Why not horns?

I read the following statement wrong so I'll try to answer it again.

"You are comparing 2 amplifiers that obviously have differences other than max power and saying it is definitely because they have more power. It seems you jump to a lot of conclusions."

Actually, I made no such claim! I offered this example as a counter to your implication that simply because a speaker HAD a ton of amplifier power that it NEEDED the power. I simply offered a concrete example as to why Avantegaurde WOULD install a 250watt amp versus the argument that it NEEDED one.
My initial response to this statement was offering a reason as to why the amp with more power would sound better.

Herman, we can use flea power because of the efficiency of the drivers that can be used with horn loading. Horns are a device that give a certain amount of gain with a particular driver. The efficiency can be enhanced with a horn, but the horn itself is not what dictates the power needs.

I understand, and am not irritated by physics, that with a longer horn and smaller throat, a different drive will yield different sound. But to say that something is not a horn because it uses 200+ watts is not accurate. I guess you really said "true" horn. How about saying "a non-folded horn". That I believe I can agree with.

I can theorize that the seismics are about 101-102 db. The drivers are 95 dB and I can guess to at at least a 6db gain. But this is a bass horn, ~20-200 Hz. There is quite a bit of energy needed to get from 40Hz (your horns) down another 20, and mine are a folded horn which I can move from room to room if needed.

The rest of the horn system is easily 110+ dB and that is what I referred to in my last post. I'm biamping this upper end with two, 50watt amps. They rarely get beyond the first watt, except for the amp driving the mid-bass. It probably does get a bit of a workout from the 105-106 db mid-bass. There again using a large driver because it is a 3/8 horn. It's not even worth talking about the mid-range and tweeter horns.

There is a lot more to creating a note and creating a note that sounds as big as the instrument which originally created it. This is subjective, naturally, based on the music that each of us prefers.

to all,

Did someone actually tell me that all horns are not alike? ;-) Really? I would have never guessed. I thought that all through this thread I have been pointing that out. My way is not the only way. Neither is yours.

Duke .. LOL....

Duke are you saying those that dislike horns cannot pick them out in a blind test , good Man , you know your market,
Stevie wonder must have a Pr then ? ..........LOL

Dukey maybe you have yet to hear good hi-fi, hence the horns ...)

Seriously i'm sure you can respect it does not work for everyone and with good reason.

Most dealers have had the same bad experience for years, just stick you head into one of their demonstration room's ...

Deaf comes to mind !!!

Prez, so one watt to the basshorns produces 109dB at one meter?

Identical in every way expect the fact that the monobloc has paralleled outputs.

Identical except it has more power and a different output impedance and just about everyone who has tried it says running a stereo amp in mono changes it's sound even if they are played to the same level.

BTW, If you take a 75W amp and run it as a monoblock you get twice the voltage swing so 4 times the power, not twice. What amps were these?

Wes, that is what Dan told us, I was asking him to clarify if that was what he meant.

I believe the presenter in the Cathedral room (the designer of the speakers I believe) told me it was a vintage Fisher tube amp of some sort, but it was tucked away and I did not see it.

The source was digital, a Marantz player or something along those lines, but not certain.

I wish you could edit,

Prez, you said the outputs of the amp were parallel to double the power. It doesn't work that way. Please clarify.

.

Herman ,

That would be bridged for 4 times the power and not necessarily just because it is a monobloc.

What frequency are they rating the bass driver @ 1 K, 100 hz?

Wes, I know nothing about this bass driver. You need to ask Dan.

I understand what bridging an amp is. If you bridge a 75W amp you get 300 watts if the power supply can handle it, not the 150 stated by paralleling it, whatever that means. Perhaps I misunderstood what he meant, that's why I asked him to clarify.

.

Required viewing to understand this madness !!!!

http://www.youtube.com/watch?v=xs1aUws0Lrs

The experience in the Cathedral room was way different than in the room with the mega gear driving those horns.

Cathedral used a modest CD player and a vintage Fisher tube amp as I recall. Some classical piano and more pop pieces (carole King) were played while I was there. The Cathedrals were very pleasant and clean sounding and easy on the ears, though volumes and dynamics were not to the max with that setup and source. They indicated they were going for more of a "vintage" type sound. I could have stayed and listened in this room for much longer than the 20 minutes or so I spent, but I still had some ground to cover before event end.

The mega gear room was tweaked to the max for phono, and the phono stage designer (Dynamic Sounds) was present. The phono rig there was most impressive, not a trace of noise on those ultra sensitive horns and a quite nice and vibrant presenation overall to boot, but that's another story for another thread. Some digital was played using an Accuphase player, but this was way less impressive in that setup.

