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IMF Transmission Line Stuffing?

MJKing said:
There is no such thing as an 1/8 wave length TL, every TL is quarter wavelength and the geometry can be used to push the tuning frequency up or down.
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http://www.questforsound.com/speakers/spkrs_buggTusselAmyGDala.htm

http://www.stereotimes.com/speak032902.shtml

Dr. Kevin Blair wrote about his 1/8 Wave length designs in Speaker Builder issue 2-1994.


For some reason I can't copy and paste the Gary Galo article that appeared in Speaker Builder issue 1-1982.
It is the Transmission Line Theory-Cardoza and Company pdf file in the link.

http://www.google.com/search?q=tran...CYOfyASdhIKIDQ&start=10&sa=N&biw=1368&bih=783
 
Every TL that is closed at one end and open at the other has a fundamental 1/4 wavelength resonance. Anybody claiming it is tuned to be 1/8 or 1/6 or 1/2 or some other fraction is reinventing basic physics. If you read any other fraction when describing a TL speaker system, immediately think "marketing" .
 
MJKing said:
Anybody claiming it is tuned to be 1/8 or 1/6 or 1/2 or some other fraction is reinventing basic physics. If you read any other fraction when describing a TL speaker system, immediately think "marketing" .
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Dr. Blair's designs are based on 1/8W for the driver Fb and 1/4W for the driver Fh. His design uses foam for the damping material.
 
JimPA said:
Ken how could the anti resonant line terminus frequencies be spherical in nature when emerging from a rectangular vent?
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The type of wave propagation is not determined by the shape of the radiator. It is determined by the relationship between the size of the radiator and the wavelength of the sound. When considering long wavelengths, all monopole radiators act like a point source, and produce spherical wavefronts. (Just think about dropping a rock into water. The shape of the rock doesn't really change the shape of the waves.)

-k
 
Roger Sanders

ken kantor said:
I tried reading this.

In all due respect, this guy does not know what the hell he is talking about. At all. His "White Paper" is drivel. I don't mean, "I disagree with the author." I mean, "He says many things that are just plain incorrect."

-k
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Ken, I could not have agree more with you on the writing of Mr. Sanders.

I was a charter subscrber of the Audio Amateur magazine in the 1970's. It inspired me to graduate from the Heath-kit/Dynaco to building from scratch. Among the early favorites are the David Hermeyer's on electrostatic speaker, Theodore Jastak's on transmission line speaker and Walter Morrey's on super low distortion signal generator. As the magazine matured, it even attracted big name authors such Nelson Pass and Erno Borbely. But the quality of writing was uneven from the early day. I did not renew my subscription when Ed Dell retired and I feel no confidence of the editorial staff.

Roger Sanders was a very hard worker. But he did not seem to understand the topics he discussed well. I am glad you find it the same way.
 
"...big name authors such Nelson Pass and Erno Borbely..." Those are "big name authors"? Hmmm. (I know the first, but not the second.) I guess that's why it's called Audio AMATEUR.... :)

Seriously, I liked Ed Dell a lot, and enjoyed Speaker Builder regularly.

-k

So, I looked up Borbely. Definitely a pro. I even own some of his designs. He seems oddly attracted to exploring every permutation and combination of amp topology, but hey, you have to keep those articles coming! But, the man has credentials and chops, and he doesn't seem inclined to make incorrect assertions about how amps work, unlike certain others....
 
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JimPA said:
I wonder why Roger Sanders received so many awards for his many designs?

http://sanderssoundsystems.com/product-reviews
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Really? You can repackage cat piss into $39 bottles of "contact cleaner" and someone in this biz will give you a rave review and an award...

People get awards for making dealers and magazines money. Nothing more, nothing less.

Besides, I never said his speakers didn't sound good. There are plenty of great speakers around whose designers wouldn't pass a high school physics class. And there are brilliant and educated designers who know exactly what they are talking about, yet can't quite apply it towards great sounding speakers. (To some, I fit that bill.)

-k

PS- Do you think that the editors and writers at audio magazines have anywhere near the credentials to judge the technology claims presented to them?
 
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ken kantor said:
Really? You can repackage cat piss into $39 bottles of "contact cleaner" and someone in this biz will give you a rave review and an award...

People get awards for making dealers and magazines money. Nothing more, nothing less.

