Wire Colors........again! 123A-3

[KT88Lover]

Tomorrow I will be finishing up my L100(A)s restoration. I picked this pair up May 1st and have pushed hard to get them done. They are beautiful.

The wires to the 123A-3s were connected:
BLACK wire to RED woofer terminal
GREEN wire to BLACK woofer terminal

I have the tech sheet but it does not make notation of terminal color, only a drawing of the circuit.
I just want to double check before I button everything back up as I have read somewhere here that one of these woofers was wired contrary to the norm.
To my knowledge I am the first person to have taken these out but I'd still like to be certain.

Regards to all,
Jim

[KT88Lover]

I found a thread discussing this question; indicating that the 123A-3 is a negative polarity driver, ergo, GREEN wire to BLACK terminal and BLACK wire to RED terminal, so for this loudspeaker system the wiring was correct.

I would still like a confirmation that this is indeed correct, please.

Other than these "reverse" polarity drivers being an old JBL convention, why?
Isn't it ultimately just a matter of what color button you put on the terminal connector? I know in a lot of vintage speakers like "AR" they put the caps on the "negative" side. Since it's AC why did anyone change anything?

Seems as if marking drivers in the opposite of what you would expect gives rise to more opportunity for error; is it something done for the hell of it? Or am I just too stupid to understand the technical reasons behind it?

Thanks men,
Jim

[badman]

I found a thread discussing this question; indicating that the 123A-3 is a negative polarity driver, ergo, GREEN wire to BLACK terminal and BLACK wire to RED terminal, so for this loudspeaker system the wiring was correct.

I would still like a confirmation that this is indeed correct, please.

Other than these "reverse" polarity drivers being an old JBL convention, why?
Isn't it ultimately just a matter of what color button you put on the terminal connector? I know in a lot of vintage speakers like "AR" they put the caps on the "negative" side. Since it's AC why did anyone change anything?

Seems as if marking drivers in the opposite of what you would expect gives rise to more opportunity for error; is it something done for the hell of it? Or am I just too stupid to understand the technical reasons behind it?

Thanks men,
Jim

Quit bein' so dumb, ya dumb dummy! ;) j/k

The reason I see is that the drivers are often used in completed systems with inverted polarity due to the phase alignment of the driver/crossover combination. When this is the case, it's actually easier to keep hookup straight by inverting polarity on the driver side.

[KT88Lover]

Quit bein' so dumb, ya dumb dummy! ;) j/k

The reason I see is that the drivers are often used in completed systems with inverted polarity due to the phase alignment of the driver/crossover combination. When this is the case, it's actually easier to keep hookup straight by inverting polarity on the driver side.

Understood, but JBL, as I have learned here, builds or has built "negative polarity drivers".

I also understand the 123A-3 to be such a driver (I haven't done the ole battery test). In this pair of L100As not only is the driver "reversed" voice coil wise but the wire color to terminals is a departure form what is generally considered "standard", with the BLACK wire going to the RED post?

Just seems convoluted to me.

Thanks,
Jim

[JBL 4645]

Understood, but JBL, as I have learned here, builds or has built "negative polarity drivers".
Jim

I believe the JBL 2240 that I use is negative polarity. I have notice this with the other speakers that have there polarity set to forwards, damn confusing unless you know what to look for with sine wave.:D