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John Curl's Blowtorch preamplifier part II
John Curl's Blowtorch preamplifier part II
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Old 6th November 2012, 07:01 PM   #29001
Kindhornman is offline Kindhornman  United States
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John Curl's Blowtorch preamplifier part II
jneutron,
The issues we are discussing in horn design are problematic to say the least. What drives the designs are the horn cutoff frequency and the flare rate that is chosen to support that cutoff frequency. Every thing else is incidental to those two factors in most horn design. While that is the case we can of course attempt to eliminate or reduce any abrupt shape changes along the path from the initial horn throat to the final flare opening. Not creating an older radial horn lens discontinuity at the intersection of the initial throat expansion and the attached flare would be the most significant area that can be improved and that is the basis of what the oblate spheroid designs are obvious improvements in. Any waveguide is a combination of compromises as with any direct radiator. We just have to chose our compromises carefully and attempt to cause the least harm.
 
Old 6th November 2012, 07:01 PM   #29002
john curl is offline john curl  United States
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I swear! People can complicate audio design, just to hear themselves talk. Horn throat distortion is real. It can be VERY critical, although JBL and others have attempted to minimize it with better horn drivers and faster flare (for the actual working range) throats in RECENT years. I must say that JBL did NOT appreciate my input, 40 years ago on the same subject. Now you would think that they improved things, just because they could. '-)
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Old 6th November 2012, 07:09 PM   #29003
Wavebourn is offline Wavebourn  United States
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John Curl's Blowtorch preamplifier part II
I am looking at my arrays now thinking: "What throat distortions are they talking about?"
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Old 6th November 2012, 07:28 PM   #29004
john curl is offline john curl  United States
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Please don't confuse the issue, Wavebourn. That is WHY we went to line arrays, 40 years ago, and retired as many horns as we could.
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Old 6th November 2012, 07:32 PM   #29005
jneutron is offline jneutron  United States
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Quote:
Originally Posted by john curl View Post
I swear! People can complicate audio design, just to hear themselves talk. Horn throat distortion is real. It can be VERY critical, although JBL and others have attempted to minimize it with better horn drivers and faster flare (for the actual working range) throats in RECENT years. I must say that JBL did NOT appreciate my input, 40 years ago on the same subject. Now you would think that they improved things, just because they could. '-)
I am not quite sure why you posted that. We are discussing the technical nature of distortion mechanisms in the throat and compression chamber. Do you have any input in that regard?

jn
 
Old 6th November 2012, 07:33 PM   #29006
Wavebourn is offline Wavebourn  United States
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John Curl's Blowtorch preamplifier part II
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Please don't confuse the issue, Wavebourn. That is WHY we went to line arrays, 40 years ago, and retired as many horns as we could.
I don't confuse. I totally understand why I use line arrays, but never horns.

Well, almost. My concrete waveguide under the floor can be viewed as a short horn.
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Nothing in the universe is perfect. The ideal things are the ones that are most optimal. Optimization criteria, what matters. When I hear "No Compromise Design", I want to take a sledgehammer and test how impact-proof it is.
 
Old 6th November 2012, 07:33 PM   #29007
jneutron is offline jneutron  United States
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Originally Posted by Wavebourn View Post
I am looking at my arrays now thinking: "What throat distortions are they talking about?"
It's all about surface area..

jn
 
Old 6th November 2012, 07:37 PM   #29008
Wavebourn is offline Wavebourn  United States
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John Curl's Blowtorch preamplifier part II
Quote:
Originally Posted by jneutron View Post
It's all about surface area..
Exactly! Big surface area, tiny displacements, high sensitivity, low distortions.

Well, also tall. Like that stick with 64 capsules 12 mm each I use as an experimental tweeter in the central channel in my HT.
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Nothing in the universe is perfect. The ideal things are the ones that are most optimal. Optimization criteria, what matters. When I hear "No Compromise Design", I want to take a sledgehammer and test how impact-proof it is.
 
Old 6th November 2012, 08:28 PM   #29009
cliffforrest is offline cliffforrest  United Kingdom
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John Curl's Blowtorch preamplifier part II
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Mickey only makes guest appearances to conduct the Dukas
A Fantasie lost on many ....
 
Old 6th November 2012, 08:45 PM   #29010
fas42 is offline fas42  Australia
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Nothing is perfect, Frank.
That's what my main agenda is ... I believe, very strongly, because I've experienced it many times, that the illusion can be maintained no matter how close one gets to the speaker drivers. It's all a matter of degree, the system has to be absolutely correctly aligned for this to happen, requires extreme fussiness about every detail, but when you get it right there's no questioning about the effect: the ear/brain is happy to be fooled into thinking that the speakers aren't in the room, no matter what. And all the adjectives that people throw around about impressive sound all make sense ...

Frank
 

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