I am having extremely loud string noise or hissing sound from my guitar when using distortion. It only goes if I block all the strings with my hand. The hissing sound is louder than when I play the actual notes so it ruins the whole sound of playing. I cannot record with this sound. It'll ruin the whole thing. Is it because I am using passive pickups? If I use active pickups will the hissing sound go? Can it be from electronic interference and from all the coiled wires from other devices? Do the other devices still interfere even if they are off? Is it possible to get rid of the hissing sound with passive pickups by grounding?

Try turning down your volume knob a little.

I think there is a little flaw with the wiring of your guitar

__________________

How old is your lead? I just got a new lead cuz my old one was getting pretty tired. It fixed a lot of the shitty noises.
you could get a guitar tech to check it out.

__________________

I have the same problem (well, the hissing is never louder than the playing) , but only through my EMG active pickup. I have the EMG in the bridge, single coil in the middle and humbucker in the neck (both stock ibanez pickups) If I switch to these then the hissing gets a bit quiter. Also this only happens when there is a TV switched on, or a computer on in the same room... I also have crap cables which adds to the hissing aswell I guess.

__________________

Could very well be a dodgy earth on your guitar or amp. Get someone with electrical experience to check the wiring on your gear.
Is your amp picking up interference from nearby electrical gear such as computers or lights? I used to have a problem with picking up radio stations when I used my wah!

Another good tip, that was mentioned above is buy really good quality guitar leads as cheap or old ones pick up all kinds of interference and deplete the sound.

__________________

If you have single coil pickups then the hissing is going to be there around anything like TVs and monitors. My suggestion is to get a MXR Smartgate. I use one and it cuts down on any unwanted shit that you don't want. You can be playing something and stop real fast and you don't have all that finger movement or shit that comes after the stop. It also can reduce/remove hissing.

__________________

It is probabaly a bad ground in the wiring of your guitar. That and/or you are playing close to a TV or computer that is on. Shitty cables will add to it, aswill a high gain shit pedal I assume you are using, no offense.

__________________

sounds like a wiring problem, if it was electromagnetic interferance, it wouldn't go away when you mute the strings.
also, get a noise gate.

__________________

Where's the earth usually in a guitar?

Mine buzzes/hisses if im not touching anything metal on the guitar. It goes away if i touch the strings, bridge, volume knob ect.

I figure thats the grounding?

__________________

The earth is soldered to the volume or tone pot and then connects to the bridge.
EMG's are internally shielded and do not require string earthing.

__________________

Yup, sounds like a grounding problem to me too. And like stated before, EMG are not to be grounded. That might be the whole problem, because I think EMG are reverse polarity from most other pickups.

__________________

I get that too, I have an EMG81 in the bridge and a passive humbucker at the neck, and only if I stand too close to my computer monitor when it's on - but my distortion pedal is cheap and shit which doesn't help.

It helped bringing the volume down. If I leave my guitar still it doesn't hiss but if I move it in any way it starts to hiss. When I play a note on the guitar and leave it for a really short time the note gets cut off by the hissing sound (if I'm playing notes continously without stopping it doesn't hiss). Than I realized I get rid of the hissing sound by mutting the string on top of it or one of the strings untop of it. The strings that make it hiss were the third string (F) and the 6 string (Fat D). If I play and block those two strings while playing it takes the hiss off completely but it is hard to keep muting those strings while playing. It takes of my concentration. I can hit a note like that and it'll last without being cut by the hiss sound. I have no idea why those two strings make my guitar hiss in loud high pitch discorded sounds. Maybe an MXR Smartgate or a noise gate will solve the problem, but don't they take off from the tone to cancel the hissing sounds? When you say wiring problems do you mean the actual internal wires of the amp and the guitar or the layout of my cables? How do you ground a guitar or the pickups?

Do you have another amp or stomp box you could try your guitar through? If you use another amp etc does it still hiss? If you use different leads does it still hiss? If it does it could be the guitar. And it'll be the internal wiring on the guitar which we refer to. To check this take off the scratch plate or back panel on your guitar to expose the wires. Do a visual check to see if any are loose, disconnected or damaged. You should see a wire come from the volume or tone pot and disappear into the body of the guitar in the direction of the bridge. If you find it check to make sure it's connected. If you can't find any wire going to the bridge that could be the problem.

You don't say what amp you use or if you use a distortion pedal, if you do which ones? It could be the distortion pedal as some of the cheap high gain ones squeal like bugger when you stop playing, maybe try backing the gain off a little and make sure you are playing it through the clean channel on your amp and not the dirty channel with the amp gain turned down as this can add extra hiss and squeal.
Don't know if that helps any?

__________________

I checked the wiring. The connections seem to be in place. What I think the problem is I have to tailor the guitar adjustments because I changed the gauge set strings from 11-49 to 9-42 and that changed the string tension making my neck go closer to the strings thus making it buzz. Do looser string tension make the neck bend closer to the strings? Do you solve that with the tross rod adjustments?