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View Full Version : 136A recone ,,,The truth about kit 2235 C8R2235



andychris
11-07-2010, 09:55 PM
Hello

I need to recone my 136A on my L300. I know the only kit is C8R2235. But some say that this kit not really go with 136A. They say that you can't play as loud as original 136A.

So I would like to get informations by those who has installed a C8R2235 on their 136A. Have you notified a diffrence ? It's true that the C8R2235 has a longer coil, but is it really a probleme when playing loud ?


Thanx for your answer

Rolf
11-08-2010, 10:34 AM
No problem using the 2235 kit on the 136A (2231A in the pro version) I have done this with my former 4333A's. Differences (if any) must be that they have a little more low end with the 2235 kit. Therefore: an improvement.


Hello

I need to recone my 136A on my L300. I know the only kit is C8R2235. But some say that this kit not really go with 136A. They say that you can't play as loud as original 136A.

So I would like to get informations by those who has installed a C8R2235 on their 136A. Have you notified a diffrence ? It's true that the C8R2235 has a longer coil, but is it really a probleme when playing loud ?


Thanx for your answer

ratitifb
11-08-2010, 11:59 AM
Differences (if any) must be that they have a little more low end with the 2235 kit. in addition they probably have a lowest power handling due to alnico magnet behavior vs T (actually at very high levels ...)

andychris
11-08-2010, 10:09 PM
Thanx for your interest,,,,so every things seem to be fine if I recone my 136A with C8R2235...........

ratitifb
11-08-2010, 10:50 PM
Thanx for your interest,,,,so every things seem to be fine if I recone my 136A with C8R2235...........:yes: according to JBL reconing policy and all technical knowledge i have learnt from this forum

Your 136A should be improved in terms of distortion

:blah:

From http://www.audioheritage.org/vbulletin/showthread.php?5144-136a-2231a-2235h

The biggest differences between the 2235 and 2231/136a was the introduction of a progressive suspension and high power voice coil. The progressive suspension was developed to deal with the issue of dynamic offset. At higher output levels, coil motion is no longer centered at the vertical midpoint of the coil gap but can be centered at some point outside of the gap. This greatly increases distortion. The progressive suspension acts to counteract this phenomenon and keep the coil centered. Power handling was increased with these suspension changes and the change to a kapton coil former. The result was that the later 2235 had twice the power handling of its predecessor.

From http://www.audioheritage.org/vbulletin/showthread.php?5386-2231A-or-2235H-in-4333B

The difference in resonance of a 2231 vs. a 2235 is not because of the mass... they have pretty much identical moving mass. It's because of the "softer" spider (in reconer's parlance, it's a 'B' stiffness, on a scale of 'A being softest and 'E' being stiffest) opposed to that of the 2235 (which uses a "C" stiffness spider).

With the longer voice coil and more "controlled" suspension, the 2235 definitely has the edge in distortion and output capacity on the bottom end, with about the same frequency response in its upper range as the 2231. Definitely an upgrade...

From http://www.audioheritage.org/vbulletin/showthread.php?2927-Getting-a-2235-from-other-baskets

The D130 is an Alnico driver, however it is possible to recone this and other compatible Alnico drivers (such as the 2231) into a 2235. The biggest difference in the 2235 is increased power handling, lower distortion and use of a progressive suspension to address the issue of dynamic offset. You will get most of these benefits, but not all ;) , in reconing a compatible Alnico chasis with a 2235 recone kit.

It is not possible to match the power handling of the ferrite version since you will partially demagnetize an Alnico motor before you reach the operational limits of the 2235 cone/coil assembly. The Alnico motors also have marginally higher levels of 2nd order harmonic distortion.

andychris
11-09-2010, 11:05 AM
Thanx my dear french man,,,,,,,everything is complicated when a genuine part is no more available................