I just did that to my Sinbad last week. I have done this to all my system 1 games that have chimes. I will take some pictures tonight when I get home. I typically add a connector so I can easily switch between the chimes and the sound card. I like the chimes but they are loud and makes for playing at night hard without waking up the neighbors and the rest of the house. The chimes also have a hard time keeping up when you have 3x, 4x and 5x bonus.

I would recommend making it a reversible modification if you do go ahead with it. Most people prefer the chimes for the earlier games. I know a lot of people who have owned close encounters, and have changed from the electronic sounds back to chimes.

I agree. That is why I install the connector so all I have to do is open the coin door and unplug the sound card and plug in the chimes, which I do on occasion when I want to hear the chimes. I also just lay the speaker in the bottom of the cabinet without cutting any holes or even screwing it down.

I took some pictures but did not have time to create a complete document. I can take the time to do that if there are people interested in doing this. Otherwise, just get a schematic of the System 1 sound (tone) board and go from there. The tone board is pretty simple and uses the solenoid inputs. So you just connect the chime solenoid inputs to the tone board, connect an 8 ohm speaker to the tone board and pick up the 24 vdc for the tone board from the knocker solenoid. If you need more detail pm me and I will see what I can do for you.

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