Bridging and paralleling are two very different things.
Bridging effects the voltage. Parallel does so with the current. If a design can allow for paralleling you double the current thus doubling the wattage. You also cut the output impedance in half thus increasing your damping factor.

The question of whether or not a set of three basshorns will reach 109dB sensitivity is not as simple as measuring 1watt at 1 meter. Measuring actual sensitivity in the real world is a little more complicated. And the whole 1w/1m standard is very misleading!
1w/1m works adequately for comparing drivers and most simple one to four way dynamic designs. But for planar speakers and line arrays it is basically useless. A typical speaker will measure a particular level at 1m and that level will drop off as a function of distance. A planar or line array will measure one thing at 1m and then INCREASE as a function of distance up to a point. This is because it takes a little space for the entire surface of the planar or all the drivers of a line array to combine.
In the same way, three bass horns are effectively a line array of 6 different 12inch woofers. This takes up nearly eight feet and will only combine at a distance of about 10feet away or more. Therefor, in order to accurately define the actual sensitivity of the entire system you have to measure both the upper frequency horns and the basshorns are the same distant spot. You measure the upper horns to get their true sensitivity at that point and then set the basshorns so that they are of equal SPL at that same spot. THEN you measure the amplifier output. And only THEN do you have a real estimation of the sensitivity of the entire system.

Prdprez, that guy who hated horns was talking about mine at Lone Star 2010. The speakers behind the curtain in the first example were GedLee Summas.

Until you've heard speakers designed or inspired by Earl Geddes, you haven't heard all there is to hear in the world of low-coloration hornspeakers. And at least one of his students got some press a couple of years ago: a Golden Ear Award from The Absolute Sound.

Duke

Weseixas wrote: "Duke are you saying those that dislike horns cannot pick them out in a blind test?"

I'm saying that a high quality, low-coloration horn system doesn't sound like a horn system.

Duke

Duke: Ah, yes! I remember now. Then again, your contribution has thrown into the light that we should be careful in defining exactly what "horns" we are talking about.

Your Dream Maker is only a "horn" from 1.7K up. It's not a wonder it would sound so smooth. the majority of all instrument fundamentals as well as all voices aren't coming form a "horn" at all! (if I understand the design correctly)
I would think this would be a major difference between it and something like an Avantgarde! If not, please do explain. I am curious!

My take on the blind test was that the listener was noticing all of the same similarities that seperate Stats and Horns from typical dynamic speakers. It doesnt surprise me one bit that he guessed the way he did.

I've seen the same thing with the (effectively) 100dB Scaena speakers being compared to Magnapans!

Until you've heard speakers designed or inspired by Earl Geddes,

I would love to hear geddes stuff, but how ? Where?

From past viewing Geddes stuff are not really horns but uses a sort of waveguide , so they would lack the same coloration associated with typical compression drivers IMO.

Dats the problem... a guess !

06-14-10: Prdprez
My take on the blind test was that the listener was noticing all of the same similarities that seperate Stats and Horns from typical dynamic speakers. It doesnt surprise me one bit that he guessed the way he did.

Duke,

Are you saying the Summas are electrostatic like in there presentation ?

Ditto to Weseixas!

I was just thinking the same thing about Duke's speakers.
Isn't more of a waveguide than a horn?

Hey Mapman
What amp was being used in the Cathedral Audio setup?

I do think this is his products !

DR Earl Geddes : http://www.ai-audio.com./productsesp.html

Pdprez, good call - I hadn't made a mental distinction between "horn system top-to-bottom" and "horn system over part of the spectrum". And your understanding of my designs is correct; you also get extra points for coming up with the right name for one of them!

I have no hands-on design experience with top-to-bottom horn systems, and would think that they'd be far more difficult to do well. I'm too chicken to even try.

Weseixas, a waveguide (as Earl uses the term) is a type of horn optimized for low coloration and well-controlled off-axis radiation characteristics. If you're willing to distinguish a Geddes-style waveguide from the rest of the horn world, then you and I are quite likely to end up on the same side here. And what fun would that be??

Cheers,

Duke

From Geddes :

The waveguide features a state of the art HOMLess Refractive Waveguide PlugTM which minimizes high order modes which cause colorations.

I'm on the side of good sound Dukey !

Earls science is pretty big, hard to match him there , but this is audio, there are fundamental things that i do disagree
with Dr Geddes on and until i do get a taste of his soup i will hold on to such.

regards,

I use a Geddes-style waveguide on most of my designs, but it's not the same as the ones he uses. Nor am I using his patented refractive waveguide plug. In my more recent/less expensive models, I'm using what might be called a "waveguide-style horn", which is considerably more of a challenge to get good results from.

