I take this opportunity to introduce you people to the idea of tuning VISUALLY.
This is something I have known since my eighth months of playing (February 2008, for those interested). It is essentially what I learnt during physics class, I love physics, and so applying it to music wasn't difficult, almost natural.
Resonance is a term some would be familiar with, but the rest will go WTF? Well don't worry; I'll be explaining it to you. Resonance is the natural phenomenon due to which a body vibrates with larger amplitude when it is exposed to a frequency equal to its own natural frequency (The definition may not be entirely correct, I just finished school around 2 weeks back, so I haven't really been studying). Didn't understand? Don't worry.
Sound is produced when a body vibrates, and when the body vibrates, a wave is formed. If the frequency of the wave is x Hz (Hz is the unit of frequency, 1 Hz is one vibration per second), and the body is moved from its position of rest, it will vibrate with a frequency of 1 Hz and if another body, with a natural frequency of 1 Hz is exposed to it, the body starts vibrating with a larger amplitude.
So what? What does this mean to the average guitarist?
Try this, tune your guitar using a tuner. Make sure it's perfectly tuned (Or as perfectly as humanly possible at least). Now put the pick down for a minute. Fret the Low E string on the 5th fret. Now Push it down towards the sound hole (Around 0.3 0.7 cms should do it).
Now suddenly let it go, not slowly, suddenly.
Oh. My. God! Yup, the A string (5th string) is vibrating.
So what? You didn't want to CHECK if your guitar was in tune, you wanted to TUNE it.
Now de-tune the A string (One or two turns should do it). Now repeat what was done with the E string, push it down a bit and suddenly let go, the A string isn't vibrating is it? Well tighten the A string a bit, repeat the pushing and releasing with the A string. Keep doing this till the A string vibrates. Yup, your A string is now in tune if it's vibrating.
Another thing to note would be that the string might vibrate even if it is a bit out of tune, you have to make sure that the string vibrates to the point where it is moved (or displaced, for the scientifically inclined) maximum from its position of rest, i.e. The more the string vibrates, the better in tune it is. Also, don't forget to play both the notes at the same time to make sure it IS perfectly in tune.
To tune your D string, press the fifth fret of the A string and repeat the above procedure till the D string vibrates. Once your D string is in tune, press the fifth fret on the D string and repeat procedure until the G string vibrates. Once your G string is in tune, press the FOURTH fret of the G string and repeat procedure till the B string vibrates. Once your B string is in tune, press the fifth fret of the B string and repeat procedure till the high E string vibrates.
The note ringing when playing the 5th fret low E string is the same as open A string.
The note ringing when playing the 5th fret A string is the same as open D string.
The note ringing when playing the 5th fret D string is the same as open G string.
The note ringing when playing the 4th fret G string is the same as open B string.
The note ringing when playing the 5th fret B string is the same as open high E string.
And whenever the same notes are played, all other fretted strings which would play the same note would vibrate. Example, on fretting and playing the 5th fret of the low E string the above mentioned way, the open A string vibrates. This method works best when attempting to make open strings resonate (vibrate), example, on playing the 7th fret A string, some of you would notice that the low E string does not vibrate, but this method will almost definitely work for having open strings vibrate.
Remember, to tune, we need a reference note; this isn't as hard as it seems to some. Just try and remember a song whose first note is an E (NOT chord, NOTE). Tune your E string to that note. Now do as written above. I find that Nothing Else Matters by Metallica works well for me.
However, if you are playing alone, you would be well off in Relative tune which means that the guitar strings are in tune with each other, however if you wish to play with others; you will most likely need a reference note. And it is advised to always be in tune to other instruments as well so as to develop a good ear.
There are other methods of tuning which I will explain, albeit not in much detail.
1. By Ear
This is pretty much the same as our method, apart from the fact that we use our ear instead of our eyes. We pick the 5th fret of the low E, and then the open A, if the strings are in tune; we proceed the same way as we did in the previous method.
2. Through Harmonics
This is a widely favored method, as it produces brilliant results. For full knowledge of this method, you might want to check out the other lessons, however I will explain the basics of how this method works, assuming you know how to play harmonics.
Play a harmonic on the 7th fret A string, and 5th fret E string. If the strings are not in tune, you will hear wavering, a phaser type sound, and as you tune the string, the sound will disappear.
The disadvantage of this method however, is that you cannot play a harmonic on the 4th fret (G string) or 8th fret (B string). To overcome this problem, I suggest playing a harmonic on the 7th fret E string and 5th fret B string.
If you are having trouble with all the above mentioned methods, you might want to consider purchasing a tuner. It is one of the wisest investments you will make, and a perfectly tuned guitar will always sounds better than one which is not perfectly in tune.
Thank you for your time, either comment and leave a suggestion and/or thank me or email me.