sepheritoh
Andrew
You are right about the layering of the guitars. Jimi Page and also SRV used it a lot, but not always with the widening effect. Sometimes it is done simply to obtain that unique tone. I can be wrong but I think I read somewhere that Eric Clapton with Cream virtually invented the technique with the recording of White Room. The intro is done by recording six strings individually feeding back, instead of playing a chord. This might be a urban legend about him inventing the technique. Jimi Hendrix layered his guitars as well, but rarely playing the same part over. He layered it by doing similar, but not identical solos. IIRC even Jeff Beck used it. Incidentally 3/4 players mentioned above started off in the same band.
In the 80's the technique of layering guitars became a standard in recording. Almost a signature thing for the Glam Metal bands of the time. Def Leopard went the extra mile to create their wall of sound. Trevor Rabin did a great job in creating variations on the theme when he recorded his 3 solo albums of that time. Today, it is still being used everywhere. A great technique to create the right effect.
AlanRatcliffe
Les Paul was the first to multitrack guitar parts. He invented both the technique and the equipment to do it with - A real Renaissance man.
To multitrack guitars the key is not to make any of them too complex in tone or harmonically. Tonally, Brian May is a great example, as each of his guitar parts will be very thin sounding and with surprisingly little distortion by itself, but when the parts are combined, they give a huge, heavy sound.
Harmonically, break each guitar part down so it is simpler - single notes, intervals or triads rather than full chords. Once again, the complexity comes from the combination of parts. Seph mentioned Def Leppard and they are a great example of this - they play really complex chords that you wouldn't usually be able to with one guitar and that amount of distortion. So they break each chord into two triads or intervals and each guitarist essentially plays half of the chord.
sepheritoh
Alan thanks for those tips. I make the mistake far too often to add far too much effects and distortion on individual parts.
Interesting facts about Les Paul. Thanks. I will look it up a bit. Any specific recordings you can recommend me to listen to?
AlanRatcliffe