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JBLPRO
05-27-2015, 03:35 PM
Just finished making a CC crossover for my 4355 monitors that I just recently completed. I would like to do some testing prior to installing them and connecting to amplifier etc. Has anyone have ideas on a few tests that I could perform to make sure I am all wired correctly. I used the Giskard/Timbers design seen here on the forum. I have the LPADS connected as well. My main concern is what impedance I should get at the input to the crossover. At present it reads .25 ohms which i assume is not the reading I should be getting. Any help would be greatly appreciated.

mk

martin2395
05-27-2015, 03:53 PM
I can measure the impedance of mine, but I have no clue whether it's relevant or not.

Ah well, I will give them ago tomorrow - they are all cabled with speakONs so I can quickly unplug 'em.

JBLPRO
05-27-2015, 04:28 PM
I can measure the impedance of mine, but I have no clue whether it's relevant or not.

Ah well, I will give them ago tomorrow - they are all cabled with speakONs so I can quickly unplug 'em.


I will add 2 x 8 ohm and 16 ohm dummy loads to the 3 speaker cable terminations to simulate more of a real world test.

mk

grumpy
05-27-2015, 07:06 PM
1/4 ohm is essentially a dead short. Perhaps you have a large inductor wired across the terminals?

JBLPRO
05-27-2015, 10:16 PM
1/4 ohm is essentially a dead short. Perhaps you have a large inductor wired across the terminals?

Well after checking my wiring I found a mistake in the 2405 HI section. I had wired the + from the amp input side to the + output of the 3.6 uf cap pair which is after the 2.0 pair and .16mmH coil. It should have been wired to the input + side of the 2.0uf cap pair which is the start of the circuit. This mis-wiring caused a short to ground thus the 1/4 ohm reading at the crossover input. The reading I get now with the 2202, 2441 and 2405 connected is 6.29 ohms. That's better :) I apologize for the premature post and appreciate the responses. A good lesson learned. Check circuit thoroughly before connecting to amplifiers and drivers. And before posting to forum :)

Don C
05-28-2015, 07:10 AM
When building a crossover, I think that you should have a function generator available to check the voltage drives. These are not expensive.

martin2395
05-28-2015, 11:03 AM
Where did 4313B's post go?

JBLPRO
05-28-2015, 02:08 PM
When building a crossover, I think that you should have a function generator available to check the voltage drives. These are not expensive.

I AGREE 100%. I do have one and that is my next step in testing. Just needed to get beyond that short I had in the circuit. Thanks.

mk