the trumpets and trombones preferred horn loaded speakers

Those who sit in front of the brass section probably having a higher degree of hearing loss, too.

Bruce

[Don Richard]

Downsides? Sure... size and cost.

[Ski Bum]

And low WAF.

[Islander]

Even PWK's first wife Belle wasn't crazy about the looks of the La Scala, so he came up with the Belle Klipsch. Presumably, she liked its looks much better.

[Chris A]

...When I came here what seems like forever ago, I had just dumped my Magnepans...

...Mike Sanders of Quicksilver Audio used to listen to Magnepan, and then went to the Klipschorn. I told him I had done something similar, and I asked him what made him decide to make such a radical shift. He told me he had gone out for an evening of live listening, and after he went home to listen to his system, realized that it didn't sound anything like what he'd just experienced. He wanted that experience in his home...

I owned and listened to Magnepan MG-IIIa's for a couple of decades before acquiring used corner horns from Gary Shinall, on a lark when empty-nesting finally arrived when we again had time for listening to music seriously. I invested in Klipsch Jubilees a couple of months later and I've never wanted to listen to planars again. I regard the Jubilee purchase as the best acquisition I've made so far based on the number of hours/day listening to them since late December 2007.

I agree with your friend: live acoustic music is the reference that I use. I recommended horn-loaded loudspeakers here not because I wanted to make my old recordings somehow sound better than they are. It's been my experience that bad recordings are bad recordings--and they don't get better or even more desirable with time. Better loudspeakers always make the listening differences between good and poor recordings even greater. C'est la guerre.

And the system (sound reproduction system, including the room and the listeners) is no better than the weakest link. In my case, I've found that the weakest is the recordings themselves 99%+ of the time.

Chris

Edited July 6, 2014 by Chris A

[Schu]

...When I came here what seems like forever ago, I had just dumped my Magnepans...

...Mike Sanders of Quicksilver Audio used to listen to Magnepan, and then went to the Klipschorn. I told him I had done something similar, and I asked him what made him decide to make such a radical shift. He told me he had gone out for an evening of live listening, and after he went home to listen to his system, realized that it didn't sound anything like what he'd just experienced. He wanted that experience in his home...

I owned and listened to Magnepan MG-IIIa's for a couple of decades before acquiring used corner horns from Gary Shinall, on a lark when empty-nesting finally arrived when we again had time for listening to music seriously. I invested in Klipsch Jubilees a couple of months later and I've never wanted to listen to planars again. I regard the Jubilee purchase as the best acquisition I've made so far based on the number of hours/day listening to them since late December 2007.

I agree with your friend: live acoustic music is the reference that I use. I recommended horn-loaded loudspeakers here not because I wanted to make my old recordings somehow sound better than they are. It's been my experience that bad recordings are bad recordings--and they don't get better or even more desirable with time. Better loudspeakers always make the listening differences between good and poor recordings even greater. C'est la guerre.

Chris

And this is my PERSONAL definition of "Accurate"...

[russ69]

Horns are awesome, I love the sound too. Since the sound of live music is normally reinforced with horn loaded rigs, it makes sense that horn loaded systems in the home do the best job of mimicking the live performance...

I had to completely change the context in which I listened, and I think fully horned loaded systems are an "acquired taste".

I completely agree. I also don't just drink white wine, I like horns for what they do best, planers for what they do, and cones for their strengths. You don't have to pick just one and try to adapt to it.

[garyrc]

And low WAF.

My wife loves the look of the Klipschorns ("they look elegant"), and she can't see the center channel Belle because it is behind acoustically transparent (with a little help from Audyssey) wall fabric.

[jason str]

Growing up listening to horns everything else sounds bland.

Horns deliver realism and minute details that other types of loudspeakers just cant deliver.

[joshnich]

To fill my large room horns are awesome. I enjoy just as much my little single driver speakers for near field. Each have a place. I wouldn't use one in place of the other for what they are used for.

[DrWho]

"I assume that's a rhetorical question. Perhaps you should start your own thread on the specifics of what you clearly object to in your quoted statement."

Are you serious? You're talking authoritatively on this topic, and you seem to have no problem fielding questions from others. So, if one agrees, they can stay in the thread, but it they disagree, they should start their own thread!

Thanks Dean, I totally agree....and props on the horn throat distortion too. Although I think your f/Fc is missing the math a bit - what really matters is the frequency content traveling through that throat (music has lots happening at once). The implications are still the same though, so I guess I'm nit picking.

You could probably add how the horn breaks up the sound wave too, and you get all those nasty reflections that impart the hand cupping sound.....even on good horns, there's still a hint of it.

Compression drivers ring and the sound of the flexing diaphragm just isn't as pleasant as your direct radiator. It doesn't help that the horn xover is complicated and never perfect, so you really gotta stretch the bandwidth of the driver - which just makes its sound all the more apparent.

The folded bass horns are even more cavernous sounding and have acoustic resonances in the pass band that you never get with direct radiators.

All that said, I still prefer horns for the reasons mentioned. I think where they really shine is with really thick music where any extra tones really muddy things up.