If either of you will be at RMAF, come on by my room if you get the chance.

Duke

06-14-10: Audiokinesis:

If either of you will be at RMAF, come on by my room if you get the chance.
------------------------------------------------------

RMAF ? R.eally M.ad A.udio F.arts .. -)

What models are you displaying ?

Before I completely lose my train of thought (again), let me do a quick tie-back-in: The conical horns Bill Woods (designer of Macrojacks's speakers) uses are arguably what might be called "waveguides". And when Bill Woods came by my room at RMAF several years ago, he subsequently referred to my waveguides as "conical horns". Maybe neither perfectly fits the defnintion of the other, but they are conceptually and sonically very close cousins.

Duke

Here's an excerpt:

Conical Horn Geometry

I’m often asked how horns differ from one another, and also how different types of horns differ in sound and design, such as exponential, tractrix, and new versions of these which carry the names of their designers. I’ve put together some observations, backed up by actual frequency response curves and measurements, so that people can decide for themselves what types of horns would work best for them.

The above are the words of Bill Woods. If you are genuinely interested in knowing something about horns, this article is available in its entirety on the Acoustic Horn website.

I am not an expert but I can tell from reading these comments that many of you are overestimating your understanding of the subject. Do yourselves a favor and get the real info from someone who has devoted his life to this study.

Horns differ tremendously and Bill has as good an understanding as anyone of how and why this is true. Let him explain it to you. He's a scientist with a degree in industrial design and a lifetime of trial and error experience.

Those of you making categorical pronouncements about the limitations of horns - all horns - demonstrate the greatest need for education.

prez, I think you are bit off base.

Bridging and paralleling are two very different things. Bridging effects the voltage. Parallel does so with the current. If a design can allow for paralleling you double the current thus doubling the wattage.

Assuming you aren't trying to draw so much current that the supply voltage sags then the max power is determined by the voltage rails. If you parallel two amps you get the same maximum voltage before clipping. If you get the same maximum voltage you get the same maximum power.

Two 75 watt amps with a given gain in parallel is a 75 watt amp with the same gain but capable of delivering more current into a low impedance load so it won't sag and clip as easily. Now that might explain why it sounds better.

a serious argument could be made that it is better to use 6 individual drivers to achieve the same sensitivity of just one and a huge horn due to the way the 6 different ones will average out their non-linearities.

Interesting theory but again, a little off base. You think if multiple drivers have different distortions that will add up to less distortion? You can't average out distortions.

A + B + C + D + E + F is less than A ??? I don't think so.

Now if you told me that 6 would distort less because each is working 1/6 as much therefore distorting much less then I would go for that.

I hate to be blunt but if you don't understand some of these basic concepts it kind of puts your other conclusions into question.

.

Herman !

Prez said lower distortion for the same sensitivity, with multiple drivers vs 1 , this is correct!

1. Transient Distortion
2. IMD
3. THD

all will be lower vs a single driver !

You then went on to explain it in , well, a simpler term , coming to the same conclusion that you originally denounced.

LOL...

Regards,

Good Gawd Herman!!!

Sit back, take a breather and learn something!!

First of all, Voltage X Current = Power (Watts)
This is basic basic stuff. If you double the current you double the power!

And what I said about distortion is also true. I mean seriously, your most recent post calls into question your very ability to remotely discuss these things.

In all seriousness. Go ask a Electrical Engineer. You'll find that everything I've said about this stuff so far is true.

I don't mean to be crass, but Sheesh!

"Now if you told me that 6 would distort less because each is working 1/6 as much therefore distorting much less"

YES!!!! That is EXACTLY what I am saying!!! (Among other things)

What are YOU reading???

"Those of you making categorical pronouncements about the limitations of horns - all horns - demonstrate the greatest need for education."

I always love the smug responses.
I'm not sure who you are calling out here. But everything I've ever said is based off of extensive and first hand experience. I'm not and never have claimed that it's impossible to create something from a horn. But to date I have yet to hear one that truly impressed me overall.
I'm not out there trying to design one therefor I really see no reason why I would need more education on the matter.
When I hear one I like it will change things.

You then went on to explain it in , well, a simpler term , coming to the same conclusion that you originally denounced.

LOL...

I did not denounce his conclusion. I denounced his reason. I said something complete different LOL !!

Prez, I read exactly what you wrote. You said "6 different ones will average out their non-linearities. ."

