Applying chords/scales to songs

[papathaddy]

I'm new to chords and scales, but i am trying to figure out good ways on applying them to music. How do i figure out what Key the song is in? What are popular some popular keys that sludge/thrash rock use? Also I know the popular chords on a guitar, most of the time bass would hit the notes in the chord arpeggiated?

 

[MalcolmAmos]

I'm new to chords and scales, but i am trying to figure out good ways on applying them to music.

From the top. Music is made from melody (scales), harmony (the chords) and rhythm (the beat or note duration).

Chords harmonize the melody, i.e. melody notes and chord notes should share some like notes for harmonization to take place. If we played the melody to Mary Had a Little Lamb in the key of C the melody notes would be. E-D-C-D-E-E-E. OK we now need a chord under those notes for harmony. Since the song is in the key of C and the notes of the C chord are C, E & G the C chord shares notes with that melody phrase and ends up being the best candidate. Now when the melody moves on to melody notes not found in the C chord we have to change to a chord that has some of the new melody notes in it. Invalid Link Removed So keeping it simple - the melody comes from the scale and the harmony comes from the chords played under the melody notes. I've listed some fake chord sheet music on Cold, Cold Heart at the end of this post. Notice the chord progression is the same for each verse. This is not rocket science.

How do i figure out what Key the song is in?

• You listen for the tonal center of what is being played. Sound your G string one fret at a time when what is being played on the CD and what you are doing sound good together you've found the tonal center. Look down at what note on your fretboard that happened on - that's your key.
• Easy way is to look at the last chord in each verse. If all the verses end with the same chord that chord's name is your key.
• Look at the sheet music and see if it has a key signature, i.e. ### three sharps tell us the key for this song is A major or F#m the relative minor of A major. A major and F#m have the same notes and same chords. If the song revolves around the major chords it is in A major. If the song revolves around the minor chords it is in the key of F#m.
• Or perhaps the easiest way is to just ask one of the band members.

What are popular some popular keys that sludge/thrash rock use?

I know nothing of sludge/thrash, however, Pop, Rock, Country and Blues will probably be one of the major keys such as:
C, G, D, A, E. If you have horns, and sax they like the flat keys, Ab, Eb, etc. Since jazz will use horns and sax it will probably be in C perhaps G and then one of the flat keys. The vocalist plays a big part in what key will be used. Vocalist like to sing in the key they feel comfortable with, i.e. can hit all the high notes and all the low notes. I like D. Can I sing in other keys? Sure, I do it in church all the time. Now if its in something other than D I may not hit all the high notes dead on, so if I have a choice I'd ask for D.

Also I know the popular chords on a guitar, most of the time bass would hit the notes in the chord arpeggiated?

Correct. Cmaj7 chord notes are the R-3-5-7 scale degrees of the C major scale or C-E-G-B. At first you could try this:
Root on the 1 beat. If you have room add a 5, i.e. R-5-R-5 need a little more get an 8 in there R-5-8-5. Still have room and need something else bring in the correct 3 and 7. R-3-5-7. Roots, fives, eights and the correct three and seven will play a lot of bass. Nothing wrong with just roots right at first. One note per lyric word. Ma-ry and lit-tle get two notes each as they are two syllable words. Sing the song - under your breath - with the vocalist so you know when to change chords and what tempo to use. If you have drums you two lock in together.

Major Scale Box. 
Code:
G|---2---|-------|---3---|---4---| 1st string
D|---6---|-------|---7---|---8---|
A|---3---|---4---|-------|---5---|
E|-------|---R---|-------|---2---|4th string

Fake chord on Cold, Cold Heart Invalid Link Removed That first A7- D is an intro, skip it if you want.
Bass playing a bass line to Cold, Cold Heart. Norah Jones - Cold Cold Heart - YouTube

Have fun.