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

[tuga]

A horn is a horn

 

[Chromatischism]

Page 25 and this thread is finally getting horny.

 

[JeanKazamer]

Quick question + if i may.

If size is not considered as a limitation, could a single horn design be effective from 100hz to 20Khz ?
Or are there some limitations that prevents this to be done .
( theoretically obviously, if we also omit any manufacturing difficulties )

By that i mean, if we had a driver that would be able to provide the required power from 100hz to 20Khz .
( again hypothetical )

thanks for your time

 

[tuga]

Quick question + if i may.

If size is not considered as a limitation, could a single horn design be effective from 100hz to 20Khz ?
Or are there some limitations that prevents this to be done .
( theoretically obviously, if we also omit any manufacturing difficulties )

By that i mean, if we had a driver that would be able to provide the required power from 100hz to 20Khz .
( again hypothetical )

thanks for your time

Maybe this will help: http://education.lenardaudio.com/en/07_horns.html

 

[Bjorn]

Quick question + if i may.

If size is not considered as a limitation, could a single horn design be effective from 100hz to 20Khz ?
Or are there some limitations that prevents this to be done .
( theoretically obviously, if we also omit any manufacturing difficulties )

By that i mean, if we had a driver that would be able to provide the required power from 100hz to 20Khz .
( again hypothetical )

thanks for your time

The sensitivity will drop significantly towards higher frequencies with a large horn and a large enough compression driver which is required to get that low. You need to split it up with different horns and drivers to maintain the sensitivity.

For home use though, we don't need 110-114 dB sensitivity in the highs, plus it isn't important for music material either which has much less high frequency content/SPL.

So a large horn that could cover from approximately 300 Hz till 20 KHz with a sensitivity of perhaps around 100-103 dB above 10-12kHz would be satisfactory. However, a compression that extends that low and with very low distortion in the highs doesn't really exist today. The best compression drivers can't really be pushed below around 500-600 Hz without raising distortion to audible levels or without loosing too much level in the highs.

It's possible by the way to manufacture a compression driver that can be crossed much lower, but one would have to sacrifice sensitivity to achieve that. For home usage, I believe that would be great choice. Crossing lower is a benefit, especially when space between horns is large.

 

[JeanKazamer]

Maybe this will help: http://education.lenardaudio.com/en/07_horns.html

Thanks was very educative, will keep in bookmarks

o a large horn that could cover from approximately 300 Hz till 20 KHz with a sensitivity of perhaps around 100-103 dB above 10-12kHz would be satisfactory. However, a compression that extends that low and with very low distortion in the highs doesn't really exist today. The best compression drivers can't really be pushed below around 500-600 Hz without raising distortion to audible levels or without loosing too much level in the highs.

Ok good info. So a horn could theoretically be used for such a large band ?

Unsure i understand the " The 3 octave rule for horns " .

If a horn throat is small enough to control the said high frequency and it then expends up the mouth of the horn ,
so how can it be to large for the high frequencies ?


"At 3 octaves higher the wavelengths are 1/10 of horn size and too small for the horn to direct them "

I understand that if the waves are too small compared to the horn size at some point they can't be directed anymore,
but if the pressure front starts at the throat doesn't it expends with the horn all the way through ?
( must depend on the rate of expansion of the horn i guess )

 

[Bjorn]

Thanks was very educative, will keep in bookmarks



Ok good info. So a horn could theoretically be used for such a large band ?

Unsure i understand the " The 3 octave rule for horns " .

If a horn throat is small enough to control the said high frequency and it then expends up the mouth of the horn ,
so how can it be to large for the high frequencies ?


"At 3 octaves higher the wavelengths are 1/10 of horn size and too small for the horn to direct them "

I understand that if the waves are too small compared to the horn size at some point they can't be directed anymore,
but if the pressure front starts at the throat doesn't it expends with the horn all the way through ?
( must depend on the rate of expansion of the horn i guess )

Yes it can be done with lower sensitivity as mentioned.

It can also maintain directvity up quite high in frequency. You can see the below with one single horn and a horizontal polar.

The main hindrance is really the driver.

 

[fredoamigo]

Bjorn​

what is the polar of which hp?

 

[Bjorn]

Bjorn​

what is the polar of which hp?

HP?

HP is an abbreviation for the following:

-Harry Potter (popular book series...you should know that)
-Hit Points (like in an RPG)
-Hewlett Packard (Computer Brand)

the short form of home party or house party

It's a horn I have. I've nothing more to share presently about it and it doesn't really belong in this thread. Was just showing that it's possible to have very broadband constant directivity.

 

[fredoamigo]

sorry for the abbreviation it's a translation error because in French it's haut parleur which means speaker in English

 

[MakeMineVinyl]

Quick question + if i may.

