2226H with 2425J

[clubman]

I have a pair of both drivers layin around and would like to mate them together in one encloser. I have been runing them bi amplified using a DBX drive rack. My question is though I cant seem to find a passive crossover made for the 8 ohm 2226 and the 16 ohm 2425 horn. Could some modifications be made to a crossover that is a jbl model are could one be made from scratch. I am very good with schematics and soldering. Or am I just not looking hard enough. I would think that in some point in time they put a 16 ohm horn with a 8 ohm woofer. I beleave that the horns are from the cabiret series.

[Zilch]

http://www.jblproservice.com/pdf/Cabaret%20Series/4691B.pdf

Here's a readable version:

http://www.jblproservice.com/pdf/Network%20Schematics/4691B%20Network.pdf

It matters what horn you're using, as well....

[clubman]

Horn lens is the 2370A

[Zilch]

There's your start, then.

I have that running here, but I've never measured the response.

Party speakers. They'll play stupid loud:

http://audioheritage.org/vbulletin/attachment.php?attachmentid=27178&stc=1&d=1186512377

[clubman]

Yep, thats the idea. 2 2240H's will be covering the low end. THanks for the help!

[Baron030]

Hi Clubman
Normally, you can get all the parts you will need from a source like www.PartsExpress.com (http://www.PartsExpress.com).
But, in this case Parts Express does not carry the 0.75mH coils that you will need for your project.
As it turns out, Madisound carrys some solon 0.75mH 14ga air cores that should do the trick.
Here is the Link: www.madisound.com/catalog/index.php?cPath=356_20_31 (http://www.madisound.com/catalog/index.php?cPath=356_20_31)

Good luck with your project.
Baron030 :)

[Baron030]

D'Oh,
I forgot that the 0.75mH coil is on the High Frequency Shunt leg of the cross over.
So, you really don't need a ultra-low DCR coil.
PartsExpress has a 15 ga or even a 18ga air coil, which would work in your project.
Baron030:homer:

[jbl]

Looking at the spec sheet Zilch supplied, it looks like the 140 woofer. Not the 2226.

[Zilch]

Looking at the spec sheet Zilch supplied, it looks like the 140 woofer. Not the 2226.In the pic, you can see I've swapped in 2226H for the E140s.

The woofers run full range. I guess we could do a more comprehensive analysis and design a better crossover for either combination, but the fundamental purpose is not high fidelity here, I don't believe.... :p

[clubman]

Not lookin for super high fidelity but I dont want it sound like crap in the other hand. I am not sure that runing the 2226H full range is a good idea. I was thinking of crossing over around 1.2k as that is the maximum recomended cross point on the specs for the 2226H And would allow the horn to handle more power. I will be playing these loud. Oh they will be powered with a crown XS900

[Zilch]

I am not sure that runing the 2226H full range is a good idea.Show me how it could be worse than running E140 full range. :p

Though I can't quite read it, I believe it says 4691B is 1.6 kHz. Not a big deal to just try it, since there's only two components and an L-Pad involved.

If Johnaec'll help me, maybe I'll haul one into ZilchLab and measure it....

[clubman]

Show me how it could be worse than running E140 full range. :p



Isn't the E140 designed to run full range....hints its use for a musical instrument loudspeaker....like bass guitar.

[edgewound]

Isn't the E140 designed to run full range....hints its use for a musical instrument loudspeaker....like bass guitar.

The JBL network you're looking for is 3110A from 4671A....2425J & 2226H.

The 4691B crossover is listed as 1.6KHz on the spec sheet, but that's more of the acoustic response than the electrical.

The E140 runs full range....the 4691B is simply a hi pass for the 2425J. The E140 starts to roll off at about 2500Hz due to it's copper voice coil...and...it's sensitivity is 100dB....it screams and it's utilitarian.

The 4691B RARELY ever blew 2425 diaphragms because the hi pass is so high it's barley breathing hard at all.

[Zilch]

3110A is 800 Hz. 3120A would be 1.2 kHz. Both use tapped inductors.

[I'm workin' on it.... ;) ]

SR4725 used 1.1 kHz, and tamed the HF with a parallel tank filter. It's 2425H, tho:

http://www.jblproservice.com/pdf/SR-Series/SR4725.pdf

SR4725X retained 1.1 kHz, lost the tank, and used 3-Pole plus Zobel on the HF:

http://www.jblproservice.com/pdf/SR-X%20Series/SR4725X.pdf

Here's 2226H FR; it's 97 dB. I'm not finding E140 anywhere. :dont-know

[clubman]

Well I decided just to use the crossover from the SR4725X It matches up with the woofer and has speakons on it. I figured by the time I made a pcb and put it all together and got speakon jacks I could have just bought one. I am hoping that the horn being 16ohm doesnt cause a problem...if so later on down the road I could swap diaphrams for a 8 ohm. I wouldnt think it would throw the xover freq. off that much....if anything I would think it just wouldnt run as hot wich could be a good thing.

