New Life Games LLC

**Video Poker, Keno, Slots, 21** Gaming machines => IGT I-Game and Game King => Topic started by: DanTheMan on November 23, 2019, 12:33:14 PM

Title: Game King Stereo Sound
Post by: DanTheMan on November 23, 2019, 12:33:14 PM
My Game King has always played the same sound in both the left and right speakers. There was an old thread about this:

http://newlifegames.com/nlg/index.php?topic=253 (http://newlifegames.com/nlg/index.php?topic=253)

Included in that topic is a schematic. From that it is clear that there were two ways the factory could wire the sound. In one case only one sound output channel was used and it was wired to both speakers. Why? Was it perhaps an extra cost feature to have stereo sound? There's not much difference in actual cost, since it only involves adding 2 more pins to a Molex connector. So, I decided to rewire that connector to enable stereo sound.

Attached is the schematic that I marked up to show what needs to change.

The offending plug (P19) is in the top box of the machine. See the picture where two wires are connected to each of the two pin locations. These wires route to the amplifier board.

I just clipped the wires off and put a new pin on each of the 4 wires. The picture of the modification shows the 4 wires in 4 separate locations on the connector. (I can now see in the highly magnified picture that my crimps are not that great. It is a bit difficult to work within the constraints of the top box. Since the wires route behind the printer, I did not try to take the cable assembly out in order to work on it.)

The Molex pins were available from Digi-Key. https://www.digikey.com/product-detail/en/molex/0039000038/WM2501CT-ND/467978

And the pin extraction tool. https://www.digikey.com/product-detail/en/molex/0011030044/WM9918-ND/210947 It would be cheaper to buy a new connector ($0.63) and not bother with extracting the pins (the tool is $22.45), but I bought both and now have a spare tool and connector!

Before inserting the pins into the connector, I plugged them directly into the receptacle, two at a time to figure out which pair belongs to which speaker. Both pairs of wires use the same color code, which they should, since they carried the same signal when installed by the factory, so it is not obvious which is which. I did not replace the wires, rather just marked the other pair with a purple sharpie, which would have been the stripe color of the correct wire in a stereo configuration.

It's easy to run the sound diagnostics and turn on the stereo test to generate the sounds to hear the new stereo sound. Many of the test sounds have a name ending in l and a similar name ending in r. Select accordingly and start test. Stereo sounds good.

But, did I get the left sound to the left speaker and the right sound to the right speaker? Interesting question. Look closely at the schematic for the stereo configuration. They show P19 pin 5 (SPKRA+) connecting to P7 pin 7 (CHANNEL B+) and P19 pin 7 (SPKRB+) connects to P7 pin 2 (CHANNEL A-). This looks to me like the factory stereo setup would cross wire the speakers A to B and B to A and the sound intended for speaker B is wired out of phase.
Title: Re: Game King Stereo Sound
Post by: Stayouttadabunker on November 23, 2019, 12:43:05 PM
Awesome! :applause:
I'm going to try this! :yes:
Title: Re: Game King Stereo Sound
Post by: Tilt on November 23, 2019, 06:46:06 PM
Thanks for taking the time to share your experience Dan.  It will no doubt be helpful to others.  Some GK poker software only plays tones through the left speaker for some reason.  It's the way the software was written because if you go into the sound test menus you can do stereo sounds and they work like they should.  IGT did some odd things with their sound which don't make a whole lot of sense to me.

SimplePortal 2.3.5 © 2008-2012, SimplePortal