I could have dug up an even older post about this !
I have had a GRE PSR-600 for years and I like it so much that I just purchased a Pro-197 on sale for $300. The only thing that I do not like about these GRE scanners is the volume is just too loud. So what can I do about this ? I opened up one of these scanners today and removed the white + wire from the speaker. Then I tried various sizes of resistors. I would soldered the white wire to one end of the resistor and the other end of the resistor onto the + speaker post. I settled on a very tiny resistor that gave me the just result that I was looking for. I now have that scanner's volume set at the 2:00 position for easy listening. It sounds great now. What was the value of the resistor that worked so well for me ? You guys can try this on your scanners and find the result that works best for you. Good luck and have fun with it.