While we may like to pretend otherwise, there are pragmatic aspects to writing music. One of those un-artsy but important things that musicians have to consider is time. For example, a typical piano arrangement written for church these days is in the range of of two minutes. That has changed a lot over the past few decades by the way. I am not saying whether that change is for the better or worse (I tend to be ambivalent) but I will say that if you plan on playing an offertory more than three minutes, it had better be pretty good. You might also check for a trapdoor under the piano bench before you attempt that. 😉
Shorter offertories take pressure off writers in some ways and here is why. Inexperienced writers usually do better with shorter pieces of music for a rather obvious reason: shorter pieces require fewer ideas and less development. Frankly, it is hard to get even one idea into two minutes. Ever try to develop a power ballad in two minutes? Forget it.
That being said, not all pieces are two minutes and sometimes we all struggle with finding ideas to get a song to the length it needs to be. One of the things I often see writers do to elongate a piece is adding another song (or two), turning it into a medley. I have done it myself.
This came up in our recent master class and I discussed it for a bit. We heard a really nice piece that was a medley of two songs. The songs fit together just fine. There was nothing at all wrong with what the writer did. However, I took the opportunity to make a point about writing and it is this: if you decide to turn an arrangement into a medley, you need to have a strong musical reason for doing so that goes beyond just extending the length of the song.
I will elaborate on that in a second but let me tell you two medley traps to watch out for:
No musical continuity between the two songs.
Sometimes, the ideas between the songs are so disjointed that the arrangement feels like two distinct songs that have been clumsily connected together. Every arrangement you do should have a planned arc or storyline and any additional tunes you add should done in a way that supports the arc. For example, if your form is a power ballad, when you bring in your new song, it should feel like it fits naturally in the arc of a power ballad. In other words, you should probably bring it with more intensity than the previous section. It should also borrow and develop musical elements that existed in the previous section.
Depending on the change of melody in itself for diversity/development.
Sometimes I hear a few songs combined together into a medley and there is really no difference in texture or any other musical elements throughout the medley. It feels like the writer is depending solely on song change itself to provide the development of the piece. That really doesn’t work so well. If you have tune changes, you still need to have an underlying development going on that sits on top of those songs and creates a polished piece that stands cohesively with its own distinct arc.
You might get the idea that I am not too big on medleys at the moment and you would be right, at least at this point of my life. That is especially true if you are talking about pieces in the 2-3 minute range. If you are writing in that time range, I really can’t imagine many cases where you should turn a piece into a medley.
This is not a right or wrong thing. It is probably just a preference thing. The bottom line is this: if you are using a medley because of a musical reason, go for it. However, if you are falling into the trap of using a medley just to make a piece longer, you probably should try to stick with one tune and work harder on coming up with a plan for developing it.