The early titles of sys 1 games have a different sound board than the BR and can be converted to chimes,the later sound boards from my understanding cannot. These boards were not grounded properly and fried the chip that produced the sound .I looked for a few years and could not find the chip, or the sound board .When a board came up for sale its was as not working is or very expensive around $200. Finally to get sound I had the buy the PI-x4 ,great product and because our money is worth quite a bit more it's now around $250,I paid $350
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