Young beginner bands - without much experience - are perhaps inclined to make a mistake when first putting a set list of songs (or covers) together to work on. Basically, they sometimes have their priorities wrong in that they don't always prioritise the singer's ability and willingness to sing the material being considered. It could be an afterthought by which time they come to realise that a given song is just not workable...or a change of key is going to spoil the sound of the song. Admittedly, this often happens when a singer is still the missing key componenent: either because no one in the existing band has yet volunteered to take care of vocal duties or because it is not yet known who has what vocal talents in the band; or because it hasn't been talked about; or because the band has decided that they need a singer to join them but don't yet have one in place.
But even if a singer is secured, it's not always they that gets to say what material is looked at. Put it down to band dynamics! But it's a big mistake - not to consider the singer! At some point, the band may come to realise their mistake; or in a worst case scenario, they soldier on anyway thinking that the singer will manage anyway.
The point is that the singer or vocalist should be the main consideration when choosing any song to practice and perform; assuming the band already has a vocalist. If an external singer is needed then it becomes pure guess work as to whether the chosen songs are going to work or not. Time and effort might be wasted in the interim.
The reason: the vocalist is the interpreter of any song; they sing the words and they directly communicate to the listener. Therefore they are the focus; with the other musicians creating sympathetic support. They are not the focus...not matter what they might think about their importance. And the most important thing to consider is credibility. When the singer sings the song, it must be credible; it must be convincing and it must effectively put across the intent of the song. If that does not come across then any amount of musical support will do the song no favours. I think the tendency might be for young musicians to forget that they are serving the song; rather than the song being a platform for their instrumental skills. It's the wrong perspective! So the most important thing of all is...effective communication with the audience or listener. And if the song is 'wrong' for the singer then it won't work!!!
So credibility has to do with putting a song across convincingly; the singer principally must be able to deliver the song's message in a way that the audience or listener understands; gets the message; feels the emotions implict in the song. How is it that the singer cannot sing a song credibly? Well, perhaps they cannot relate to what the song is about; the experiences and observations that the song speaks of. Or perhaps they don't sympathize with the perspective of the song writer. Perhaps they don't have a face that fits. You may laugh but sometimes the face matter; and it doesn't have to be a pretty face in order to fit; sometimes a real ugly face is a better fit. So...how the singer looks matters. It's all part of the credibility. Or perhaps the singer does relate to the song and would love to sing it, but their voice doesn't sound right. Imagine, if you will, a weak nasal vocal performing any of ACDC'S songs? No, it isn't going to work: what is needed is a bit of macho posturing, a voice that sounds like it's been dipped in drain cleaner or garggled with razor blades; the voice of Brian Johnson or his predecessor, Bon Scott. A pretty Folk voice is not going to cut it.
But there is also a question of the right key. Sometimes the original key is not right for the singer. Rather than doing themselves an injury, they need to change the key. But then, sometimes option is not going to work - some songs were built for specific keys; especially if they were written on guitars. A case in point is Stairway to Heaven by Led Zeppelin. Any key other then A minor is not going to work too well for the guitarist; let along anything else.
My advice would be to get to know the vocalist's capabilities and preferences really well. The band has to be built around them. Better still if there is more than one vocalist in a band; it presents choices! But beware of instrumentalists that decide they are going to give the vocals a shot. Heroic as that might seem, they are not always suitable. First, it is a question of where your head is at when performing. I would contend that instrumentalists often have their main focus on their instrument with vocals taking a paltry second place. If a singer cannot give focals their main attention then forget it. If you cannot play an instrument without having to think about it, then forget it! Singing or vocalising takes as much study as an instrument; something which instrumentalists are often oblivious to. It is not just a matter of opening your mouth and letting something come out! It deserves respect.
Ok, I hope I have given any young musicians reading this, something to think about. Happy hunting for your perfect vocalist.Don't ignore them!!!