That statement is false. Nothing averages. To average something you must add up each one and divide by the total. They produce less because they aren't driven as hard. Each one produces much less so the TOTAL is less. That is in no way, shape or form an average. That may be what you meant but that is not what you said. I'm sorry but I am not a mind reader.

Good GAWD !!

There is a lot I don't know about electronics but after teaching it for 10 years I do have pretty good grasp on the basics. Since you want to be condescending let me explain it to you in the simplest of terms.

To produce 75 watts into 8 ohms an amp must have rails of about plus/minus 34 volts. That give you peaks of 34 volts which is 25 Vrms. Square that and divide by 8 oms and you get 75 watts. P = V squared divided by R.

When you put things in parallel the voltage stays the same.

If you put 2 amps with 34V rails in parallel you get an amp with 34V rails.

Same volts = same watts.

You are correct that V x I= P.
Also V divided by R = I
With the same R and the same V you get the same I
With the same I and the same V you get the same P

He didn't change the speakers so the R stayed the same.
Sill got 34V peak amplifiers so that stayed the same.
Same V same R same I same power.

Care to retract your admonition to "Sit back, take a breather and learn something!!"

.

If you take 6 different drivers, unless they have perfectly linear transfer functions, they will all have slightly different responses. If they all have the same input signal their responses should smooth to a more linear response.
It may be to small to be audible which is why I stated that it MAY be argued to be better. But it doesn't change the fact that these differing nonlinear transfer functions should become more linear as a whole.
The reduction in distortions, which is what Weseixas picked up on, should have been a little more obvious.

And honestly, I'm not going to retract anything either. I don't doubt that you (Herman) teach electronics but I am still a little wary as to why, when I said "parallel", you assumed bridge and didn't seem to know the difference.

I had written a lengthy explanation to all of this but Audiogon rejected it for being too long. This is probably a good thing.
So I'll just sum up in a few lines.
First, your equations make sense for DC and purely resistive AC. But this is not how drivers directly coupled to amplifiers behave. The whole argument arose from an example I gave as to why Avantgarde would chose to use a high power amp on an already sensitive speaker. This had nothing to do with the assertion that the basshorn could not be sensitive BECAUSE it has a large amp.
Because this line of arguing really has no relevance to the thread. And because we seem to be on different verbal wavelengths here. I'll simply refer you to Balanced Audio Technology for an explanation on why they list their Vk-75 as a 75watt amp and why they list their Vk-150 as a 150watt amp. Even though the only difference between the two is the internal paralleling of the inputs and outputs and a different nameplate on the VK-150. Any more explanation as to why this matters on a complex load I leave to them.

Cheers, and goodnight, for now.

I completely understand the difference in parallel and bridged.

I completely understand that parallel amplifiers cannot double the power output. I remain confused that you insist they do.

I saw nothing on the BAT site that explains why their amps do this. Maybe I missed something.

I accept your apology

.

Weseixas asks: "What models are you displaying [at RMAF]?"

Duke replies: My current plan is to show a bipolar model called the Cloud Chaser. It's fairly new - not up on my website yet - but is described in my Audio Circle forum.

If you take 6 different drivers, unless they have perfectly linear transfer functions, they will all have slightly different responses. If they all have the same input signal their responses should smooth to a more linear response.

Sorry, a complete load of crap.

Are you serious? You add up a bunch of errors and the total error is less than any individual error?

You've already embarrassed yourself with your theory about parallel amps. Might be better to retire now and save face.

.

I have a suggestion, I think all those that slate Horn speakers here who have not divulged what speakers they are running should.

I'm running 1000 watts on bass horn 550 on mains. My horns do run fine on low power. But to think only low power is best for horns is wrong. Many audio designers I know run hi power on there horn systems. Doesn't mean I use all this power but the sound quality's of the amplification I choose compliments my horn system.

Duke your loudspeaker design is interesting and I'm sure very well thought out but the name darn your as bad as me picking them ;) Cloud chaser..I was thinking of pimping your bi pole design if I do will name it the DL BP after you. I started this when we chatted awhile back but didn't want to step on your toes. But read where you do not care if others use your idea. I have what I thought is a great idea for cabinet to allow better bipolar effects and image. So far results are very good. Might be able to break the $2500 price point with this design.

And so it goes ............

Has anyone taken the trouble to read the Bill Woods piece I recommended?

It's quite possible that some of you are well informed on the subject of horns but I have heard from no one so far who wouldn't benefit from Bill's expertise.

Calling me smug is powerful stuff but unlikely to move you any further along in your understanding of horn function and the distinctions that exist from one concept to the next.

