JBL 4333B Studio Monitors Upgraded with No-Rot 2236H.

[@oturgator]

Good idea with the 2236H selection but aren’t they 8ohms? I thought the cross-overs for these are tuned for 16ohm components.

[@edgewound]

Yes, they are 8 ohms. The JBL 4333B system crossovers are designed for 8 ohm. Thanks for your question!

[@Maxxzinno]

Hi, I have 4331 with 4503-1WX cabinet. It has a 3131 crossover. It has a hole for a 2405 tweeter which is capped. I want to add the 2405 tweeters. It also has only one L-Pad. Do you have a schematic of what components I need to add to the horn and tweeter while retaining the 3131 crossover. Thx

[@edgewound]

There are several different ways to go about incorporating the 2405...and each one will be subjective to your ears. One complete solution is to build a three-way crossover based in the L300/4333. Schematics are found all over the internet. Some like the Nelson Pass L300 network design. You could also just add a 12-18dB/octave high pass filter at about 10Khz for the 2405 with an L-pad for level control. The simplest...and cheapest... solution is to put a 1uf cap in series...6dB/oct@~20,000Hz or 1.5uF@15,000Hz... with the 2405 and see how you like it. Keeps it out of the circuit for the midrange driver(2420/2421/LE85) using it's natural rolloff, while providing plenty of low frequency or DC protection. Use a good capacitor like a Solen Fast Cap 400volt. My go-to for best performance value.

[@Maxxzinno]

@@edgewound hi so I ended up turning the 3131 into a 3133. I followed the JBL schematic. Most of the components were the same. I did have to remove a 5ohm 10w resistor and 1uF cap in series with the horn positive it was not in the 3133 schematic. Then, I added the components from the 3133 crossover. I would have used the Nelson Pass modded schematic but i wanted to hear them stock first

[@edgewound]

@@Maxxzinno nice! Well done.

[@Maxxzinno]

@@edgewound kzbin.info/www/bejne/gXXSfKduj5WWerMsi=Ynn28Qjg4U4jTdDF

[@Maxxzinno]

@@edgewound kzbin.info/www/bejne/gXXSfKduj5WWerMsi=Eg8FpLq5fezJwM6D

[@angelsanchezferia9705]

Do you know the size of the reflex? Thanks

[@edgewound]

4" diameter x 4 1/2" long