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molecularman
04-23-2005, 04:17 PM
Question: I have a couple of 3110 crossovers that a friend let me borrow, and I wanted to copy them. My question regards replacing the tapped inductor with two indutors. I use the lowest setting on the switch and measured the inductance across the hf terminals and got 0.5mH. The second position gave me 1 mH and the third gives 1.5mh. The total inductance per the schematic is 2.14mH. Could I used two inductors: one 0.5mH and the other 1.64mH and exclude the tapped inductor and the 80 ohm resistor that is also in series?

Report: I had a bad sounding (farting during fugel horn solo) 2441 and bought a pair of cannon sound replacement diaphragms (18ohm). I replaced the diaph (burnt smell and a little crispy) in the bad 2441 and can not tell the difference between the new and original JBL diaphragm in the other driver. I have not measured the sound with any frequency response measuring device but to my ears there appears to be no difference at normal listening levels.

Shane From Maine (but currently in CT)

Guido
04-23-2005, 04:28 PM
Report: I had a bad sounding (farting during fugel horn solo) 2441 and bought a pair of cannon sound replacement diaphragms (18ohm). I replaced the diaph (burnt smell and a little crispy) in the bad 2441 and can not tell the difference between the new and original JBL diaphragm in the other driver. I have not measured the sound with any frequency response measuring device but to my ears there appears to be no difference at normal listening levels.
Shane From Maine (but currently in CT)

The 2441 dia is aluminium whereas the cannons are titanium. The difference is noticable. Check different music material and listen longer to them.
I don't say the cannons are bad but the sound is different.

4313B
04-24-2005, 06:11 AM
Could I used two inductors: one 0.5mH and the other 1.64mH and exclude the tapped inductor and the 80 ohm resistor that is also in series?No.

Here's your equivalent circuit:

Inductor is a Jantzen 15 gauge air core with a DCR of 0.52 ohms.

Use a 16 ohm L-Pad behind the resistors and in front of the driver.

molecularman
04-24-2005, 07:47 AM
I will give this a try and some more listening to the new diaphragm.:applaud:
Shane

4313B
04-24-2005, 07:51 AM
After you determine if it sounds like you want it to, beef up the power capacity of the resistors - use something like a gang of four 10 watters for the 5.6 ohm value. Something like that - you can figure it out easy enough.