I wonder if Polk knows about our little group and what we use their sub for. It packs a mean punch for our games.

Amazon might. I been "pingin" the crap out of their site for couple weeks checking /waiting for their price to hit bottom... It hit $79 last week for a couple of days.. I still have your restored MM too John..

Hmmm,

How do you wire them to the game?

Use some alligator clips (or crimp on some female spade connectors) to attach some wires to the cabinet speaker terminals. Improvise a way to run those wires out the cabinet (perhaps through a vent cover). Attach those wires as inputs into the sub. Done.

Nevermind. I saw your previous thread on that.

I will ask though, is there a benefit in adding a sub to a game that wasn't designed for one? IE: BTTF or JP?

JP if meaning Jurassic Park, it defiantly adds to the game I just did mine over the weekend, on low volume level its barely noticeable, but you can hear it roar with authority ..... I tend to run my games on the low volume side to edgy if its screaming at me all the time ...but defiantly the Dino roars have more punch if you crack the volume a little it really comes to life, I found I had to turn the polk volume control to max to get it to work though.

drop the sub wires on the bottom cabinet speaker hit them with alligator clips for safety and ran the wire out the back grommet where the power comes in and down to the sub you will need a switched power source or the sub will be on all the time , the switch on the sub is hassle to reach.

peace, B.

Thanks

PM sent

Now I need to figure out how to hook up to my EM's (j/K)

Is there any advantage to using the rca input rather than speaker input?

If you are connecting to the terminals on the cabinet woofer, my guess is that it's preferable to use the speaker level inputs (spring clips) on the sub, not the line level inputs (RCA connectors). That's how I have all mine hooked up. I'm hardly an expert in this area, but I would think you would only want to use the line level inputs on the sub if you are tapping into the signal before the amp.

There's other ways to hook up the sub for stern and Bally games
Nice subs!

lllvjr,

I'm glad you chimed in. Can you give us some insight into what I was saying about the line level and speaker level inputs?

That cable takes speaker level (high wattage) inputs and converts it to an RCA (low wattage) input. That probably works fine at low volumes, but I would be concerned about overloading the input circuit at higher volumes. The subwoofer is designed to accept speaker level inputs through a set of dedicated terminals (that convert speaker level inputs to signal level inputs). That's how I do it and that's how I would recommend that to any future owners of these fine units.

So it sounds like you agree with me. I didn't think it seemed like the best idea to take the post-amp signal coming from the cabinet woofer and run it into the line level input on the sub.

We added a simple resistor divider in our SAM board to cut the speaker level down by half so we could go safely into the RCA input.
The added benefit of the divider is that if the cable going to the subwoofer is shorted to ground or possibly to another speaker output of a pin sharing the subwoofer, you won't damage the amp on your pin.

From the owner's manual....

Option1.jpg

Option 2.jpg

Thanks guys, that's how I have mine hooked up and was confident it was correct til I saw that cable he's including and its connector.

I did snip off the RCA and went with the line input. In my case, the volume now needs to be turned almost all the way up to achieve the same level as the RCA input did at low volume settings. I'm sure it's safer this way though.

Sure do.

Do you leave the pinball wires connected to the speaker inside cabinet and just attach the alligator clips for sub or should you remove the original wiring to the cabinet speaker?

Also wires from cabinet to Sub should they be connected to the speaker input or speaker output?

Come on guys......

someone buy the other two subs!

(a non solicited ad)

Leave the existing wires in place, and connect the alligator clips to the same terminals. Make sure to keep track of which one is positive and which one is negative, then run the correct wires to the positive and negative speaker level inputs on the sub. It doesn't matter whether you connect them to the right or left input. Either will work, and you can use both sets of inputs to hook up two different games to the same sub.

Thanks

There is a risk of damage. Given that pinball speakers are not typically run that loud though, the risk is small.

The RCA jacks are "line level" inputs: https://en.wikipedia.org/wiki/Line_level . This type of input has been used for ages and is specified to not exceed 1.4V.

Anything driving an actual speaker is "speaker level" and has no upper bound: http://www.sweetwater.com/insync/speaker-level/ You are saved by the fact that pinball amps are not exactly super high power. However, if you turn up the volume enough, it will damage your line level inputs. The built in amplifier of WPC machines, for example, are capable of outputing as much as 25W if you crank up the volume enough ( http://www.dziedzic.us/wpc_speaker_selection.html ) That is certainly enough to damage line level inputs.

In fact, there are devices that convert speaker level to line level such as this: http://www.crutchfield.com/S-xbmtYhlSw7H/g_721/Line-Output-Converters.html . Such devices are made to ensure that the unconstrained speaker level output is converted into a low voltage line level (probably better described as a preamp level for audiophile geeks out there). The speaker inputs (the lower row of speaker wire connectors on the back panel in your pictures, but apparently different on the owners manual pictures posted above) on the Polk are a built in speaker-to-line level converter and are specifically made to accept these wires.

Dang, if you were in my city and I could pick them up they would be gone.

That's a steal. I'm shocked these are still available. My only guess is that people are hesitant to buy them because of the cherry color.

When did you get a STTNG??

come on people. If you don't like em for your games, hook em up to your stereo, or TV

It is a great pin. Been here longer than all but one of mine.

I have one of these subs hooked up to my BTTF and I must say that it tremendously improves the sound from this particular machine as compared to others. The other machine that it is great for is T2.

Hopefully not. Going to a good home though.

Thanks very much, Brian. Nice to meet you.