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martin2395
07-26-2013, 08:10 AM
Hi guys,
Yesterday I bought a pair of 4343's using 2235H and 2421B compression drivers, the other units are original 2121 midbass and 2405 alnico tweter.
Since they are extremely heavy we assembled them in my living room but somehow I hear that the bass response is simply wrong, the voices are too bass heavy and the bass just sounds bloated and boomy.

So the question is: What is the right way to connect the units? The woofers are connected like this now: Green(+terminal), Green-black(-terminal)

I've already read the other topic about 4343 wiring but now I'm even more confused...
I'm using a Threshold T 200 amp, MIT330 interlinks and standard copper speaker cable.

martin2395
07-28-2013, 01:54 PM
The units are connected like this now:

JBL 2121 midbass:
Black = white/black
Red = white

JBL 2235H woofer:
Black = green/black
Red = green

JBL 2423B mid:
Black = yellow/black
Red= yellow

JBL 2405 tweeter:
Black = red/black
Red = red

Is this correct? The crossover network is 3143.
I've discovered a fault in one of the woofers but it's fixed now and the other was wired different, though I'd like to be sure that everything is connected all right.

Earl K
07-28-2013, 02:18 PM
The units are connected like this now:

JBL 2121 midbass:
Black = white/black
Red = white

JBL 2235H woofer:
Black = green/black
Red = green

JBL 2423B mid:
Black = yellow/black
Red= yellow

JBL 2405 tweeter:
Black = red/black
Red = red

Is this correct? The crossover network is 3143.
I've discovered a fault in one of the woofers but it's fixed now and the other was wired different, though I'd like to be sure that everything is connected all right.

What have you previously read ( that gave directions ) ; Polarity & 4343 Wiring ? (http://www.audioheritage.org/vbulletin/showthread.php?487-Polarity-and-4343-wiring&highlight=wiring)

From what you've posted, I think you have the polarity of the woofer section flipped backwards ( try ; Green-2-Black & Green/Black-2-Red ) .

:)

martin2395
07-28-2013, 02:32 PM
Thank you for the info Earl, very helpful!

Yes I read the other topic, but then I read JBL's tech sheet about reversed polarity and got confused :)
Well this could possibly clarify the bad bass response as the cone was moving in the wrong direction and the other woofer had a bad connection between the spring connectors and the voice coil.

+
By the way, I plan to bi-amp my 4343's in the future using the 5235 crossover but do I still have to route the 300Hz and above signal through the electronic crossover (assuming it has 300Hz cards in it)?
Or does it go like this:
Preamp OUT1 -> JBL 5235 -> AMP1 -> Low section of the 4343
Preamp OUT2 -> AMP2 -> Mid/Hi section of the 4343

Thanks in advance!

martin2395
10-23-2013, 05:16 AM
Just FIY so people won't get confused about polarity of the 4343:

All units in the 4343 are negative RED / positive BLACK (2421/2121/2405/2235)

In stock form the black terminal of the speaker goes to red terminal on the amplifier (to make speaker cone move outwards)

You can rewire the units to have the modern standard with positive red, that's what I did on mine.

subwoof
10-24-2013, 06:21 PM
if you could SEE the woofer cone move then you have some serious amplifier / power distro issues. This is not like the movies - if a cone is flopping around then too much LF material is being sent to the cabinet, the power supply / output on the amp is compromised or a combination of all of them...

Check all your electronics and make sure there isn't an external problem before blaming the polarity or component(s)..

sub

martin2395
10-24-2013, 11:06 PM
I know what you mean but I was testing the polarity with a 1.5V battery to see the cone moving ;)
At normal use, I only see the cones moving while playing the 1812 overture :D

I use a Krell KSA50 (recapped) to drive my 4343's, should be enough.

pyonc
10-25-2013, 07:32 PM
I know what you mean but I was testing the polarity with a 1.5V battery to see the cone moving ;)
At normal use, I only see the cones moving while playing the 1812 overture :D

I use a Krell KSA50 (recapped) to drive my 4343's, should be enough.

For my 4343 biamped set-up, speaker Red to goes to amp Black for LF. For MF/HF, speaker RED goes to amp RED. :)

martin2395
10-26-2013, 01:10 PM
Sounds like you have the mid/high section wired out of phase to me ;)

pyonc
11-03-2013, 11:36 AM
Sounds like you have the mid/high section wired out of phase to me ;)

That's what I got from our Forum gurus about previous threads on this.
Then, speaker black goes to amp red for M/HF in your case?
And what about it for LF?

pyonc
11-03-2013, 12:25 PM
Just FIY so people won't get confused about polarity of the 4343:

All units in the 4343 are negative RED / positive BLACK (2421/2121/2405 (tel:2421/2121/2405)/2235)

In stock form the black terminal of the speaker goes to red terminal on the amplifier (to make speaker cone move outwards)

You can rewire the units to have the modern standard with positive red, that's what I did on mine.

So, speaker black goes to amp red for LF (2231), which I did?
Or the other way, speaker black goes to amp black?

martin2395
11-03-2013, 01:14 PM
The gurus told you so, because you are probably using a 18dB/oct active crossover :)
In passive mode and while using 12/24db crossovers all units in the cabinet are wired the same.

With stock 4343's (thus the internal connections: black wire->black terminal) your black terminal on the back of the cabinet should be connected to the red one on the amplifier.

pyonc
11-03-2013, 01:46 PM
The gurus told you so, because you are probably using a 18dB/oct active crossover :)
In passive mode and while using 12/24db crossovers all units in the cabinet are wired the same.

With stock 4343's (thus the internal connections: black wire->black terminal) your black terminal on the back of the cabinet should be connected to the red one on the amplifier.

Well, actually I' m using Ashly 24db/oct active crossover in a biamp mode.
And this is my set-up. Just tell me if it's wrong with JBL stock 4343. :blink:
*speaker terminal black to amp black M/HF
*speaker black to amp red LF (2231)

martin2395
11-04-2013, 12:54 AM
I think that your mid/hi section is out of phase with the woofer now, unless they are wired different inside. :dont-know:

pyonc
11-04-2013, 02:31 AM
I think that your mid/hi section is out of phase with the woofer now, unless they are wired different inside. :dont-know:

I didn't modify the wiring inside.
So, do you mean speaker terminal black should go to amp RED
for M/F to be in phase with LF?