Hey I got a Peavey 112 solo series 160 watt guitar amp and I have a lot of questions about it. first off i would like to know about how old it is. B ut mor importantly, I want to know what all the switches and inputs are used for, OK it has the following that i want to know what their functions are:

-a little 3 way switch on the face that says GND.??
-high gain low gain inputs(whats the difference?)
-2 effects inputs on the face send and return?
-And on the back it has a POWER AMP in, a pre amp out,and aremote awitch in put.
THANK YOU VERY MUCH!!!
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