4333 / S300 / L300 equivalent bandbass circuit

Yes yes, first post and I'm reviving the dead and buried :D
But why start a new thread when this one is perfect.

I'm renovating a pair of home built speakers (2215h/2420/2405) and will be using this crossover so kindly supplied by 4313B.
But I have one question.
As I don't have the variable L pads, could you guide me as to a suitable fixed resistor solution for both the mid and tweeter pads please ?
Thank you.

Quote:

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Originally Posted by 4313B

Here is the schematic.

It's voltage drive is a dead ringer for the original voltage drive as measured on December 16th, 1975.

Most of the components are available from Parts Express. The LF inductor is the 14 gauge perfect layer wound air core. For those who like the signature JBL bass hump at ~ 30 Hz you may need to tune the enclosure up a couple of Hz. All the MF inductors are the 18 gauge perfect layer wound air cores.

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Quote:

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Originally Posted by OldManWagon

Yes yes, first post and I'm reviving the dead and buried :D
But why start a new thread when this one is perfect.

I'm renovating a pair of home built speakers (2215h/2420/2405) and will be using this crossover so kindly supplied by 4313B.
But I have one question.
As I don't have the variable L pads, could you guide me as to a suitable fixed resistor solution for both the mid and tweeter pads please ?
Thank you.

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Welcome to the forum... can't help with the specific question, but you need a different network since you are using the LE15A/2215 woofers instead of the 136A/2231A that this network is designed for.


Widget

Thanks, hi.

I'm using the 16ohm 2215h, with a change to the bass section of this crossover.
(zobel 13.5uF 10 ohm, filter 3.3mH 12uF - Copied from the 3110 crossover).

ok, so next question (related) would be, if the 2420 and 2405 are ~10ohm impedence, with the 20 ohm across them gives ~8ohm 'driver' as seen by the crossover, so therefore, if i know the sensitivity of the drivers, I can calculate the required L-Pad values.

So if;
2215 = 96db/w/m
2420 = 118db/w/m (24db pad ?? whats the real output of this driver when mounted to a horn/lens ??)
2405 = 104db/w/m (8db pad)

Can anyone see anything obviously wrong with those numbers ?
Or have any comments..

At this stage I'm going to build the crossovers, with fixed L-pads of around 10db att. in place of the variable ones, and fine tune levels by ear and frequency sweeps.

[QUOTE=OldManWagon;311738]Thanks, hi.


So if;
2215 = 96db/w/m
2420 = 118db/w/m (24db pad ?? whats the real output of this driver when mounted to a horn/lens ??)
2405 = 104db/w/m (8db pad)

Can anyone see anything obviously wrong with those numbers ?
Or have any comments..
....

my experience with 2420 with 2308 Lens and 2307 the sensitivity is about 106~108dB/1m

Quote:

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Originally Posted by 4313B

As per a PM today here is the schematic for bi-amp only L300's, S300's and 4333's.

I personally would bias (charge couple) them.

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Capacitor-"serial capacitor" to the MID section would be well-come in order to protect
242x compression driver
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Attachment 51323

Quote:

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Originally Posted by ivica

my experience with 2420 with 2308 Lens and 2307 the sensitivity is about 106~108dB/1m

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Cool, Thanks.
Made up the crossover and had a play, Around 9-12 DB Att. on both mid and tweeter seem roughly the area to aim for.

This may be a different thread question but has a S8/S20 charge coupled network been worked out to replace the LX5/N7000-N8000 combo? :confused:

Has anyone put out a diagram for a charge coupled crossover at 500 and 7000 hz? Or can someone note the mods to the Charge coupled l-300 crossover to change it to 500 and 700hz. I am proficient with the restoration and repair thing, but when it comes to design of the crossovers, I wish to leave it to those with more experience. Any help would be greatly appreciated.

Thanks

MB