watchnerd
Grand Contributor
I'd be curious if it could be measured in the crossover by itself using a dummy load.
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Horn Speakers - Is it me or.......
- Thread starter March Audio
- Start date
I'd be curious if it could be measured in the crossover by itself using a dummy load.
Must have been the cables they used.
Expectation bias? Why is it everyone blames it for everyone else, but won't believe it for themselves?
I am with Sal ...Must have been the cables they used.
Expectation bias? Why is it everyone blames it for everyone else, but won't believe it for themselves?
Yep, You see a horn, so you hear a horn.
That would be the first thing we'd tell others.
Must have been the cables they used.
Expectation bias? Why is it everyone blames it for everyone else, but won't believe it for themselves?
I very much admitted to that possibility several posts back.
Post 69.
Of course - if there is any in the first place. It's just a theory I've developed, I couldn't find any other explanation why even very small active speakers like the Genelec 8020 show such great dynamics.
So only those round horn designs are real horns?
You said this was not a horn?
So then Klipsch doesn't make horns?
Another point is the every design has it's weaknesses, most have minor coloration's of their own, some are insane loads that can drive normal amps into instability. Some require insane amounts of power to make a squeak and their distortion levels at normal listening db are questionable. Some like to turn into a Tesla coil impersonation if driven too hard.
You buy your ticket and take your ride.
I auditioned those JBLs. I didn’t like them, at least in the store setup, which was pretty bad.
This is not correct. A passive crossover does not add compression.
Of the components used in a passive crossover, the inductors are most problematic. They have dc resistance, and can also have hysteresis causing inductance to change as funstion of current. But this does not cause compression, because the inductance gets lower with increased current, and the dc resistance does not change significantly. Resistance is also accounted for in the design. Using a bad inductor will show up as nonlinear distortion and a level-dependent change in frequency response.
Passive crossovers can also be made with linear and flat phase, with very steep slopes. It is just that it is not so easy to design.
Main drawbacks of passive are complex and difficult to design, expensive components, impossible to do delay. Part from those issues, a passive can perform just as good as any active dsp solution.
Compression in loudspeakers is manly caused by nonlinearities in the drivers - in the motor and suspension.
All of this is quite straight-forward to measure and verify.
The reasons for using a horn in a loudspeaker has to do with efficiency and radiation pattern - at least when we limit the discussion to purely performance and technical related, solutions for esthetics and marketing is not necessarily the same.
Radiation can be fairly accurately controlled using a horn - it is possible to design for a specific pattern, you decide what kind of radiation you want. Then you design a horn to match this requirement. As frequency goes down, there will often be a problem with visual appearance and physical size, as the size of the horn mouth ends up comparable in wavelength (typical dimension around 1/2 wavelength) to the sound. So horns are typically only used for higher frequencies in commercially available speakers.
Efficiency is increased by acoustic loading of the driver. Here, it is possible to use horn solutions also for lower frequencies, if pattern control is not required. Loading a small driver with a proper horn channel can reduce distortion and increase spl capacity significantly.
What is a horn. Are there criteria that can be used, to say whether a specific design can be called a horn. In this thread, several different types and shapes of horns are shown. As I see it, all are horns. If you decide to call it a waveguide, I see that purely as some kind of marketing stunt, to avoid the bad-horn label.
Since there are so many, so different, designs and systems and solutions that incorporate some kind of horn, we can not say something general about the sound of a horn. Because they are so very different. What we can say something about, is how a specific radiation pattern sounds.
Comparing against trad small hifi-speaker with small direct radiators, some typical trends arise. Because all those small dome tweeters and small midranges tend to have a quite similar pattern, while horn designs typically have chosen a more controlled pattern, which gives some inherent differences in experienced sound character. The trad-hifi sounds softer, smoother, less dynamic - and they all tend to sound more similar than different. Comparing directly to a speaker with controlled directivity can be a real ear-opener - the frequency response measures the same, but the sound is very different.
And it is correct that all other speakers are toys. But the gap is narrowing, today we have small drivers with much larger spl capacity, we have powerful amplifiers that are nearly perfect, we have improved knowledge and technology for design.
Radiation can be fairly accurately controlled using a horn - it is possible to design for a specific pattern, you decide what kind of radiation you want. Then you design a horn to match this requirement. As frequency goes down, there will often be a problem with visual appearance and physical size, as the size of the horn mouth ends up comparable in wavelength (typical dimension around 1/2 wavelength) to the sound. So horns are typically only used for higher frequencies in commercially available speakers.
