I've been off a lot recently (finished school), which has resulted in me playing the guitar more (probably about four hours a day), and my playing has been unusually messy recently.

Normally I can play the riff to Snow ((Hey Oh)) quite well, up to speed and everything, but recently I've been picking very badly (hitting the wrong strings, etc.) and on the hammer on I've been not making a very strong connection with the string, and basically going to far down on the guitar (not hitting the next string, but not hitting the one I want cleanly).

Now, that's quite a fast song. It's not because it's fast I'm messing up though, I've tried slow songs such as fluorescent adolescent, and I've been playing them quite messily too (not the strumming, just the single note picking for the intro/riff), I get fret buzz sometimes, and don't hit the string properly.

However, my vibrato, legato (even though it's bad for that song, it's good for everything else), string muting, finger picking and improvisation has never been better, and is improving all the time.

What the hell is going on? I've been playing guitar for six months, and all the songs I'm messing up on are songs I learnt a minimum of a month ago, but it's not like I don't practice them, I play them everyday just to please myself. lol. However, I'm having no trouble with new songs I'm learning (Jimi Hendrix - Castles Made of Sand, John Frusciante - Song to Sing When I'm Lonely).

So yeah... What's going on?
Maybe your ears are picking up mistakes they couldn't before. It happens when they mature musically.
"Swords, nature's hell sticks."- Trip Fisk
Take a short break, maybe three or four days. I've heard guitar being compared to working out, you have to take a break once in a while for the best outcomes. Also, even if you think it's not the speed that is messing you up, bring the tempo down a bit so that when you play you have some room to think and play the next note cleanly. And hey, you've been playing 6 months, you have a lot of time to improve
just slow down your playing to a speed you can play everything perfect and then slowly build your speed back up
Quote by mtforever
Maybe your ears are picking up mistakes they couldn't before. It happens when they mature musically.

It may very well be...

Also, I get that problem when I play too much time. Musical tiredness I guess...

Just give it time =)

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wait- you've been playing for 6 months and you can play Snow (Hey Oh) ?

man i've been playing nearly 2 years and i struggle with that ****
Yeah dude take a break! 5 days the max.
I remember sitting infront of my Guitar Pro two months ago learning Laid to Rest by Lamb of God. I couldnt get the intro down to speed so I left it alone for a week. Then it just "clicks". I got it!
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Thanks for the advice guys.

I think I'm going to leave some of the songs I'm struggling with, and focus on learning a new genre.

Also, I kind of n00b question, but does anybody have a good page explaining barre chords? I can play them, but I don't understand the theory behind the different shapes, etc. and none of the other tutorials I've been to have been much help.

Oh yeah, are there any simple websites with scales on them? The other day I found a tutorial here with all the boxes for A minor pentatonic, which helped a lot, as I could then work it out for different keys quite easily, and new the shape. However, most tutorials seem to go into intense theory about why I'm playing this, and don't really give much detail on what the actual boxes and box shape is. I'm interested in the major scale (Yeah, I know this should have been the first one I learnt, but I can't find anything I understand on it. lol), blues scale, and anything else you think I'll like.

Zida, that's the point... I can't play it anymore. lol.