Now as for the box....square or trapazod. I noticed all the SR line is mostly trapazod, is this for a reason or just looks, or that you can use all of them as a stage wedge in a pinch.

[johnaec]

I noticed all the SR line is mostly trapazod, is this for a reason or just looks, or that you can use all of them as a stage wedge in a pinch.They're trapezoid so they can be placed next to each other at those angles with predictable sound dispersion and control.

John

[short_circutz]

Aren't the 2370 horns constant directivity horns, therefore needing CD equalization?

[jerv]

I have constructed and made a 2226H (nominal 8 ohm) and 2425J (nominal 16 ohm) network with CD compensation for the 2370 horn. See networks and frequency curves below.
Very nice sounding for a small PA. +/- 2.5 dB from 60Hz to 15k. Hope someone can use it.

(Sorry for the bad quality picture),

[clubman]

Sweet....like the grilles:D

Need some for mine!

http://a890.ac-images.myspacecdn.com/images01/71/l_e8ff50a9e42f76d548c58c070b91f161.jpg

[Zilch]

I have constructed and made a 2226H (nominal 8 ohm) and 2425J (nominal 16 ohm) network with CD compensation for the 2370 horn. See networks and frequency curves below.May we know R1031, the DCR of L1031, or other, please?

[jerv]

Yes, it's the DCR of L1031. Forgot to put that one in the list.

Obviously as low as possible, though values betweeen 0.1 and 0.3 ohm doesn't make much difference. (About 1/2 dB at 12 kHz). The tiny, little 0,05mH inductor I use, has a DCR of 0.25 ohm.

[JBL 4645]

There's your start, then.

I have that running here, but I've never measured the response.

Party speakers. They'll play stupid loud:

http://audioheritage.org/vbulletin/attachment.php?attachmentid=27178&stc=1&d=1186512377

“Stupid loud” nah, you mean Just Bloody Loud! I bet that glass window vibrates like nobody’s business.:D Why not use a tone and obsolete it till the window cracks.:p

[Zilch]

Yes, it's the DCR of L1031. Forgot to put that one in the list.Thank you. I may build it up to see how it works in 4691B with 2226H.

Is that actual measured system response you show, or the simulation based upon the individual driver responses?

What is the software, please?

[jerv]

Yes - if you build them, please let me know what you think!

The response shown in my prevoius post is the simulated response (because that was what I had easiest access to). Below is the simulated response (in red) shown togehter with actual measured total response (black). Quite good correlation - though I just might back up on the 7-10 kHz level by reducing C1031 slightly - to 1.8 or 2uF. Haven't gotten around to actually desolder the crossovers yet ;)

The (both simulated and measured) wiggles at 500-700 Hz are probably baffle diffraction effects. Other baffle widths might need adjustments on the LCR R2031-C2031-L2031 in the woofer circuit.

Just for fun, I also show a distortion measurement at about 96dB SPL at 1.40 m distance. Light blue is 2nd harmonic, red is 3rd harmonic. Nice, low figures.

I use lspCAD for simulation, justMLS and ARTA for measurements.

[Zilch]

Thank you for the additional detail.

I agree the peak at 7 - 10 kHz is probably making them "bright" sounding, and I would adjust it, as well.

My stock systems are a mess by comparison. :p

I have a second set of empty cabs right now, and will likely build them up this summer. Thank you for posting your crossover design; I will definitely be trying it.... :thmbsup:

[clubman]

Mine are very "bright" sounding, and I am using the stock xover. I might try out this one to see if its any different sounding. Although I am very pleased with mine now. I just dump what ever I don't want on the eq. And yes they play stupid loud!

[SMKSoundPro]

Why not just biamp the box? Call it a day.





smk

[Zilch]

Why not just biamp the box? Call it a day. 2370A is tricky when it comes to HF compensation. It's not supposed to need it, but it does.

2226H also has some anomalies that need addressing to sound best. The passives in SR have gotten more and more sophisticated since the original Cabaret designs.

Can it all be done digital? Sure. Sometimes you just want to plug 'n' play the simple stuff, tho, and if a tweaked-out passive can do it as well, why not.... :thmbsup:

[SMKSoundPro]

10-4

[badman]

2370A is tricky when it comes to HF compensation. It's not supposed to need it, but it does.

2226H also has some anomalies that need addressing to sound best. The passives in SR have gotten more and more sophisticated since the original Cabaret designs.

Can it all be done digital? Sure. Sometimes you just want to plug 'n' play the simple stuff, tho, and if a tweaked-out passive can do it as well, why not.... :thmbsup:

Hey, care to elaborate on the 2226h anomalies and crossover work? The filters in 4725 and 4725x both seem to be very simple filters on the 2226h.