How to use JBL K-120

[Dr.db]

Hey folks,

I own a NOS pair of JBL K-120 Alnico 12inch Woofers....

Now I`m wondering how they work the best.
So far I`ve read they shall be driven without lowbass etc.. but can be driven fairly loud with highpass.
They will run together with 2441 Drivers and 15inch subwoofer....

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So what would be the best frequency-range for these woofers ?
Where should I put the highpass-filter !? 100hz @ 12db, 200hz @ 6db etc...

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What enclosure is best ? 30liter sealed!?

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What kind of voicecoil do they use ? Do they really handle 100watts continous ?


Thanks a lot and have nice christmasdays!!!

Olaf

[Dr.db]

Has really none of you a clue ?

[macaroonie]

As a first step why don't you have a look at what the driver will do without filtering.
Download WIN ISD from here : http://www.linearteam.dk/ , the parameters for the D K and E 120 are in the applicaqtion. That driver does not do much below 80 anyway so a main - sub turnover at 100 - 120 will be easy to do. Go much above that and you will start to ' hear ' the sub.

[Dr.db]

Hi,


there will be a JBL 2235h in each speaker, so there shouldn`t be a problem with "hearing" a subwoofer.
I may did not mention this right...

I do not believe WIN ISD is a proper simulation programm, I allready had some strange output from this Data which did not compare to reality at all!
Some Cerwin Vega 18inch`s where supposed to work in 1,5 cubic feet etc...

[macaroonie]

Hi,


there will be a JBL 2235h in each speaker, so there shouldn`t be a problem with "hearing" a subwoofer.
I may did not mention this right...

I do not believe WIN ISD is a proper simulation programm, I allready had some strange output from this Data which did not compare to reality at all!
Some Cerwin Vega 18inch`s where supposed to work in 1,5 cubic feet etc...

Ah ! Well in that case ramp it up to 250 -300 to take the excursion out of the 120 and go from there. Under those circumstances you can use a pretty small ' dog box ' for the 120 .

I hear you about WIN sometimes it seems a tad optimistic as far as how small enclosures can be. As I recall it suggests 19 litres for good alignment for a 2206. That has to be wonk

[JeffW]

As I recall it suggests 19 litres for good alignment for a 2206. That has to be wonk

I think it was 16!

[jcrobso]

Here is the product info for the K series.
For a mid range speaker a sealed box would be good, I have also included T-S info.
This speaker was usually used in open back guitar amps, that is where one mine is.
How low you can use depends on how big the box is.;)
Have fun lets us know how it turns out!:applaud: