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I did a little research on these and came across a couple of comments about switching the connections to 'red to black' to put them in phase.
Anyone know about this?
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The 4313 is the professional equivalent of the L110 consumer model. They, and the later 4313B (L-110A) are wired out of phase as compared to the usual convention of a positive voltage on the red terminal giving an outward cone motion on the woofer.
Those are really excellent speakers with a mostly first order crossover, compensated for flat impedance and minimal phase shift. For their own reasons, JBL built quite a few models prior to 1980 with reversed phase, and there is a JBL technote to that effect. I had L-110's and did reverse the phase and installed 5 way binding posts on 3/4" centers at the same time, so I could use dual banana plugs on the speaker cables. The JBL connectors are designed for bare wires with an unusual put the wire in the hole and twist the connector to lock. If the wire is too fat, or too stiff, the connectors can break.
Brian mentioned that some systems invert the midrange phase relative to the woofer, and the 4313 is one of those. In this speaker, that is done because the high pass filter on the mid is 2nd order which inverts the phase. So the mid plays in phase with the woofer. The tweeter is in phase with the woofer. The 4313 crossover is quite complex for a mostly first order speaker and has something like 15 components, all of high quality. I have basically dismantled mine and have a pair of good tweeters, and four like-new LE5-10 mids. I lost the woofers a couple of decades ago. A long, sad story.
Jerry
I suppose your question deals with what is termed "absolute polarity."
Search the General Asylum for this term and you will find out why this place is considered an asylum.
RT Barr
I don't know about that model, but a lot of JBL speaker components use Black for positive and red for negative.
A 1.5V or 9V battery will tell you. Connect it so the woofer gives positive cone excursion (cone jumps out).
The terminal that is connected to the positive battery terminal is positive or "in phase".
Unless you know the phase shift of the entire system including the source material, it is at best an academic exercise. Many as invert the phase 180 degrees that when combined the the 4310 would then be in-phase whereas using the battery and reversing the polarity of the terminals would possibly result in a reverse phased system.
While reversing the phasing between the left and right speakers is quite noticeable, there is a huge disagreement when it comes to inverted phasing of a system in comparison to the source. Years ago in doing testing with systems and panels never did any member make any reference or comment related to the matter.
Also, beware that speaker manufacturers sometimes in designing multi-driver systems will invert the phase of one of the drivers as part of the design. It only adds to the confusion.
Don Brian Levy, J.D.
Toronto ON Canada
Many, MANY! designs invert one or two drivers.
I think you are on the wrong path playing with the wiring. First try cleaning all the connections, recapping and maybe even a better padding resistor.
charles
PS - I believe the 4313 is a studio monitor design. It was voiced for a flat FR response. Unlike many of the other speakers of it's day.
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