Question about speaker cab wiring

[max_twang]

Hello smart people

I just found a nice 2 x 12 empty cab on my local CL and I intend to use it for a couple of JBL K-120
speakers I've had laying around for a long time. Both speakers are 8 ohms and they will be wired in parallel
using the wires shown below.

I have a question about wiring the speakers. The cab's jack plate has two jacks. I suspect -- but want to confirm --
that these will allow me to run the speakers: 1) in mono at 4 ohms with both speakers working by plugging into either
of the jacks, or 2) in stereo at 8 ohms per jack with each speaker operating independently from the other.

I hope my question is clear. Some photos of the jack plate and wires that were inside the cab are attached.

Thanks for your help

 

[VintageSG]

I'd say no.
It looks like a standard plate that'll allow you to daisy-chain additional cabs, but they'll be in parallel.

https://www.allparts.uk.com/products/marshall-style-stereo-mono-cabinet-jack-plate

This is more what you're after.

 

[Pete Farrington]

The cab's jack plate has two jacks. I suspect -- but want to confirm --
that these will allow me to run the speakers: 1) in mono at 4 ohms with both speakers working by plugging into either
of the jacks, or 2) in stereo at 8 ohms per jack with each speaker operating independently from the other.

Per se, I’m afraid not, the sockets are 2 terminal ie no switching contacts. You’d need at least one to incorporate a switch.
You could just drill another hole and add a discrete switch, but then you’d need to remember to get it right if operating in stereo. As the outputs of 2 amps (eg stereo L and R) might not take kindly to being linked together.
Alternatively, as almost all amps have a parallel pair of speaker output sockets, you could wire each speaker to its own dedicated socket. ie no link between them. Then use 2 speaker cables back to the amp for 4 ohm operation.

 

[max_twang]

Thanks for the quick replies!

I am not particularly desirous of getting a stereo scheme set up with this cab. I was just
under the mistaken impression that that's what the two jacks were for.

Thanks for setting me straight that they are there to allow daisy chaining another cab in parallel.

I appreciate your help

 

[Peegoo]

@max_twang

You can do it with a pair of jacks; the mono jack does not have to be a switching type, but I used it in this diagram for simplicity.

 

[vanr]

Not worth the time and effort IMO. Switches go bad.

 

[Bill Moore]

If you wanted the option, here is an inexpensive remedy:

Jack Plate - Plug and Play, Mono / Stereo | Amplified Parts

The Plug and Play eliminates the confusing switch found on most stereo cabinets. Just pick your impedance and plug in. Label is set at the common 4/16 Ohm Mono and 8 Ohm Stereo. Ready to install with a steel dish, wires, and speaker connectors.

www.amplifiedparts.com