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View Full Version : Strange 2231H - Please Help Verify



wlk
03-31-2008, 08:26 PM
I recently aquired a very strange blown 15 inch JBL that has a JBL factory label that says "2231H" " 8 ohm". The frames is a light grey, textured like the paint on a 2420 HF driver and the frame has a ferrite magnet. The blown cone kit was factory installed and had a foam surround. The cone is a bit heavier and stiffer than current 2235H kits. The frame and magnet are the same size as an early model 2225H that I have but the paint on the early 2225H is the same color grey but much smoother.
Did JBL ever make a 2231H with a ferrite magnet or has the label been changed?

Robh3606
03-31-2008, 09:28 PM
Yes they did. If I can I will hunt down the photo's of the one I had.

Rob:)

wlk
03-31-2008, 10:37 PM
Rob

Thanks for the help. My 2231H looks exactly like yours. I have never seen a ferrite 2231H before.
Does anyone know when they were made?
Does anyone know if the grey ferrite 2231H and the grey 2225H are the same frames? The magnet and frame size are the same and the gap is the same.
I was planning on having the 2231H and 2225H frames reconed with new JBL 2235H cone kits. Would they make a matched pair?

Mr. Widget
04-01-2008, 12:26 AM
Does anyone know when they were made?
Does anyone know if the grey ferrite 2231H and the grey 2225H are the same frames? The magnet and frame size are the same and the gap is the same.
I was planning on having the 2231H and 2225H frames reconed with new JBL 2235H cone kits. Would they make a matched pair?The 2231H was made at the very beginning of the transfer over to ferrite from alnico. (1979ish) Others could be more specific.

Yes your 2231H frame is identical to a 2235H and a 2225H. If you put a fresh pair of 2235Hs in those two frames you will have an excellent pair of 2235H woofers.


Widget

wlk
04-01-2008, 08:51 AM
Rob & Wiget

Thanks for the excellent information.

Regards
WLK

subwoof
04-01-2008, 12:16 PM
Rright after the big rollout of the 4331,33,43 the whole magnet episode happened and the *first* components to be changed were the 15" woofers and the monitors became the "A" version.

A few monitors then had the 8's or 10's and/or compression drivers changed and became the "B" version.


It really was nuts then - you just didn't know what color / magnet / model # you were getting sometimes.

The cone assembly on the 2231A and 2231H are identical ( I have one of each in my demo box ) and they were improved slightly and became the 2235 because the coil is a tiny bit longer.

sub

wlk
04-06-2008, 05:57 PM
Subwoof
Thanks for the excellent additional information.
Regards
WLK