Besides, I never said his speakers didn't sound good. There are plenty of great speakers around whose designers wouldn't pass a high school physics class. And there are brilliant and educated designers who know exactly what they are talking about, yet can't quite apply it towards great sounding speakers. (To some, I fit that bill.)

-k

PS- Do you think that the editors and writers at audio magazines have anywhere near the credentials to judge the technology claims presented to them?
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Ken even though I have post many links doesn't mean that I agree with them.

I do enjoy getting your opinion of the subject matter from the author's writings.

One scientific fact that can't be denied are some of the driver tests done in 1/4W T-line enclosures.
Gary A.Galo in 2-1986 Speaker Builder did a test of several 5" drivers.
The Kef and Audax bextrene cones that have a peak of 10db at 1500-1900hz were reduced to 5db and flattened out quite a bit.

IMHO you do respect the work of Gary A. Galo who did many of the speaker reviews that appeared in the magazine.
 
One interesting fact these links show is the weight of the various densities of foam and the tensile strength.

http://www.foamonline.com/types.php?cartID=60c3bb9c2dad8a63cb4d8c79932cefdb

http://www.foamforyou.com/Foam_Specs.htm#Open Cell Foam Specs

By comparing the specs of the various foams available the weight of the foam used by Fried is 1.2 lbs per cu.ft. being the plush soft type which is low density.


Open_Cell_Foam.htm
 
JimPA said:
Ken even though I have post many links doesn't mean that I agree with them.

I do enjoy getting your opinion of the subject matter from the author's writings.

One scientific fact that can't be denied are some of the driver tests done in 1/4W T-line enclosures.
Gary A.Galo in 2-1986 Speaker Builder did a test of several 5" drivers.
The Kef and Audax bextrene cones that have a peak of 10db at 1500-1900hz were reduced to 5db and flattened out quite a bit.

IMHO you do respect the work of Gary A. Galo who did many of the speaker reviews that appeared in the magazine.
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Hey, I was only responding to your question about awards....

I certainly know Gary Galo's name, but I know nothing about his work or theories.

-k
 
ken kantor said:
"...big name authors such Nelson Pass and Erno Borbely..." Those are "big name authors"? Hmmm. (I know the first, but not the second.) I guess that's why it's called Audio AMATEUR.... :)

Seriously, I liked Ed Dell a lot, and enjoyed Speaker Builder regularly.

-k

So, I looked up Borbely. Definitely a pro. I even own some of his designs. He seems oddly attracted to exploring every permutation and combination of amp topology, but hey, you have to keep those articles coming! But, seriously, the man has credentials and chops, and he doesn't seem inclined to make incorrect assertions about how amps work, unlike certain others....
Click to expand...

I cannot say the same about "Gary A. Galo", who was one of the reason that I stopped my Audio Amateur subscription after many years.
 
keilau said:
I cannot say the same about "Gary A. Galo", who was one of the reason that I stopped my Audio Amateur subscription after many years.
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ken kantor said:
Why is that? (As I said, I know almost nothing about his work.)

-k
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I do not have confidence on his audio judgement if one considers the AR-XA turntable to be a "top notch" turntable. in 1964, Edgar Villchur designed a low-cost ($78) belt-drive turntable with a cast aluminum 3.3 lb (1.5 kg) turntable platter suspended with a T-bar sub-chassis to reduced acoustic feedback. He used a 24-pole hysteresis-synchronous, permanent magnet Hurst AC motor propelled the platter via a precision ground rubber belt to produce very low wow and flutter. But Edgar cannot afford to put a high quality bearing on the design. As a result, the AR turntable will sound excellent for a few months, but starts deteriorating when its cheap bearing develops play. The problem was easy to detect and very audiable.

The Minneapolis area was an audio hot bed in the 1970's. When I looked for something better than the Dual 1219, I first looked at the AR because of all the noise about it. But I was pointed to the right direction by one of the most respect audio Boutique owner in Minneapolis who taught me how to distinguish the sound of the AR vs. a Thorens TD-160. I never look back since.

Anyone who has question about the importance of the turntable bearing can find the answer in early Linn Sondek LP12 product borchure.

Gary A. Galo wrote a series of AR mod articles for Audio Amateur, but never mention its fundamental bearing problem. He later became editor of the AA. The AR turntable is one, but not the only issue I took.
 
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