5235 electronic crossover

[Ken Pachkowsky]

Molex 0.156" PCB Connector, 6 pins.

Mouser #538-09-52-3063

Look right?

Yo Zilch, thanks for helping out. I just got back.

Ken

[mvaldes]

well... thanks to the very precious help you gave me, I've made the 52-5130 card for my 4430.
I followed the schematic and photos of the PCB found here in some other threads. Thanks again.
I now just want to check if I've made a correct job or not
I'm posting here two images showing the Low pass and High pass exit of the 5235 xover whit my 52-5130 clone cards
Just want to know if someone have the stock cards and can compare the result

[boputnam]

Michelle...

I don't know what you're searching for, but that crossover point looks a bit high at ~1,700 Hz...

I also think the slope on the Hi pass looks far too gentle - but again, don't know what you were designing for.

[mvaldes]

this is exactly what I noticed.
Looking at the RTA I've posted here, the lowpass of the 5130 clone card seem tuned at 1Khz with 18db slope (in fact, at 2Khz is about -80db in the RTA scale), and this should be Ok...I guess...
But the Hipass it's little bit strange.
This is the reason why I'm asking if somebody that have the original 52-5130 from stock have ever noticed that or if can make this simple test with the RTA
Maybe I've made some mistake on my clone cards...

[Robh3606]

Hmm

Those outputs look a bit strange but for the high end you have a series 20uf cap and the compensation in the network as well. That tailors what the drivers actually see. Not sure if the voltage drives previously posted were the raw output from the crossover or the entire network. I would guess they are the entire network. What does the curve look like at the driver with a dummy load across the network??? If that matches the posted drives I would think you would be fine.

Also remember these are CD horns so you want the drive down low attenuated. The curve should basically be the inverse of the roll off the driver has above 2k or so.

Rob

[Zilch]

I have the cards, crossover, passive network, drivers, horns.

Tell me what you want to see.

It's unclear what you're showing there. It looks like the 5235 only without the passive network before the drivers? Or is that 4430's HF and LF separately playing with the 5235 driving the "ext" inputs of 4430?

If so, the HF shouldn't be climbing like that.

[Nice display, tho.... ]

Giskard posted the 5235/4430 voltage drives early in the Q&D 4430 thread, IIRC....

[mvaldes]

what I posted here is just what I get from the High and Low exit of the 5235 crossover driven with pink noise.
I'm driving the 5235 with Pink noise generator and then sending the 5235 output to the RTA. The two images are captured into two different moments. First one is just the Low pass (low exit on 5235) and second one is just the high pass (high exit on 5235)
As i wrote before, I made by myself the cards for the 4430, but before using these homemade cards I want to be sure that I made them correctly

Zilch....if you can, please try to make the same test, so I can see if my cards works correctly.

I'm sorry if I haven't explained so well what I need, but English is not my first language, as you certainly understood....

[Zilch]

No problem. I'll reconfigure some stuff and make it happen. Not gonna be as pretty as yours, tho....

[Zilch]

O.K., here they are. That's my 26 Hz bump filter at the bottom of the LF there. It's documented in the early pages of Q&D 4430's also.

[Looks like it's working. ]

I'd say your HF is wrong.

Curves are here:

http://audioheritage.org/vbulletin/s...ead.php?t=1159

See also posts 93 and 99 here:

http://audioheritage.org/vbulletin/s...8&page=7&pp=15

Hope this helps....

[mvaldes]

Thank you very much Zilch

.....I've double-checked all things but I can't figure out what's wrong
I've used the same schematic and components list that Giskard posted in the thread you suggested me to look at.

As a guideline, I've also used the PCB photo posted here
http://www.audioheritage.org/vbullet...hlight=52-5130
I really don't know what to do....
Zilch...., have you used for your measurement the 52-5130 card from stock ?
The RTA curve you posted here is just the 5235 output or it's the combination of 5235 + 4430 passive crossover ?
Sorry if I asking that, but just want to be sure of this and try to understand what's wrong with my cloned card

[Zilch]

I did what you described. RTA out to crossover in (both channels). Crossover high out (both channels) to RTA in. Display line in (L+R).

Repeat for crossover low out.

No passive, amp or speakers connected.

These are factory cards, yes, all original, which Robh kindly swapped with me. That's them in the pics in the link you provided, most likely.

I cross-checked the drawings in the several links, and they all seem the same.

Mine are down 3 dB at 1250 Hz, and seem to match the posted curves. Yours are already down at 20 kHz. Check your capacitor and resistor values. C4, R4 are the HF, looks like, 0.01 uF and 13 K. You have 0.001 uF in there maybe?

[Ken Pachkowsky]

Check your capacitor and resistor values....

Yep, thats all I can think of as well. I am pretty sure you got the right values.

Ken

[4313B]

The schematics and component values were taken directly from the production drawings. They could be wrong I suppose. One thing I've learned over the years is that JBL has never been real big on proof reading. In fact, I just finished proof reading a new Engineering Design Specification a few weeks ago and notified the author of an error. Mistakes happen.

[mvaldes]

believe it or not, I've checked several time the value of the capacitor, In particular the ones related to the Highpass section

But, as probably you already know, sometime What You See Is What You Hope....
Actually, after the last check, I've found out that the C4 I used was 1nF (0,001uF) not 10nF (0,01uF) has it must be
Zilch....you thought was right
Here is the new RTA plot. It look much better now
Thank you very much guys for your suggestions and patience.

[4313B]

Good.

I try to be as meticulous as possible with the data and schematics.