Warm-ups are an intriguing element in a choral rehearsal. First of all, they are not strictly speaking necessary as most singers will sing just fine even without vocalising. Secondly, some singers seem unreasonably dependent on them, while others could not care less. Thirdly, most choral conductors I know, including myself, often find themselves anything but enthusiastic at the thought of beginning yet another warm-up.
There are three possibilities: no warm-up; a warm-up for only those who desire it; and a warm-up for the whole choir. I will discuss only the last alternative here, but I feel it is important to realise that a warm-up is not a necessity. If you do have a warm-up for the whole choir, it needs to have a purpose. And here we come to building sound.
It would be naïve to assume that you can build the sound of a choir just through vocalising, but it can be an important building block. This is why I believe the warm-up should in the main be the duty of the conductor of the choir, unless it is run by a vocal coach who is present throughout the rehearsals. The idea here is that the warm-up should be a cohesive part of the rehearsal and the ideals of the warm-up should flow into the repertoire. This way a warm-up can be a central element of building a choral sound.
Whatever your sound and singing ideal is, the warm-up should reflect it. For me, central qualities in the sound and the singing are a certain ease of voice production and an energetic and full, yet light (as in, not heavy) sound. This means I work with concepts such as flow, freedom, energy and light and my guideline could be the the guidance of the great tenor Alfredo Kraus: every singer should always aim to sing as lyrically as possible. If your ideal is darker and stronger than mine, the following exercises might not work ideally for you. But they might, so do read on.
I begin my warm-ups with a short session (a few minutes) that focuses on the body. A few dynamic stretches (through movement) to relax the shoulder, neck and jaw areas and get the breath flowing deeper. Unless it is early morning, the aim is not so much in warming up the body as getting the singers to become aware of their bodies, calm their minds down and prepare them both physically and mentally for the rehearsal.
The first singing I normally do in a warm-up consists of trilled or voiced consonants (lip trill, rolled r, m, ng, n, even z). Especially valuable are the lip (a succession of p’s) and tongue trills (rolled r). This is firstly because the tremulation is in itself relaxing; secondly they create a natural and active airflow; and thirdly, because they do not really feel like serious singing, singers do not bring the baggage of vocal bad habits to the exercises. I use simple and fairly swift runs (5-4-3-2-1-2-3-4-5-4-3-2-1 or 8-5-3-1-3-5-8-5-3-1). I prefer high to low to activate the head voice or light register, but low to high can also be used (1-2-3-4-5-4-3-2-1). Make sure the exercises are began (the attack) in a light manner with no accent at the onset. We are looking for ease and steady airflow at this point of the warm-up.
Moving on to vowels, which are the key to good singing and a good choral sound, I try to build a bridge between the exercises. If I have used a rolled r first, the next step is the same exercise either begun with an r (rah, for example) or even changing to the vowel in mid-exercise. This helps to carry over the good effects of the first exercises into vowels (airflow, lightness, ease).
My second set of exercises is aimed at vowel colours and unifying vowels. The progression of Italian cardinal vowels from open to closed and back (a-e-i-u-o) or vice versa (i-e-a-o-u) or some variant of this sequence (u-o-a-e-i) is at the heart of this phase. Ideally, I try to find a combination of the space of the open vowels and the forward sound of the closed vowels to somewhat be heard in all vowels. For me, imagining that the differences between the vowels, and especially how they are produced, are as small as possible, works well. I have of late used the concept of the narrow road: open vowels work better for me if they open via the closed vowels (u->a, o / i->e, a). Singing almost entirely happens on stretched-out vowels and the quality and balance of these vowels is central to the sound of the choir.
