I had bought a sound chip from Replicaprops:
https://www.replicaprops.com/cart2/index.php?main_page=product_reviews&products_id=114
and had gotten a decent sound out of the system and most importantly, it was cheap to do.
I have bought a second sound chip for another proton pack I am making. I really investigated different sound boards before choosing this one. This is obviously a great deal, the cheapest way of getting sound for a Ghostbusters proton pack. But I also needed a good sound to it, loud and crisp. I had done a decent job with the last chip I bought. BUT… I wanted something a little better. The great thing about this system other than the great price is that it is really simple to put together. Pop the chip on a bread board, put the wires in the corresponding chip leg spot and wire it directly to the batteries, switches and speakers. To get past the extra loud sound system, I had to be just as creative as this system is in simplicity. I found an Ipod speaker system that has 2AA batteries as a sound booster. I purchased this exact speaker here: Amazon.com
The great thing is it has its own power source for a sound booster. By cutting the plug off, you will expose a copper wire, grey wire and yellow wire. I connected the grey to the negative and yellow to the positive and did not connect the copper. With a modification, this already good sound system suddenly was very loud and powerful. For about $ 15 dollars, it is a great way to enhance an already strong sound system and keeping a very low budget doing so at the same time. You would have to spend quite a bit more of monies to get an equivalent sound quality and level with other systems currently offered on the market.
So again, extremely happy with this sound chip and the easy use, and price to create a really nice sound system for yet another proton pack prop project. I absolutely recommend this system, it allows for quite a bit of leeway in creating an ultimate mid to high power prop sound system.
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