I can never figure out when Duke or Ralph post responses to threads and always give clear and precise answers to the post some people seem to miss the points they are trying to make.

JohnK. there is no definitive definition of a horn, but your bass horn is a completely different beast than what most of us are discussing here,,,, a front loaded horn to increase efficiency.

Your back loaded horn derives a huge part of it's output directly from the 4 drivers mounted on the face of it with reinforcement from the back. That is a very different scenario from a front loaded bass horn that must be much, much longer to be efficient.

It's not that one is right and one is wrong, but they are different. Curious what the efficiency of your bass cabinet is?

Jack, I finally got the web page to come up. It is curious that we have Bill telling us how wonderful his horn is with no mention of an EQ and Duke saying they sound like a megaphone without proper EQ. I didn't go back and read the whole thread so I'm going from memory here so maybe I missed something but if the horn does require EQ to sound good you would think the seller would mention that.

"Calling me smug is powerful stuff but unlikely to move you any further along in your understanding of horn function and the distinctions that exist from one concept to the next." -Macrojack

If I really don't care about horns one way or the other. And if I don't really care because I have yet to hear one that I truly like. Why do I need to educate myself? I don't care that much about line arrays either. Do I need to also educate myself about them? I'm sure there is some professional out there who could show me all sorts of math as to why they are the bees knees. Perhaps my perception of "smug" was a little strong but it's what I perceived when confronted with the idea that I need to "educate" myself more because I don't "like" horns. They don't suit my taste visavis other designs. I've never said they were an invalid concept.

Prdprez - There is no need for you to educate yourself about horns unless you want to make a useful contribution to this thread or you are considering ownership for yourself. As you you've established clearly that you have no use for horns, pray tell, what use have we of you? Why are you presenting yourself so emphatically in an arena where you have no interest nor expertise? Seems self-serving and insincere at best.

"I completely understand the difference in parallel and bridged.
I completely understand that parallel amplifiers cannot double the power output. I remain confused that you insist they do." -Herman

Then why did you assume bridge when I said parallel? And why did you need me to make the distinction? Whatever, its neither here nor there.
Laying in bed last night it dawned on me that every time you (herman) refer to "power" you are actually speaking of of "gain". Basic Watts versus dBW. Suddenly it became clear why you were so adamant that a basshorn didn't need 250W of power.
Well obviously it doesn't "need" that much GAIN. And because it has a built in volume control it is unlikely that it will ever USE that much gain. Never the less, being that the driver is NOT a resistor but has a complex impedance curve, the designers probably found a 250W amp useful.

As I said before, you're going to have to talk to BAT directly if you want any more explanation on their specs.
But your perspective makes better sense to me now thinking in terms of GAIN rather than total available power and why you aren't seeing what I've been trying to say here.
A horn may only need a small amount of gain but no speaker is a pure resistor and very likely will benefit from increased power in terms of current.

BTW, I offered no apology. Taking it truly is smug.

"Sorry, a complete load of crap.
Are you serious? You add up a bunch of errors and the total error is less than any individual error?"

Yes, absolutely serious. And it beguiles me as to why you don't get it.
I didn't use the term "errors" but since you do, in this sense "error" would be any deviation from FLAT. Maybe I should have said "frequency response" instead of transfer function.
But this doesn't change my assertion. Which, by the way, is provable with actual measurements.

In simplified terms, take two drivers with the same frequency range but whose precise deviation from flat response within that range are slightly different. If you add them to the same signal but reduce the gain to each by half (3dB) you end up with the same gain but the deviations from flat frequency will tend to average themselves out as the outputs from the two will combine.

This is a simple case of adding and then dividing by two. How is that not averaging? Aside from the fact that it can be consistently shown with direct measurements.

Until you can prove me wrong instead of just throwing insults you have no high ground.

Herman I have 2 bass horns about. The massive one with 4-18in and and a large front loaded design. The 4-18 is 106db 1 watt 4 ohm min has a 16 ft path. My front loader is closer to the size of your front horn. But since hybrid in design its a improvement over exponential front horns for bass, can produce lower output with less colorations or distortions its more compact suffers less from time alignment issues and can be just as efficient. The front radiation on the 4-18in is not producing most of the output since its run below 50hz. Most output comes from bl horn. Which is tuned at 50hz. The front loaded bass horn 94db 6 ohm and produces 18hz with much pressure. I use SETs but also powerful amplifiers. If amplifiers designed proper has low noise if loudspeaker impedance match's than why only limited oneself to small power. There is no one way or the highway here. Many ways to skin the audio [or horn] goose.