From these runs of vowels I normally move on to a staccato exercise. This can be a simple [a] on a 1-3-5-8-5-3-1 or a combination of vowels (for example, [i]-[a]; [u]-[a] or [a]-[u], changing the vowel on the top note) or either of these solutions combined with a legato phrase on the same notes without a pause in between. Staccatos are brilliant in that they almost force a relaxation between notes and teach singers to control sub-glottal pressure. Make sure the attacks on each note are light and slim. I use the punch line ‘get rid of the rubbish’ around the note. If you listen closely, you will notice that there is a great deal of extra sound around the note. Strive for a clear, simple sound and the staccato exercises will be of most use. Because of the way staccato stops singers from pressing the voice, you can use it for lightening heavier legato exercises or lines in the music. Just have the singers sing the exercise or line a few times in staccato and ask them to retain the same character in the legato version – it should become more fluent and less pressured.
Another simple exercise with the same kind of remedial power as the staccato, is glissando. Glissandos come naturally to most and make register changes almost nonexistent. They also tend to lighten the voice at the top and make reaching high notes easier. Use glissandos as an preparation for a legato exercise that reaches upwards or to make a tough phrase easier to perform in the music.
After the staccato exercises, I move on to exercises that use nimble ‘tonguing’: fast-moving exercises with quick text activate and relax the tongue. A few favourites: vi-di or le-re (1-2-3-4-5-4-3-2-1); ‘there’, as in English, (5-8-5-3-1) with the tip of tongue out of the mouth all the time. In these, or any other articulation exercises, try to find a combination of loose, free vowels (phonation) and precise, small and active consonants (articulation). I think this is a very important distinction. Many singers try to form vowels with their mouths or try to tie the vowels to the consonants. To understand this thought, try ‘vidi’, for example, with an emphasis on the v, which leads to a tightening of the base of the tongue and the jaw, and then with an emphasis on the freely pronounced [i] – you will notice that the consonant becomes a smaller event that simply interrupts the vowel line for the shortest of times and the jaw and tongue remain relaxed.
After this sequence of exercises, we should have a relaxed, energetic and well-placed (by placement here I simply mean that the sensation of the singer is one of the voice sitting nicely and effortlessly forward and up) voice flow and are ready for singing. I find it good to do one exercise that comes very close to ‘proper’ singing. i,e. an exercise that is reminiscent of a phrase with text. There are tons of these, for example: https://www.youtube.com/watch?v=1hmqR8Iln70. I like to keep it fairly simple with the focus on singing really beautifully and freely. After this, the choir should be prepared for the first song from your repertoire. It is preferable to start with something they already know to ensure that what you have built during the warm-up can be used in the choral singing.
To create a bit of variation in warm-ups, rather than vary the exercises each time, I tend to use other tricks. For example, in the staccato 1-3-5-8-5-3-1, ask the singers to form pairs and stand face-to-face. Then ask them to touch hands, with one person palms upwards and the other palms down on the first person’s hands. Then while singing, the one with the hands on top pushes down gently, and the one with hands below raises them gently. After each exercise, change hand positions. While the hand movement may help in finding a little bit of support for the voice, the main idea is to make the singers forget they are singing – and create a feeling of togetherness in the choir (you can even have them change partners between each exercise). Other ways of changing the focus of the singers are just having them sing face-to-face (without the hand procedure) or back to back (touching). People tend to sing a lot better when they are singing this way. You can also just use simple movements to enhance the warm-up: ballet-like hand movements during an exercise; bending down whilst singing upwards; dropping the knees on the highest note of an exercise; stretching an imaginary rubber band; or even just walking around the room nodding a ‘hi’ or shaking the hands of the other singers whilst singing. And a great way to end the warm-up is to make long cluster chord by asking the singers to stop on any note of their choice of an exercise like the ‘bella signora’ in the video clip.
For me, the warm-up is mainly about establishing disciplines and reminding the singers of how one sings in this choir. There are choral traditions in which the warm-up is focused much more to listening, tuning and intonation. Many conductors like to use material from the repertoire in the warm-up exercises. My view is closer to vocalisation during a singing lesson. This tendency comes from my strong belief that intonation problems are normally due to problems in singing. If you manage to improve the way people sing, you will find the intonation improving.