136 A vs. LE15 A

[Triumph Don]

What are the diffs between the 136 A and the LE15 as far as build and sonics?

[Mr. Widget]

The 136A uses a heavier cone due to the addition of the mass ring. It has a smaller magnet that is focused on a shorter gap.

The LE15A has a short voice coil in a long gap (underhung) and the 136A has a long coil in a short gap (overhung)

As for performance the LE15A is slightly more efficient and has slightly better transient response, but these come at a loss of very LF response.

The 136A is the consumer model number for the JBL Pro 2231A. The 2235H is the evolutionary descendant of it and is slightly better in most respects.

[Alex Lancaster]

The LE15A, 2215A in pro, and the ferrite H's are IMHO, dinosaurs, the slightly better efficiency is meaningless, as they were measured from 100-500Hz, hardly LF, also they handle less power; Still, some people like them.

Alex.

[slxrti]

I had a opportunity to try the 2235, 136 and le15a., The Le15 and 136a produced less bass and the quality wasn't as natual sounding (compared to the 2235).

I used a ~6 cubic foot enclosure ( tune each driver to 30 Hz.) and a electronic crossover with gain adjustments to optimize each driver.

The 2235 won everytime, I guess that's why they don't make the other two.
The LE15 was the worst of the lot.

Slxrti

[Ian Mackenzie]

Its interested that the LE15A had the reputation at the time as the ultimate bass driver.

Perhaps JBL were playing on the marketing legacy of the LE series to introduce the technically superior 124/136.

I still recall installing the 2231A woofers (some 23 years ago) in my earlier attempt of the 4343, and is sounded subjectively more accurate than similar size boxes housing the LE15A.

We later bought more shares in JBL with a new set of 2235H's. These seemed to produce higher output under stress, (with a larger Xmax) and appeared more robust against the devastating Phase Linear 700B.

One things for sure, the 2231A and latter 2235H just wipe the floor with anything else I've heard in a 15 inch driver.

Ian:smthsail:

[4313B]

Hello slxrti,

I did the exact same thing with a 5.0 cubic foot enclosure tuned to 30 Hz and arrived at the same conclusion.

I also tuned each driver to it's optimum tuning frequency in that volume and again came to the same conclusion. I have to say that the higher recommended 36-38 Hz tuning frequency for the LE15A improved it's LF a bit. The two tuning frequencies JBL recommended for the 136/2231 were 26 Hz and 32 Hz. Neither of those tunings could assist the 136/2231 in an attempt to outperform the 2235.

The C8R2231 cone kit no longer exists so the 136/2231 is now reconed with the C8R2235 kit.

[slxrti]

I'm glad to know that others shared my conclusions.

I also found that my room played a important role regarding
Fs. I made several tube for turning the port, in my situation they had little effect (unless I used very long or short tube).

With the 136A I should have had a step response with deep bass extension. I thought I could then used the RANE to set a low crossover freq (before the step) and blend it with my 2123's.
It looked nice on paper, but the 2235 still blew it away.

By the way, a waldom cone on a 2235 sounds very nice. Not original but equal or better in performance.
slxrti

[JuniorJBL]

Originally posted by Giskard
Hello slxrti,

I did the exact same thing with a 5.0 cubic foot enclosure tuned to 30 Hz and arrived at the same conclusion.

I also tuned each driver to it's optimum tuning frequency in that volume and again came to the same conclusion. I have to say that the higher recommended 36-38 Hz tuning frequency for the LE15A improved it's LF a bit. The two tuning frequencies JBL recommended for the 136/2231 were 26 Hz and 32 Hz. Neither of those tunings could assist the 136/2231 in an attempt to outperform the 2235.

The C8R2231 cone kit no longer exists so the 136/2231 is now reconed with the C8R2235 kit.

Howdy!
I just got back from SLC with a pair of 136a's. So I did a search here and found this thread. All they need is a new surround. Would they be good for some rears for HT? What kind of power do they handle? Can they work good in about a 3 CU FT box?
I also have some le5-12's and some newer TI's out of a control 5 speaker. Any ideas?
Hey Bo I will post some pics of the old 4301b's soon.
Thanks Guys
Shane