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nfbertone
07-31-2012, 10:21 AM
Hallo everybody. I want to build a passive crossover between my JBL 2440 and my JBL 077. I dont want to use any L-Pad!I found a passive crossover (www) : 1,0uF seriel ; 0,16mh parallel ; 1,5 uF seriel after this the L-Pad 8Ohm.... an than a 20 Ohm-10W parallel to the JBL 077.Can I build the crossover without the L-Pad? Drawbacks? when I did not use the L-Pad? Has anybody experiences? Or an idea to build a other crossover? I think 8kz - 10kz is perfekt .Thanks a lot, Nobby

hjames
07-31-2012, 11:09 AM
Hallo everybody. I want to build a passive crossover between my JBL 2440 and my JBL 077. I dont want to use any L-Pad!I found a passive crossover (www) : 1,0uF seriel ; 0,16mh parallel ; 1,5 uF seriel after this the L-Pad 8Ohm.... an than a 20 Ohm-10W parallel to the JBL 077.Can I build the crossover without the L-Pad? Drawbacks? when I did not use the L-Pad? Has anybody experiences? Or an idea to build a other crossover? I think 8kz - 10kz is perfekt .Thanks a lot, Nobby

Didn't you post this same comment once already.
It should be in DIY I'd imagine.

ivica
07-31-2012, 01:35 PM
Hallo everybody. I want to build a passive crossover between my JBL 2440 and my JBL 077. I dont want to use any L-Pad!I found a passive crossover (www) : 1,0uF seriel ; 0,16mh parallel ; 1,5 uF seriel after this the L-Pad 8Ohm.... an than a 20 Ohm-10W parallel to the JBL 077.Can I build the crossover without the L-Pad? Drawbacks? when I did not use the L-Pad? Has anybody experiences? Or an idea to build a other crossover? I think 8kz - 10kz is perfekt .Thanks a lot, Nobby
I think it would be difficult to adjust 2440 with appropriated horn and 2405 efficiency without resistors network or L-pads

Mike F
07-31-2012, 01:53 PM
I think it would be difficult to adjust 2440 with appropriated horn and 2405 efficiency without resistors network or L-pads

He can always Bi/Tri amp.

grumpy
07-31-2012, 02:24 PM
Nothing was said about not using resistor networks, that I noticed... :)

Just use the same resistor values that would be in effect for the L-pad
at an appropriate static setting.

nfbertone
08-03-2012, 12:04 AM
Nothing was said about not using resistor networks, that I noticed... :)Just use the same resistor values that would be in effect for the L-padat an appropriate static setting.Thank for answer! O.K. first I i will test it without any resistor to the mid-high horn. And than with differnet fixed resistors... At the moment I use one Cap 1,8uF seriel to the 077. I will test the other version...without any L-Pad, I hope the crossover from horn to the 077 will be better fit....I will told you....best regards from Germany!!

ivica
08-03-2012, 06:17 AM
He can always Bi/Tri amp.
Yes, but as it has been said : " ..Hallo everybody. I want to build a passive crossover between my JBL 2440 and my JBL 077...."

nfbertone
08-03-2012, 09:47 PM
Yes, but as it has been said : " ..Hallo everybody. I want to build a passive crossover between my JBL 2440 and my JBL 077...."...now to the 077: 1.0uF serial --------- 1,5mh parallel---------1.5uF serial -----------20Ohm 10W parallelIts sound very good! Hi Grumpy, hi Ivica, .... I think, I had to use some resitors to the horn-driver. I will check the sound with resistors -4db or -5 db...hope it works

ivica
08-04-2012, 08:04 AM
...now to the 077: 1.0uF serial --------- 1,5mh parallel---------1.5uF serial -----------20Ohm 10W parallelIts sound very good! Hi Grumpy, hi Ivica, .... I think, I had to use some resitors to the horn-driver. I will check the sound with resistors -4db or -5 db...hope it works


1.
I believe that You have mentioned 0.15mH instead of 1.5mH, because 1.5mH is tooooo much.
2.
take care that the characteristic impedance that the crossover "can see" remains about I think 8 Ohms.
3.
I have made an experiment with 0.16mH in serial with 1.5 uF cap. That would 'enhace' UHF region over 15 kHz, where 077 may has some deep in FR response

nfbertone
08-06-2012, 03:22 PM
1.I believe that You have mentioned 0.15mH instead of 1.5mH, because 1.5mH is tooooo much.2.take care that the characteristic impedance that the crossover "can see" remains about I think 8 Ohms.3.I have made an experiment with 0.16mH in serial with 1.5 uF cap. That would 'enhace' UHF region over 15 kHz, where 077 may has some deep in FR response ....what a mistake I wrote....0.15mh I used :-)) ....but with resitors to the horn driver the sound is disappointment. And without resistors the horn is toooooo superficial...

Mike F
08-06-2012, 06:51 PM
....what a mistake I wrote....0.15mh I used :-)) ....but with resitors to the horn driver the sound is disappointment. And without resistors the horn is toooooo superficial...

What do you have against L-Pads may I ask?

ivica
08-07-2012, 01:26 PM
....what a mistake I wrote....0.15mh I used :-)) ....but with resitors to the horn driver the sound is disappointment. And without resistors the horn is toooooo superficial...

I do not expect a lot of music over 10kHz.
You can try with R1=4 Ohms in series with the network 1.5uF cap, and R2=6 Ohms in parallel with 2405. i would expect about 6 dB loss in such combination, while the loading for the network would remain about 8 Ohms.

nfbertone
08-07-2012, 07:50 PM
I do not expect a lot of music over 10kHz.You can try with R1=4 Ohms in series with the network 1.5uF cap, and R2=6 Ohms in parallel with 2405. i would expect about 6 dB loss in such combination, while the loading for the network would remain about 8 Ohms....I dont want to use an L-Pad, because in my experience the sound loose a lot of dynamics. I had try the following resistors . 4Ohm ser. & 6Ohm par. //// 0,22 mh ser. + 1,8uF para. to the horn driver. I will listen to the sound few times... the first sound check was bright

ivica
08-08-2012, 02:06 AM
...I dont want to use an L-Pad, because in my experience the sound loose a lot of dynamics. I had try the following resistors . 4Ohm ser. & 6Ohm par. //// 0,22 mh ser. + 1,8uF para. to the horn driver. I will listen to the sound few times... the first sound check was bright

Hi nfbertone

can You sketch your final network. It would useful for us.

Regards
Ivica