I’m having a surprisingly exciting time in terms of music theory. I finally sort of understand how scales, modes chords and chord progressions relate to each other, which is great. My burning question right now is how do you pick a key to work in when you’re writing music?
I’m getting the hang of where to send the progression once you’re in a key but how do you get to the start point at all?
Perhaps some deeply immersed professional composers have in mind a certain key for a certain musical composition… but at this stage just pick one and if you’re going to sing pick one that ends up matching your vocal melody.
Honestly, that makes as much sense as anything. Thanks!
@Dweebs12 Phoebe, music theory is exciting when you are learning theory you can apply. I’m glad you are enjoying it.
I have written occassionally. I tend to write on the piano. That’s the instrument I’ve played the longest to a decent standard. I’ve played in church a lot and have a good idea of where the song needs to be pitched for most singers to be able to sing. If I’m reaching the G below middle C, it’s too low. If I’m finding myself reaching the E an octave and 2 tones above middle C then it’s probably too high.
Once I’ve got that I’ll put it in a key that is easy for piano and guitar whilst still fitting in the range I think works for most people. So A,D, G,C. E or F if I have too, but I don’t find either of them that easy on guitar.
The most popular keys for guitar are C,A,G,E,D and their relative minors. Just so happens to be the same chords that make up the CAGED system.
Great advice already given, but I think no one yet mentioned to include chords that are easy to play for you ratzher than those that you have difficulties with and then that could also narrow down the selection.
At least me, I’m often starting to play around with patterns and chords and find some nice sounding chord progression + pattern/rhythm, then, when I’m not sure in what key those possibly three or four (or more…) found chords are in together, I look the chords in keys up in a big cheat sheet like this one… https://www.reddit.com/r/guitarlessons/comments/im0d2u/the_ultimate_cheat_sheet_v2/#lightbox
Great question!
Honestly, this answer is probably going to be a little different for every songwriter.
When I am writing, I’m often just playing around on the guitar until I stumble on something that I like the sound of. I’m not thinking of the theory behind it upfront most of the time. Once I get something I like, then I will focus more on figuring out the key/analyzing what I’ve written.
That said, there have been times that I started with the key upfront. I have two bands that I am a part of and write music with. For one of the bands, we all collectively decided on a key we wanted to write a song in and started there. The other example would be anytime I’m writing anything using a mode. I like to choose my key upfront for those.
I don’t really think there is a set method- everyone works differently. If it’s easier for you to limit yourself to one key to start, then just pick a key and go for it!
Have fun!
Good question.
This was a more important consideration in the past, before equal temperament became the standard in Western music. Prior to the adoption of equal temperament, different keys had more distinctive elements; equal temperament homogenizes the aural qualities of the various keys in a way something like just temperament does not. A composer working in just temperament would want to consider the distinctive aural qualities of the keys; a composer working in equal temperament has no need to do this.
In a nutshell, if you’re composing in equal temperament (which is almost certainly the case for modern Western music in the rock/pop/country/dance/etc genres), one key will sound much the same as another. You don’t need to think about “distinctive aural qualities of a key” in equal temperament.
Instead, you can choose your key based on the desired instrumentation. Some instruments are better suited to certain keys. You could also favor one key over another based on ease of music engraving and reading, avoiding keys which complicate the sheet music with many sharps and flats.
Allied with a capo, you can play in any key whatever, using the chord shapes of a ‘guitar friendly’ key.
King capo Richard yeah I am busy with Romeo and Juliet without that capo I would be lost cheers Hec
I think this is far easier than it is being made out to be. An instrumental piece shouldn’t really matter, play in the key that you used to develop that particular musical movement/tone. If it is a song, choose the key that you are comfortable singing. When you play/sing cover songs, which one(s) seem easiest to sing or sound the best for your vocal abilities? From there learn your chords to a key:
There are tons of chords in a key charts on the interwebs.
Yeah, I do music theory, so i know my Keys to some extent, but the capo just comes in handy sometimes, like I say, Romeo is played like that because of the finger picking, I guess cheers Hec
I’m not sure anyone has made it difficult. A few people have answered the OP with how they select keys - that may or may not have value for Phoebe (the OP).
I agree with your answer, but it may be limiting in some cases. E.g. if Phoebe isn’t writing for her own voice. Most of the songs I’ve written have been written assuming I’m not going to be the one singing them. I need to be able to sing them so that I can record a demo, but I am cognisant whilst writing that my voice is pitched lower than where is comfortable for the majority of singers. Others will have other reasons why they pick the keys they do.
Hopefully this makes sense.
All the answers so far have been pretty helpful (thanks all!), and I’m glad I have options for picking a key. I probably won’t be writing specifically for my own voice for the time being, so it’ll be more down to picking something that works with the guitar and digging out my capo if I need to sing!
I was speaking to the OP directly, having to ask the question suggests a level of confusion. Easier doesn’t automatically suggest that things were difficult (or to what degree) to begin with. 
As for other singers/players, they can change the key to suit their vocal range, playing ability or tonal interest. Capo or swap chords as needed. No one should feel bound by a particular key, and the theory behind changing keys is rudimentary.
That’s the spirit!