Neo 25 candy cab - left speaker (or stereo?) Not working

NoAffinity

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Neo 25 candy cab - left speaker (or stereo?) Not working

I've got a challenge with this cab. The current situation is the left speaker isn't working (testing both speakers from the test menu).

My 4-slot board is NEO-MVH MV4-FT3

How I got to this point:

1) Left speaker was working initially with no right speaker.
2) Found the right speaker wire (at pin 10) cut about 2" away from the JAMMA connector. The end that had been cut was then twisted onto the pin 11 (AUDIO + (mono)) at the jamma connector. The left speaker + wire was connected normally to pin L (Speaker + (L)).
3) I spliced the two cut pieces back together, with a soldered and heat-shrinked connection, making a good connection at pin 10 from the right speaker. Good connection still at Pin L from left speaker.
4) I then tested and am getting the right speaker working but not the left.
5) I checked the wiring at the speakers, and found (+) and (-) reversed on the left speaker terminals.
6) I corrected the wiring at the left speaker terminals, but got no improvement.
7) I tested continuity across the speakers, and am getting continuity across all four terminals.
8) I tested continuity from the in-line connector within the cabinet, and am getting continuity from the right speaker wire to pin 10, from left speaker wire to pin L, and from (-) to pin 27 (GND). Pin 10, pin L and pin 27 are also all continuous at the JAMMA harness.
9) I poked around in the soft dip settings, and found no setting to enable stereo output.
10) I have an 8-switch dip bank. Switch 7 is set to on and enables free play. The hard dip display in the test menu corroborates that free play is on, but only shows 4 settings in that menu (not 8).

What am I missing and/or doing wrong?
 
So, did some more poking around and ultimately concluded that the left speaker itself has issues. Either signal (L or R) to the right speaker works fine. Either signal to the left speaker, the speaker is producing significantly less volume.

I pulled the speaker and tested on my test rig, and same result.

I reflowed the connections at the speaker, and it seems it made a small improvement, but still not great.

So, the hunt for replacement 3" x 5" 4ohm 5W speakers ensued. I wasn't having much luck and had almost conceded to just get some 3" round speakers, which would secure to 2 of the 4 posts in the cab, but then came across these:

https://www.sciplus.com/p/OVAL-SPEAKER_50767

In my searching, I also came across a post on pinterest of someone looking for replacement baby pac speakers, which it seems these might also be suited for. So, posting here in case the find helps anybody else.

Fingers crossed that they work will in the Neo 25, and if not, then I guess I'm going the route of 3" round speakers.
 
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