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Jbl l100 and 4311 imaging (or lack thereof)

Akustic said:
Yes .. but definitely less than a transmission line ..

Who was the first to come up with that long stuffing business ??
I remember that a number of speaker manufacturers were touting it for a while ..
The concept came from tuned ports .. well graduated from an open hole to tuned lengths, and then stuffing the port ..
Better than a chuffing port, but compared to Acoustic Suspension or a pair of Freid's, they still sounded like ported boxes to me.

My recollection is that Freid was manufacturing the closest thing to a real transmission line at the time and the bass lines from a pair of Freid's was delicious,
but he wasn't so good when it came to the top end .. at least that was my experience.

Transmission tuned ports ??
Click to expand...
If Arnie Nudell called them a transmission line and the police came to visit my roomate that is good enough for me, although I do understand that they do not have the Fried architecture that many of us associate with a transmission line. However by definition if the wave is altered by 45 degrees it may become a transmission line also by definition even though the structure was different.
 
Perhaps if the back wave of the woofer comes out the front baffle creating a 45 degree wavefront it will add to the front wave by the cosine of 45 degrees which may be a total output of 1.5 times of the original wave, if I have done the geometry and addition correctly.
 
backmd said:
Perhaps if the back wave of the woofer comes out the front baffle creating a 45 degree wavefront it will add to the front wave by the cosine of 45 degrees which may be a total output of 1.5 times of the original wave, if I have done the geometry and addition correctly.
Click to expand...
Sorry square root of 2 divided by 2. so 1.707 times the output.
 
backmd said:
Here is a review describing the transmission line design of the Infinity Monitor Jr. a competitor to the JBL4311 that images very well.
https://worldradiohistory.com/hd2/I...Modern-Recording-1976-04-05-OCR-Page-0060.pdf
Click to expand...

The Jr. was designed after the conversation about imaging and how to achieve it had been initiated in the high end ..
High end designers were messing with the concept and how to improve it ..Nudell was paying attention.
It took quite a number of years for mainstream speaker manufacturers to integrate imaging performance into their products.
The JBL was designed before imaging was a topic in speaker design ..

This was an era of Transmission tuned ports also .. I kind of doubt that Infinity had a patent on it .But they may have ,, Arnie Nudell was a talented creative designer ..
There were a lot of variations on the concept ..
 
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It turned out to be baffle diffraction off the wide front baffle that was preventing good imaging performance ..
That's pretty much why old speakers are wide and newer speakers are narrow ..
 
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