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quindecima
04-05-2016, 10:19 AM
Whats the sonic difference between these horns in home use?

ivica
04-05-2016, 10:34 AM
Whats the sonic difference between these horns in home use?

HI
I would expect that 2311 has to be applied with 2308 lemses.
If used up tp 10kHz, I would not expect large sonic differences using from 800Hz and up.
May be some CD network compensation would be needed with 2385 horn as can be seen from its data.
Regards
Ivica

Horn Fanatic
04-05-2016, 10:49 AM
HI
I would expect that 2311 has to be applied with 2308 lemses.
If used up tp 10kHz, I would not expect large sonic differences using from 800Hz and up.
May be some CD network compensation would be needed with 2385 horn as can be seen from its data.
Regards
Ivica

Technically, the 2311 as short as it is would be considered less a horn, than a discontinuity. An acoustic lens by it's very nature attenuates high frequency.
It's why if one prefers to hear very high frequency using an acoustic lens, a super tweeter would be in order. When the acoustic lens was implemented the dynamic range of recorded music
wasn't what it is today much less 40 years ago. Consider the 375 driver, which began to tank at 10K. If what I have read about the Hartsfield is correct, JBL introduced the 075 to give the
Hartsfield a high frequency boost when the dynamic range of recorded music improved.


BTW - The engineers at JBL did not invent the ring radiator. I believe that honor is bestowed on Stanley Stokes with his U.S. patent 1,845,768 filed in 1929. Then followed up by
David Blattner with his U.S. patent 2,058,208 filed in 1935. One feature of note regarding the Stokes design, is the phase plug. It bears a striking resemblance to the phase plug
used on the 2408 tweeter. Whereas the phase plug in Blattner's design, as long as it is, is more bullet like.

The acoustic lens is a bi-product of the devices Winston Kock developed for his microwave research.

HF

ivica
04-05-2016, 11:12 AM
Technically, the 2311 as short as it is would be considered less a horn, than a discontinuity. An acoustic lens by it's very nature attenuates high frequency.
It's why if one prefers to hear very high frequency using an acoustic lens, a super tweeter would be in order. When the acoustic lens was implemented the dynamic range of recorded music
wasn't what it is today. Consider the 375 driver, which began to tank at 10K. If what I have read about the Hartsfield is correct, JBL introduced the 075 to give the
Hartsfield a high frequency boost when the dynamic range of recorded music improved.


BTW - The engineers at JBL did not invent the ring radiator. I believe that honor is bestowed on Stanley Stokes with U.S. patent number 1,845,768 filed in 1929. Then followed up by
David Blattner with U.S. patent number 2,058,208 filed in 1935.

The acoustic lens is a bi-product of the devices Winston Kock developed for his microwave research.

HF
Hi,

Do not forget about 7cm length of 2440/41/45/46/50 internal horn, so about 18cm of the total horn length.Jbl apply 2311 over say 1200Hz, but my experience with the home listening soumd levels I prefer 2441&2311&2308 then 2420&2312&2308, using about over 800Hz network.
And as it is used with 2235 bass driver, a large amout of drver sensitivity is applied.
If talking about the 2308 acoustic lenses, its influences on the UHF frequency is pronounced over 15-16lkHZ, so for the frequency up to 10kHz, such inflence is minor, but as a kind of widening device in the sound dispersion, with the mentioned driver&horn combo would produce almost flat driver response up to 10kHz.
Regards
Ivica

quindecima
04-05-2016, 12:35 PM
I contemplated the 2385 because the 2311 is hard to come by and I assume it could be used in place of it without much difference.