If size is not considered as a limitation, could a single horn design be effective from 100hz to 20Khz ?
Or are there some limitations that prevents this to be done .
( theoretically obviously, if we also omit any manufacturing difficulties )

By that i mean, if we had a driver that would be able to provide the required power from 100hz to 20Khz .
( again hypothetical )

thanks for your time

I have horns where the HF horn is crossed over at 500Hz, and this works extremely well. There's advantage in having a single driver cover all that range.

 

[Tom Danley]

Quick question + if i may.

If size is not considered as a limitation, could a single horn design be effective from 100hz to 20Khz ?
Or are there some limitations that prevents this to be done .
( theoretically obviously, if we also omit any manufacturing difficulties )

By that i mean, if we had a driver that would be able to provide the required power from 100hz to 20Khz .
( again hypothetical )

thanks for your time

The requirements for the high end horn driver and low end horn driver contradict each other for efficiency and directivity , hence you don't see any that cover that full band width at any significant level. Level times bandwidth in fact is a "difficulty factor" big time especially if your covering an audience, now days getting the needed loudness is not the problem but bandwidth is.

What one can do is make a CD horn that is multi-way full range horn but the drivers are close enough together acoustically to add coherently into one radiation (like sub-woofers do if placed next to each other) and the radiation enters the horn passageway where the rate of expansion is appropriate for the mid or other frequency ranges. That rate of expansion is part of what governs the efficiency raising impedance transformation.

Google "Synergy horn and Unity Horn" and see what this looks like, work that I began in the mid 90's.

By treating the horn passage as a singe acoustic element, driven each range where one has horn loading, you get an "impossible" full range driver on a horn that radiates as if it has a single driver with no lobes and nulls at crossover etc.

By having the mid and low drivers radiation enter via acoustic low pass filters (the ports and trapped volume) the harmonic distortion form each range is reduced compared to directly driven.
Most of these horns are much larger and more powerful than home speakers and are rarely seen, but sometimes they are visible.
Here is a case where they are visible but "not heard". They don't change the texture of the orchestra, just increase it's reach (as if moving the listening position closer)

https://www.prosoundweb.com/powell-hall-adds-danley-for-st-louis-symphony-orchestra/

Best,
Tom Danley

 

[Bjorn]

@Tom Danley
Could you give a brief explanation of the difference between a unity and a synergy horn?

I've recommended Danley horns for several occasions by the way.

 

[Tom Danley]

@Tom Danley
Could you give a brief explanation of the difference between a unity and a synergy horn?

I've recommended Danley horns for several occasions by the way.

Hi
The root idea for that started with a comment Don Davis made at a Synaudcon meeting about straight sided horns.
His comment was that they have a more "constant" directivity which was very desirable BUT had poor driver loading down lower in frequency and tied Don Keele's paper "whats so sacred about exponential horns" where he developed one of the first/ maybe the first constant directivty horn.

Fast forward to after the Space Shuttle disaster and my job at Intersonics working on a container-less manufacturing facility for the space station was rapidly dwindling down and then ended and i ended up having to start over in life one more time.
A friend bought the remains of the Servodrive business at Intersonics and challenged me to design a full range speaker to go along with those.

My focus had been on making various transducers at work and electrostatic speakers at home so I was starting over having to use existing parts.

Don's comment from several years before popped into my head AND so did the probable reason for poor low F loading. A horns rate of expansion is one of the things that effects how well or if it loads the driver with radiation resistance.

For example an exponential horn has a constant rate of expansion, a 30Hz horn can't expand any faster than doubling it's cross section every 2 feet but at 60Hz, it every foot and so on.

With the conical horn, the expansion at the hf driver is too fast to load lower mid frequencies and "the idea" was to couple drivers suitable for horn loading in the mid range IN the part of the horn that has the right rate of expansion for that mid frequency range.

It turned out that this worked was much better in several ways if one mounted the drivers on the outside of the horn and couple the energy in via acoustic low pass filters (the trapped volume under the cone and port mass).

The unity horn was part way where i wanted to go, they radiated a partial spherical pattern, like the ESL-63 I had repaired of my Boss's back at intersonics. These were marketed at live sound and got some minor use on a couple tours.

The phase shift from the crossover was still present, it was less than the electrical slopes would suggest but it was a single source in radiation pattern but not a single driver in the acoustic phase / time domain. In the years the company i worked for was selling Unity horns, my ultimate goal was to achieve something the late Dick Heyser described, a speaker that radiated from a single point in time and space.

