@GM
I looked at the date on JBL 2425 driver holding the Radian diaphragm, I installed it 21 years ago ( I only had a basic RTA at the time for frequency analysis ).
All my Radian 1225-8 diaphragms are from that era.
I have a single ( Altec compatible ) 1228-8 diaphragm that I've never been able to get close to a satisfactory alignment.
Here's a look-see at the raw response of the JBL/Radian driver ( among others in the jumble of traces > all on the 18Sound XT1464 ) .
It appears the 6K ( 4-5db deep ) hole I have with the Radian 1225 is maybe a common problem.
See similar measured on a 1" Plane-Wave setup ( Barry > 1audioHack over at LHF ) . This response pic is from 2011 .
- it's too bad TEF has such abysmal export graphics ( needless to say, the 5db notches seen around 6K belong to two Radian diaphragms in 2 JBL 2426 motors.
The author of the post ( at LHF ) stated that Barry was able to get rid of that notch with some extra fiddling ( which is good to know ).
🙂
BTW; I included the impedance curve of the Radian diaphragm ( which quite closes mimics the original JBL ) to show why it seems to be a loud diaphragm ( it's just over 4 ohms for a lot of the band-pass vs the Altec which is slightly above 8 ohms ) .
- Impedance curves were done by S&L's WT2 with resistor calibrations done before each new impedance run.
I looked at the date on JBL 2425 driver holding the Radian diaphragm, I installed it 21 years ago ( I only had a basic RTA at the time for frequency analysis ).
All my Radian 1225-8 diaphragms are from that era.
I have a single ( Altec compatible ) 1228-8 diaphragm that I've never been able to get close to a satisfactory alignment.
Here's a look-see at the raw response of the JBL/Radian driver ( among others in the jumble of traces > all on the 18Sound XT1464 ) .
It appears the 6K ( 4-5db deep ) hole I have with the Radian 1225 is maybe a common problem.
See similar measured on a 1" Plane-Wave setup ( Barry > 1audioHack over at LHF ) . This response pic is from 2011 .
- it's too bad TEF has such abysmal export graphics ( needless to say, the 5db notches seen around 6K belong to two Radian diaphragms in 2 JBL 2426 motors.
The author of the post ( at LHF ) stated that Barry was able to get rid of that notch with some extra fiddling ( which is good to know ).
🙂
BTW; I included the impedance curve of the Radian diaphragm ( which quite closes mimics the original JBL ) to show why it seems to be a loud diaphragm ( it's just over 4 ohms for a lot of the band-pass vs the Altec which is slightly above 8 ohms ) .
- Impedance curves were done by S&L's WT2 with resistor calibrations done before each new impedance run.
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Thanks! My experience ended in '96 right before I got online when the Altec distributor was closing out all Altec inventory due to rumors of it being bought out and to expand the B0$3 prosound market share. They had been 'pushing' Radians and with my only having a pair of regular and ultralights left, figured that I could get by with the Radians for the regulars, so was allowed to try a pair on my dual 802 WGs, but even at my 3 kHz/2nd order they sounded worse than the Symbiotik, so back they went.
Looking at the measurements, I'm at a loss as to why they sounded obviously inferior [especially to my female references] unless they were new/old stock being presented as 'improved' over the earlier junk that often had to be tweaked just to get them installed properly.
Looking at the measurements, I'm at a loss as to why they sounded obviously inferior [especially to my female references] unless they were new/old stock being presented as 'improved' over the earlier junk that often had to be tweaked just to get them installed properly.
Anyway, I ordered Eminence PSD2002, because it seemed most reasonable option Wondering now with what 15" to mate it. I am even considering Karlson.