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View Full Version : What xover frequ. between 116A and 066?



Helmut
06-02-2007, 06:36 AM
Hello, esteemed board,

I have a few systems on the shelf that urgently want to play some music,
and with your valued help I'm planning to populate a pair of L19 cabinets.

So where would one mate a 116A woofer with a 066 tweeter? My conundrum, the two JBL systems that use the 066, have rather high crossover frequencies that would not immediately fit to the 116A (L166: 6kHz; the L212 service document says 3000kHz, but I presume that is a clerical error, the lone 4uF C2 cap looks like 6dB at 5kHz).

Somewhere Giskard mentioned that the 034, 044, and 066 are quite equivalent, and that would allow for going down to 2500Hz xover frequency, right?

So would a crossover frequency of 2500 or 3000 Hz with 12dB slope be ok?
Should I use the layout of the L19 xover for starters?
Or would there be some advantage in using 18dB design (going easy on the 066)? What's the highest one would feed to a 116A (I seem to recall that the frequency curve is a rather bumpy ride above 2500Hz on-axis).
Although, in the L16 Decade the 116A are used as a broadband, and they sound good to me.

Let me add here that my listening level is rather moderate and that the main amp for the prospective speakers would most of the time be a vintage 14W tube amp. So the power going to the 066 is generally low.

Thanks in advance for your valuable help!

4313B
06-02-2007, 06:45 AM
So would a crossover frequency of 2500 or 3000 Hz with 12dB slope be ok?Probably.
the L212 service document says 3000kHz, but I presume that is a clerical error, the lone 4uF C2 cap looks like 6dB at 5kHzI would imagine that they are referring to the acoustic crossover. I've gone over this stuff in great detail before.

Should I use the layout of the L19 xover for starters?Look at it as well as others such as the L46, L60T and 4408 crossover schematics.

It's real hit and miss doing any of this without support gear.

duaneage
06-03-2007, 08:38 PM
IF you are going to try a 18db/oct crossover for the tweeter You may need to reverse polarity on the tweeter to get better results. Mating a 12db/oct woofer crossover with an 18db/oct tweeter network may cause unusual results.

Helmut
06-05-2007, 04:40 PM
@Giskard: thanks, will have a look at the xover designs you pointed out. I understand that it would be nice to have some measurement gear, but that little project of mine does not warrant to purchase a Behringer and mic.

@duaneage: thanks, and points well taken. So I will play it safe and stick to 12dB/oct on both ends.

Will post again if all my clever plans have panned out ;-))