The analogy is if one wants to use FIR filters to correct the phase response of a speaker, what one is doing is delaying everything back to the "slowest" or latest low frequency in question. Your latency and the lowest frequency you can correct to are both set by the number of taps you have,

The physical layout in the horn lends itself or can lend itself to a condition where the slowest to respond woofers are forward of the mids, which are forward of the hf in time.
The goal was to find a passive crossover which allowed the elimination of crossover phase shift so that it was in fact as if it has a single full range driver. What's needed are not a specific named slopes but one who's shape is one the computer fits. After all, where the sound from each source is 100% combined (being less than 1/4wl apart in the horn) what your dealing with is the unilateral addition of mag and phase of the upper and lower speaker and the mag and phase of the high and low pass crossover.

The solution was in the way the mid and lf ports were made. The mid section's ports were the hardest to figure out but it was possible to make one where the crossovers were invisible in the mag /phase and polar's.

The idea is to reduce the mass of the air in the port while retaining the needed area. This makes the acoustic low pass less steep and so less delay associated with it (just like how an electrical low pass does with slope). I guess in Dick Heyser's view i moved them forward in time without moving them physically

Since 2005 when we started the company I have the luxury of not having to design that many passive crossovers and that has left some freedom in where i can put things and more of them, but DSP doesn't free one from many of the acoustic relationships.
Hope that makes sense.
Best Regards
Tom

 

[JeanKazamer]

I have horns where the HF horn is crossed over at 500Hz, and this works extremely well. There's advantage in having a single driver cover all that range.

hi MakeMine, could you please elaborate or link to your loudpseaker design ?

sorry for the abbreviation it's a translation error because in French it's haut parleur which means speaker in English

oui mais haut parleaur = loud speaker ..pas simplement " speaker " i wonder which came first FR or EN ?lol

The idea is to reduce the mass of the air in the port while retaining the needed area. This makes the acoustic low pass less steep and so less delay associated with it (just like how an electrical low pass does with slope). I guess in Dick Heyser's view i moved them forward in time without moving them physically

That is some timing, i was just looking at your designs quickly yesterday when i stumbled upon Erin's stuff .
Thanks for sharing all this info with us , much appreciated .

Might i add a few questions for you ?

Not going to pretend i understand most of it, but the basic concept seems really straight forward and logical.

- Would having access to current digital sound processing change the way you would've designed ( or the side goals ) ?
- What are the compromises/downsides to the synergy/unity horn design ?

- Is your current work ( correct me if i am in the wrong here please ) the Hyperion , an " evolution " of your designs destined for home audio/HT
( smaller audiences )

I'm still confused as to how such small size horns can affect lower frequencies.

thanks all again, superbly informative and pleasant to read

 

[Duke]

The physical layout in the horn lends itself can lend itself to a condition where the slowest to respond woofers are forward of the mids, which are forward of the hf in time.

It seems to me that the internal geometry (like a tall pyramid) would result in the mid and low frequency ranges having local pressure maxima at the apex, where the compression driver's diaphragm is located. Does that happen; and if so does is it of any consequence; and if so does that constrain your compression driver choices?

* * *

Last weekend I attended a performance of the Nutcracker and they used big J-arrays for the sound. The lack of clarity was distracting to me, the sound quality barely adequate at best, and mildly painful on crescendos (even to non-audiophile family members). Made me wish for your Synergy Horns... while I've never heard them, the basic concept seems far superior. Kudos to you for taking a brilliant concept which was the epitome of "easier said than done" and finding a way to actually do it.

 

[Da cynics]

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

Damn that's some long ass thread in mate ... not going to read it all unfortunately :( So in the first few pages, i've read quite a few times something like " colored " or " canned " sound Could someone please explain how a Horn is supposed to be " coloring " the sound ? Are there any...

www.audiosciencereview.com

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

Damn that's some long ass thread in mate ... not going to read it all unfortunately :( So in the first few pages, i've read quite a few times something like " colored " or " canned " sound Could someone please explain how a Horn is supposed to be " coloring " the sound ? Are there any...

www.audiosciencereview.com

How about this perspective

A kind of Coloration
One of the factors that give rise to horn lover

 

[Bjorn]

Another cardioid speaker since the design was mentioned.

Horizontal polar:

Horizontally the beamwidth goes from appromixately 180° at 500 Hz to 100° at 10 kHz. At 7 kHz the directivity is down at 80°.

Vertical polar:

The vertical directivity suffers from lobing as expected.

Overall, the speaker is beaming. Not very badly horizontally, but a difference of 80-100° is quite substantial. Constant broadband directivity speaker? Hmm, not so sure!

 

[fredoamigo]

That's why I asked you where the polar you presented at the beginning of the page came from .

 

[Bjorn]

Dutch & Dutch 8c Speaker Review

Dutch & Dutch 8c Speaker Review

www.erinsaudiocorner.com

Kii Audio THREE Review

Kii Audio THREE 2-Way Studio Monitor Review

www.erinsaudiocorner.com

Erin has also understood the importance of measuring thermal compression.