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I cannot seem to find the spec sheet for the 2432H compression driver. Does anyone know if it is "red => forward motion" or "black => forward motion"?
Another question... I have just received the 5641 enclosure (the 2226H driver in a 4507A enclosure), and can see by the spec sheet of the 2226h that black => forward.. Will this mean that JBL has wired the 2226h this way in the 5641 enclosure or have they switched polarity to follow the "standard"?
http://www.jblproservice.com/pdf/The...es/4722-HF.pdfQuote:
Originally Posted by Jonas_h
I guess it's a positive transducer, if I interpret this specsheet correctly
Thakns for the answers. On the 4722-HF terminals, it says "EIA", so I guess this verifies that it is positive.
The 2226H is negative, but I dont how it is wired in the 5641 enclosure. In Stephanes document, the 5671, which uses the 5641 LF enclosure, is listed as negative, so I guess the 5641 is negative as well.
Do you know how to actually measure and verify this?
Can you find the spec sheet for this model?
Anyways, with a small battery at the cabinet terminals, you can check the polarity. Then you must assume that JBL wired the rest of the components properly for the system to work correctly.
This you can confirm with the service spec sheet.
This also could be useful: http://www.jblpro.com/catalog/suppor...=478&doctype=3
Ok that is weird.. In Stephane's document, the 5671 is described as "negative" but in the document above it says positive? Am I reading it wrong?Quote:
Originally Posted by Eaulive
Well, what it says is that there's no reverse connection on any component.Quote:
Originally Posted by Jonas_h
In some settings, it call for reversal of the mid driver for example, in order to restore phase. In this particular setup, all cabinets should be connected + on red.
Now maybe INSIDE the woofer box, the 2226 could be reversed.
Don't confuse driver wiring and cabinet wiring.
That's correct. Just connect it as labeled on the cabinet and you are fine. Have excactly the same cabinet. + to + and - to -.
Thanks
I have hooked my system up as described on the cabinets (+ to + and - to - on LF/HF). When optimizing the x-over and having the delays set, measurements showed that the best results was achieved when the polarity on the HF was reversed. After speaking to JBL, they mentioned that this is very common and is done in passive networks often too.
The system sounds great and I've achieved my goals. :)
Reversed from proper polarity, in a good design (read- coherent summation) is pretty easy to hear with A/Bs.Quote:
Originally Posted by Jonas_h
Hi
Just for my understanding, have you reversed the polarity on the high freq driver just for the measurements or have you left it reversed.
Could you just clarify what you see in your measurements?
Thanks
BUT, is the 2226 connected BLACK on + inside the cabinet? IE, Black connector of 2226 on positive lead of cabinet?Quote:
Originally Posted by Jonas_h
Hi
Eaulive.... excactely what I think it is but I haven't lookt inside the cabinet. But + is + and - is - for me on the terminal and I connect it accordingly to that.
Thanks
I left it reversed... My procedure:
- Measure impulse response on both drivers individually
- Set delay on HF so top of impulse matches
- Measure ffreq-response of both drivers playing together.
- This measurement showed a null around x-over.
- Switched polarity and the freq response was perfect along the x-over.
Se image below.
http://dl.dropbox.com/u/10759510/For..._optimized.jpg
Hi
Sorry Jonas, but I don't understand what you have been doing here.
What is your delay time?
What is your crossoverpoints and slopes?
How do you know if it is not at room issue that cause this suckout?
How does your impulse responses looks like?
How is your phaseshift at crossover point?
Why are you only measure from 80 Hz to 8000 Hz?
I see it like this, to acheive proper measurement on the loudspeaker it schould be outdoor or anechoic chamber.
Thanks