I've noticed that questions about "ground" come up in many threads, sometimes sidetracking them a little from the intended topic. I wonder if a thread dedicated to discussing ground might be useful? I'm going to start with a blunt opinion: It would probably be best if you forgot you ever heard the word ground. The ground. The thing we are standing on, the earth beneath out feet... it plays almost no role in the function of these gadgets we like to play with. Consider the basic common cathode gain stage: You may be accustomed to seeing a ground symbol attached to the bottom line of this drawing, but there's nothing about the operation of this circuit that requires you to connect that point to the earth. In fact you don't have to connect ANY point on the circuit to the ground. As drawn above there is no connection to earth at all (imagine V2 is a battery if that seems confusing) yet the circuit is happy to operate normally floating this way. No current is being "drawn from ground", no signal or electrons are "returning to ground". It's not connected to the ground in any way yet the tube will settle at the same bias current it always does and the input signal being applied to the tube's grid will be amplified and appear in a much larger version at the output the same as it always has. In truth you can directly connect ANY point in this circuit to the earth: and it won't make a bit of difference. I think that last one in particular may be unintuitive to some people: "If you connect the input signal to ground doesn't the signal disappear into the ground?" No. Nothing is going into or coming out of the ground. The ground is not involved in the operation of this circuit at all. That's the point I'm trying to get across here. So why are you used to seeing a ground symbol connected to the bottom of this circuit then? If nothing goes into or comes out of the ground connection, if earth plays no role in the operation of the circuit whatsoever, then what's the point of connecting it to ground at all? The answer is more simple than you might be thinking: Safety. Guitar amps traditionally make a direct metal to metal connection between the guitar and the first tube. That means whatever voltage appears on the grid of that tube appears on your strings as well. Expensive gear might have an isolation transformer on the input to prevent this from happening (and eliminate the possibility of ground loops in the studio) but guitar players are underpaid and guitar amps have rarely gone to the expense of an isolated input. Luckily, as we've already seen you can connect any point of the circuit you wish to the ground without altering how it works. So we can simply connect the point that we're touching to the earth we're standing on to avoid any potential shocks. That's probably enough for an opener. There's a lot more to say about the topic, but for step one I think trying to forget that you ever heard of anything going to or coming from ground is a good start.