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stimpiew
06-03-2003, 11:05 AM
Hi, I'm going to rebuild my N65B network to the 3114 network from the 4315 monitor. Just a few questions:
-What kind of inductor is the .15mH one for the tweeter? Because there are three wires coming from it. Is it 0.075 in series and 0.075 in parallell?
-Which values should I use for a -3dB resistor for the 077 and where should I put them.
Greetings,
Wim

4313B
06-03-2003, 12:46 PM
"What kind of inductor is the .15mH one for the tweeter?"

It's an iron cored tapped autotransformer.

"Because there are three wires coming from it. Is it 0.075 in series and 0.075 in parallell?"

No, the 0.16mH in the 3114A is tapped at the -3 dB point which is roughly the 1/sqrt(2) position. Naturally it isn't quite that simple due to mutual inductance but close enough I suppose.

"-Which values should I use for a -3dB resistor for the 077 and where should I put them."

*****

The L-Pad in the schematic below is 8 ohms.

stimpiew
06-04-2003, 01:49 AM
Thanks for your answer Giskard.

boputnam
06-06-2003, 07:22 PM
I believe your model, the LE5-5, has a concave paper dome instead of the hard aluminum dome. The concave paper dome breaks up more severely than the aluminum dome.

Is this inherant for the LE5-2, as well - which predated the -5, and had the "splendiferous" Alnico motor?

4313B
06-07-2003, 10:13 AM
You're fast Bo! You got a post in while I was deleting my post :p
You downloaded the graph as well? ;)

The break-up is inherent in the old concave paper dome. The 2121 is another one that suffers from the concave paper dome. Sure looks cool, but it isn't so cool for audio. :( That's yet another reason I would do the 4345 network and 2122 in a 4343B these days ;)

boputnam
06-07-2003, 11:28 AM
Ha! Maybe TOO fast - I noticed you had edited yours (I guess before you deleted it :) ) I did see the graph, and left it for later - Doh!! :( I'd be most happy to pick-it-off if you decide to repost it! I have a growing "Giskard Library" - no kidding! Between you and Mr. Widget I will soon be quite single but have stunner sound in the home!! "Forum Widow" my wifey calls herself...

Great point about the 4343B - but getting hold of a 2122 is more difficult than a "splendiferous" 4311WX... ;-P

I "thought" I preferred the LE5-2 to, to say, the LE5-9 or higher. I thought it a bit less harsh. But the break-up in the upper-end of that LE5 plot you posted (briefly) yesterday, was disheartening. Looks too severe to address with a crossover.

Robh3606
06-07-2003, 10:01 PM
"For some reason, it appears JBL has a few brand new 2122H's.
I suppose they are left over from a 4344 overrun."

Some of the ones they sold off in the "Tent" were new. I was lucky and got a pair of them.

Rob:)