Model 14 crossover schematic & driver question.

[argieX]

Hi.

I recently bought a pair of Altec Model 14 tweeters and crossovers.
Now I want to pair them up with some JBL 2225H woofers.

But the crossover is strange looking, I have never seen a crossover with MF and HF attenuators, and this has a 50ohm potentiometer over the woofer coil ?

Does anybody have a schematic of this crossover or know anything about this croosover ?

Furthermore it seems to have been modified by cutting the tweeter coil, so it is only 6db instead of 12db.

And can you tell me what these drivers are ?

They are a bit corroded so in the process of removing the diaphragms I broke one connection on one of the diaphragms, but it looks repairable.

The number on the diaphragms are 391923 and 391926, are they any good ?







Regards
Kim

[boltupright]

Hi, those drivers are 902's, they are very good drivers, it will be pretty tricky to fix the diaphragm lead to where it's 100%.
If you have trouble fixing it you can get new replacements at Great Plains Audio.
I'm not shure if you could use that horn & crossover point with the JBL to good effect, I think the model 14 cossover point is 1500Hz.

[gamalot]

Hi Kim. I am not an expert here so take none of this to the bank!
Look like 902 Drivers to me with the tangerine phase plugs.
The numbers you give 391923 & 926 I believe are date codes. 923 meaning 1979 in the 23rd week and 926 being 1979 in the 26th week.
There is alot of info here and alot of very sharp individuals who may chime in.
I think the diaphram can be replaced at GPA and I would be skepticle about repairing it but many have been successfull in doing so.
The orange phase plugs are known for comming unglued but can be reglued.
Be very carefull in the cleaning so no metal shavings get down between the magnet and center cup. Use doubled over, sticky side out tape to slide in and get any debris out of there.
Best of luck with your project.

Gary

[argieX]

Hi guys, thank you for your help.

I have fixed the diaphragm, and it sounds just as good as the other one.




I think I was lucky it didn?t break closer to the voicecoil.
The soldering doesn?t look so nice on the picture, because I didn?t clean the top surface of the wire, but the two surfaces meeting each other are nice and clean, and it is a strong bond.

Let?s see if it will hold in the long run.

The diaphragms are coated very lightly with some sort of pink stuff, is this done from the factory ?

The JBL 2225?s have been put in some 110L reflex cabinets I had standing around, they are tuned to about 27hz and actually sound pretty good.

They miss a bit in the lowest frequences, but what is there sounds great.

Regards
Kim

[Carl Bill]

You could also leave off the loading caps and get regular 902 rear covers from GPA. That usually helps the sound a bit, but will lower the power handling. Just my .02.....