Original L100s, what are they talking about...............?

[Wagner]

I've read this in numerous articles, this excerpt (and example) from the excellent history here, on this site:
" A number of simplifications were made in the new model. The transducer array remained the same, but the raised section of the front baffle was eliminated as were the dividing network attenuator controls."

http://www.audioheritage.org/html/profiles/jbl/l100.htm

"as were the dividing network attenuator controls" is the part I don't understand.

Every incarnation of this loudspeaker I have ever seen, or seen photographed, has HF and MF pots on the front.

So what was "eliminated"?

Was there a 3-way mechanical switch, adding or subtracting resistors from the circuit as well, on the 4310? Like an N1200?
(don't think I've ever seen the back of a 4310)

Please explain.

Thank you!

Thomas

[sperkerchef]

There were three versions of the l100. The first were the in-line with the le20-1 and it had a full range crossover. The later and more common l100's had the le25 tweeter and a different near field crossover like in the the 4311's. The later model l100's and l100a's were the same except I believe the l100A's had an updated woofer in the 123A-3 as opposed to the 123A-1. I have three pairs of l100's and think the in-line's sound the best because of the crossver and the Ed May JBL debate over the production of the l100's which also supports my opinion.

[Wagner]

Guess no one's actually reading my question.

Thomas

[Don C]

The text is not correct as written. I think that it should say that the level controls were removed from their prominent exposed location or moved to a hidden location behind the grille. It's not that big of a deal though, possibly an editing mistake.

[grumpy]

+1

Beat me to it

[Wagner]

The text is not correct as written. I think that it should say that the level controls were removed from their prominent exposed location or moved to a hidden location behind the grille. It's not that big of a deal though, possibly an editing mistake.

Thank you!

No, it wasn't a big deal; I just for the life of me could not find, or remember ever seeing, any systems (L100s) that did not have level adjusts.

And the word "simplified", along with the balance of the text, had in fact led me to believe that such an animal existed.

Just moving them to a new location on the cab did not equate with the concept of "simplification" in my mind.

Thank you much for the clarification.

Thomas

[qquickk]

There were three versions of the l100. The first were the in-line with the le20-1 and it had a full range crossover. The later and more common l100's had the le25 tweeter and a different near field crossover like in the the 4311's. The later model l100's and l100a's were the same except I believe the l100A's had an updated woofer in the 123A-3 as opposed to the 123A-1. I have three pairs of l100's and think the in-line's sound the best because of the crossver and the Ed May JBL debate over the production of the l100's which also supports my opinion.

Does anyone know the values of the original parts in crossover of the 4310 speakers? Was it just a coil and two caps?
Thanks.

[Harvey Gerst]

As I remember it, George Augspurger reworked the 4310 crossover for the L100. I don't know what he did to it, but George was responsible for the changes.

[qquickk]

As I remember it, George Augspurger reworked the 4310 crossover for the L100. I don't know what he did to it, but George was responsible for the changes.

Thanks, having fun with these. Are in 100 liter solid walnut cabinet from the era.