Efficiency is increased by acoustic loading of the driver. Here, it is possible to use horn solutions also for lower frequencies, if pattern control is not required. Loading a small driver with a proper horn channel can reduce distortion and increase spl capacity significantly.
What is a horn. Are there criteria that can be used, to say whether a specific design can be called a horn. In this thread, several different types and shapes of horns are shown. As I see it, all are horns. If you decide to call it a waveguide, I see that purely as some kind of marketing stunt, to avoid the bad-horn label.
Since there are so many, so different, designs and systems and solutions that incorporate some kind of horn, we can not say something general about the sound of a horn. Because they are so very different. What we can say something about, is how a specific radiation pattern sounds.
Comparing against trad small hifi-speaker with small direct radiators, some typical trends arise. Because all those small dome tweeters and small midranges tend to have a quite similar pattern, while horn designs typically have chosen a more controlled pattern, which gives some inherent differences in experienced sound character. The trad-hifi sounds softer, smoother, less dynamic - and they all tend to sound more similar than different. Comparing directly to a speaker with controlled directivity can be a real ear-opener - the frequency response measures the same, but the sound is very different.
And it is correct that all other speakers are toys. But the gap is narrowing, today we have small drivers with much larger spl capacity, we have powerful amplifiers that are nearly perfect, we have improved knowledge and technology for design.
watchnerd
Grand Contributor
It's @LTig 's idea, not mine.
I'd glad to hear it's nothing to worry about.
I'd always experienced / read about compression as a driver issue, either short term (excursion, driver break up) or long term (thermal compression over time if run close to max power handling for long period).
I'm not seeing compression here (not horns, passive crossover). The top level is, I think, representative of the loudest single tones I'll generate in music, higher SPL levels are (in my opinion) accomplished by combinations of tones...
Two tones add 6dB, four tones add anotther 6dB, that gets me to say 105dB in room, which I see on the meter regularly. 8 tones add another 6, and 16 tones another 6dB, making 117dB peak, which I might be able to generate playing a pipe organ.
As for distortion, at these levels, marginal with the lowest value of THD at the highest SPL tested.
The green line is the THD reported for the lowest SPL, but it's all ambient noise, not harmonics.
So... I don't feel I'm lacking much not having a horn in the house.
PS: I like to imagine the 15x48" panels are like the mouth of a 15x48" horn. That helps me to feel better about it, too.
Proof of concept:
113.6dB peak SPL... No single tone registering over about 95dB, most tone peaks at or below 90dB.
Track 1 - Rutter Requiem - Organ and Voices
PS: Nothing maxed out here, there's more where that came from. I just don't want to break anything...
PPS: It was at least a little beyond "loud enough".
---
Backing off to a more comfortably loud level, continuing with the CD:
Preamp Volume 121 of 151
DAC unattenuated
Using correction, with a basic signal attenuation of 6dB to accomodate any boost it might (but really doesn't) throw in (well, maybe 2 dB in some places)
Room Peak 106.5dB
LZeq 83.7 - roughly "reference" level
Amplifier heat sinks 122 and 126F in an 82F room
Claimed 700W @ 4Ohms available, not all used. Loud takes power.
Tone levels mostly below 80dB
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Amen on that. That is the number one reason the term "wave guide" have become so popular over the last couple decades. All the cupped hands nonsense that has been repeated since the acoustic suspension revolt of the 60s. Could people not hear what they gave away for a few hz of bass? Paul Klipsch used to walk around with a pin on his jacket that said BULLSHIT. LOL
Unfair judgement.
watchnerd
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What is a waveguide? There is a distinct difference...
That has always been my understanding from the 'horses mouth'.
I know, the quote form the original post from LTig was lost when I just quoted from your reply.
thanks for the link!
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This is a very good white paper.
If you stick with Geddes' definition then only an OS waveguide is a real waveguide (and a round one to it). Any other implementation would not qualify (including JBL PT waveguides, or the M2 one)
If you go with the more general distinction of directivity-focused vs loading-focused then a conical horn is definitely a waveguide (it is also pretty close to an OS waveguide if you add rounding at the throat, and that is exactly what peavy did with the quadratic waveguide design), while being the most simplistic and ancient horn in existence.
There is no clear cut with these things, and one should also consider that a direct radiating driver in a baffle is simply a 180° conical horn (with lots of discontinuities at the throat and mouth). This is also a very inefficient waveguide most of the time, due to the narrow baffle, and the 2Pi vs 4Pi questions (baffle step, etc.) are a direct consequence of this.
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