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Hi,
in this simplified schematic, is E1 and E2 the external crossover binding post and E3 E4 the internal ones ?
And second question about the L102 connections can E7 E8 be reversed or is there a proper way like left bit of the inductance to E7 and right thingy to E8 ?
thanks
david
I have not seen the drawing you posted earlier, but here is
Attachment 90227
i got this pdf. but doesn t help to answer my questions... or i cant see itQuote:
Originally Posted by Odd
Yes you can swap terminals E7 and E8. The choke doesn't have a polarity. Based on the drawing you've provided ( not a schematic in the electrical sense ) this crossover board has no passive mode, it is only set up for bi-amping. You could change and add some components to make it fully passive if it does reflect the circuit on the actual schematic but its not currently set up that way. Good thing since you avoid the problems incurred by the really bad rotary switch JBL used.
Quote:
Originally Posted by davidpou
My guess is that A1 includes the switch, other assemblies are simply off board, with the diagram showing those connections. I’m not aware of any biamp-only 4430’s (but weird stuff happens). Agree re the inductor… there’s no polarity dot on the schematic or intentional coupling to another inductor which would require paying attention to which end was connected where.
Thanks !Quote:
Originally Posted by grumpy
this diagramm (?) comes from the 4430 crossover pdf namely the 3134 Attachment 90234
The context is that some years ago I asked someone to improve on the JBl network. A "kiss" idea would have been to improve caps and bypass the switch. full stop. but the guy did shit. So i made new ones entirely, reducing cables length (pots) by placing them behind the speaker attached to the back panel of the crossover itself. Ans i lived like this happily. Now I want to sell these, and as people are asking for stock speakers i started to undo what the crock did, putting everything back, just changing the wires as he cut so many of them.
So i am good for L102.
From the first page of the pdf, can you tell if E101 and E102 are for active crossover or passive ?
(i just hope the pots are working otherwise i am doing all this for nothing... ) I can test like that but i would rather start testing once correctly plugged...
Attachment 90235
I did a biased charge coupled network for sone here recently and he was over the moon.
I would see them with the original network and they can put them in after they assess with your new networks.
E101 and E102 are the full range inputs when the switch is set for full range or internal crossover and they are the low frequency inputs when the switch is set for bi-amp.
Quote:
Originally Posted by davidpou
thanks ian !Quote:
Originally Posted by Ian Mackenzie
i came across these charge coupled network (yours and GT's), but these were beyong my scope at the time. Now that i have put my hands into it, by remaking the oem one, i could probably give it a go.
My main issue with the 4430, (apart from size), are not themselve but the amps i have: the MC275 is not bad but his 75-100ish watt seems a tad short, and to my complete dispair the crown CDi drivecore 4/300 is doing worse even when tuned to make 2*600W :crying: Bloody class D !
so, if it is to use a sub anyway, then better be with smaller speakers, like 4429, for the same price here (3000-3500 €), and i will have better highs!
But maybe the charge coupled network can help the 15" woofer to move :confused:
Great ! thank you! now it s time to get the mic out.I just hope the switch is not broken nor the pots.Quote:
Originally Posted by Riley Casey
I have replied to your pm.
I would stick with the MC275 (original version?) for now.Quote:
Originally Posted by davidpou
What l suggest is obtaining a low DCR ERSE choke for the woofer and bypass the crossover switch.
Jbl used 0.5 ohm inductors on many of there systems. Add this to the 0.4 ohm output impedance of the MC275 and that damping factor drops from 20 to 9. Not ideal for a 15” bass reflex system.
Those switches add to the dcr losses due to losses in the contacts. Those switches are not really suitable for high current applications.
I can offer you a layout and schematic to re wire the charge coupled crossover and recommended parts.
I have it on good authority the results are very worthwhile.
What you might try is the 4 ohm Tap on the transformer. The woofers do dip to an impedance lower than 8 ohms at box resonance and around 300 hertz.
Work through that and see how it works out.
Beyond that you can Biamp with a high quality analogue crossover relatively in expensive.
The Crown should have a vice like grip on the woofer and you have an easy load on the valve amp.
There is a simple jfet active crossover Pass and l collaborated on or a very good Opamp based crossover we can look at. I can work that out for you if you end up going that route.
OutcomeQuote:
Originally Posted by davidpou
Wiring error identified and issue resolved.
Tip
If anyone plans to remove stock JBL crossovers always clearly label all pcb tabs, cable spades and take a pic for your future sanity. None of the factory JBL stock networks are diy friendly unfortunately.
Outcome: short circuit on E8 on one of the xover..the one I was testing first. because the pin was about to brake, and eventually did. once replaced everything was fine. the overone was working ...Quote:
Originally Posted by Ian Mackenzie
I can now compare oem to my replica... I prefer mine.... only one thing the resitance of L102.... I thinck i didn't pay attention to that and i got a lots of bass....does someone has the value , or I will put out the stock and measure myself...Quote:
Originally Posted by Ian Mackenzie
to complete the story i canged my DAC from a bryston BDA2 to a Denafrips pontus 2 (which R
R and it did some tremendous good to everything including the bass... clearly no need of sub now! amazing... I found someone to buy the 4430 , but one:
1 I never heard them like that, and
2 I cannot find any 4429 in france these days ...
so might keep them in the family for a while
Attachment 90643Attachment 90644Attachment 90645