DIY N2400 Crossover Clone for JBL C36

[bob smog]

Hi all - about 10 years ago, I lucked into a curb find pair of JBL C36s. These have been my main speakers for the last decade. Recently, I noticed one speaker was playing quieter than the other. I opened things up to take a look.

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The drivers checked out OK, which led me to the N2400 crossover. The L-pads were flakey when I got these, but some contact cleaner got them working OK. Now that there are issues again, I decided to build a pair of N2400 crossover clones, rather than hack up the originals.

Speaking of originals, here's a shot of one of them. Looks like a date code of 1969. I verified that these crossovers have the 5 ohm resistors added.

More pics to follow - I have all the parts and hope to have this knocked out over the weekend.

 

[geiman]

I scratch built a pair of these for a JBL D-123--075 combination. You'll do well with your project. Mine turned out great.

 

[bob smog]

Cut out the backing boards and put on some hardware.

Wired up the pass throughs.

Added components.

One down, one to go -phew, gonna get some lunch.

 

[bob smog]

Finished the second one. This one went faster since I didn't have to figure out the lead dress.

For both, I worked off of a hookup diagram I made, which was realky helpful.

 

[bob smog]

Did a test fit - dropped right in to the existing crossover cutout.

Out of time for this week, going to get it back together next weekend.

 

[geiman]

Very nice Bob! I'll be glad to know how they sound.

 

[bob smog]

Very nice Bob! I'll be glad to know how they sound.

Yeah, me too. I have very limited time to work on these. I really hated to stop before hooking them up, but I don't want to be in a rush to put stuff back together.

I'll report back once I get them up and running.

 

[bob smog]

Got everything back together this weekend.

Must say the new crossovers were totally worth the effort. The speakers have a new level of clarity in both the highs and lows that was missing before. Not only that, but the bass response has improved along with the overall balance. Extremely pleased with the outcome. I would expect them to sound even better as the new caps break in.

Ending up costing about $60 each in parts, so $120 overall. The most expensive part was the 1.0 mH inductor 14ga. I suspect this part is responsible for the better bass response, although the new caps are probably helping too.

I'm also enjoying the new binding posts. So much easier to hook up than the old JBL pushbuttons.

Here's a few more pics from the project.

 

[audiomagnate]

Where do the 5 ohm resistors go in the circuit?