Finding keys...

[smaart28]

How can I find the Key of a song or section of, by knowing only the chords. For example: if I played a B7 Fm D5 or somethin, how would i determine the key knowing that info???

[cyberfret]

B7 Fm D5 ....that would be one messed up key :) I know that was just an arbitrary example of chords. Or if those are the actual chords to a song, it is possible to have a set of chords that are not in a key.

First it is important to understand as much about music theory as possible. There is no quick answer. Your knowledge of scales, modes, chord construction, etc will help you determine a key.

I would start with the lessons in the music theory section of the site.
http://www.cyberfret.com/theory/index.php

To at least find the basic key of a song, find the chord that feels like home base. The point of resolution. Sometimes this is the first, or the last chord in the song....but not always. That will be the key. If it is an Am chord then you are in some sort of A minor key. There are multiple types of minor keys, this will only tell you the general answer. The specific minor key will only come with your study of theory.

--Shawn

[smaart28]

how would i go about determining which scales fit with what keys....if i wanted to play a solo with a particular scale or whatever.

[cyberfret]

Again that knowledge of music theory is going to be vital to fully understanding the possibilities. But if your are looking for a quick scale/key connection. Use a minor pentatonic in a minor key and a major pentatonic in a major key. You can also sometimes use a minor pentatonic in a major key if there is a bluesy feel to the song. Those are all safe, you can't go too wrong. On the other hand using a major scale would require that you know that a particular song uses a very specific major key. Where as major pentatonic will work with all major keys. Just line up the root of the scale with the root of the chord that you found to be home base. If that was Am, play an A minor pentatonic scale.

--Shawn

[VictorME]

"that feels like home base"The point of resolution"

For eample: if a have a song that uses the following chords: A Bm C A Dm A. Is there a chance that the key is A because the A chord its used more that any other chord?

[cyberfret]

In that particular example I couldn't say that you are in any one particular key. Which sometimes you can get some interesting sounds by not playing in a key. But as a general answer, the number of times a chords is play is a factor, but not the only one. It is a matter of emphasis. That emphasis can occur because a chord is play more often, or held for longer, or placed on a stronger beat.

--Shawn