Bump-I am wondering the same thing. Anyone hook up a Polk?

Also I am considering a shaker motor. Is it worth it, is it well integrated?

Yes. Both work great.

I picked up one of the MCM external subs and I'm trying to run both MMR and GOT through it by clipping to the bottom cabinet speaker and connecting one game to the left and one game to the right high power inputs on the sub. When I run MMR by itself, it works fine. When I run GOT, it works briefly (~1 minute or so), but then the display on MMR lights up for a split second (even though it's turned off ) and then the sub sound changes to a constant clicking.

Anybody run into this before? Do I have to run one or the other of these games on a separate sub? Or is there something goofy on the MCM sub like the speaker grounds being tied together?

It looks like the speaker grounds are tied together... if I disconnect the (+) wire from MMR (leaving only the - wire to the cabinet speaker), it still mysteriously turns the MMR display on even though the game is switched off. Guess I need to come up with an external method for combining the speaker level signals. Or run separate subs.

Or just get a psw10 and you can hook two games to it.

I've got mine on an external Polk. Very bassy. Shaker motor came with the game, it's well integrated. Shakes when the castle
Blows up, when the trolls pop up and when you hit them.

If your sub has a three-position power switch (ON/OFF/AUTO), try setting it to ON instead of AUTO.

The MCM was about $95 shipped and has quite a bit better specs than the PSW10. Of course, I agree that it's unfortunate they didn't bother isolating the high level inputs, but a line level converter is only $7 so is a comparatively cheaper solution than dumping another $100+ on a PSW10.

Nope, just two positions, auto and off.

I've always run two pinball on one Polk, clipping to the cabinet speakers. I currently have MMr and AC DC. I've never had a problem. I wonder if there is something funky about the MCM: pro audio gear is always a bit different from home audio.

A $95 sub is most assuredly not "pro audio".

This thread prompted me to add a sub to my MMr. I had already installed a Pinball Pro full MMr speaker kit; I was very happy with the improvement in audio from the backbox speakers but was still looking for a little more "boom" from the cabinet speaker.

I had an old subwoofer laying around; problem was it only has line level inputs, not speaker level. I bought this $8 converter
https://www.amazon.com/gp/product/B001EAWS3W/ref=oh_aui_detailpage_o00_s00

and hooked it up last night- sounds great!

I got a similar but slightly cheaper $7 one off Amazon and it seemed to work fine with both machines connected. The only downside is that it buzzes for some reason when both machines are off, so I have to manual shut the subwoofer down rather than use Auto mode. Better than nothing I guess.

MMR uses 8 ohm in Parallel for the backbox and has a 4 ohm sub. The amp is 50wx2 RMS.

I replaced the cabinet sub with a Kenwood low-profile unit. 8", MASSIVE difference, and much more integrated than a external unit.

https://www.amazon.com/gp/product/B001ULS3DY/ref=oh_aui_detailpage_o04_s00

This is the one i got. Note, you will have to modify the cabinet and cut a larger hole otherwise you will effect the sound as the hole will be too small and the cone won't be able to move the proper amount of air.

Speaking of different systems on the same sub, has anyone successfully used the PSW10 with a SAM game and Spike game at the same time? If so, did you use the standard hook up to the cabinet speaker wires?

There's no reason why this shouldn't work. The subwoofer is designed to work with any two speaker loads and does not depend on the amplifier. I've used one PSW10 on two Sterns, two Williams, one Williams and one Stern, etc.

Not my favorite cutting a larger hole in a $8k machine... but the end result is pretty nice...