A cappella blending

Harmonies. They can be the bane of your life if your voice isn’t in great shape. Especially in an A cappella setting because your voice might give a nice block harmony that “nails down a blackboard” vibe, prompting the other parts to do that quintessential “is that me?” wincing look.

Contemporary lead vocals are a whole different ball game. There’s quite a bit of flexibility when it comes to pitch accuracy as long as the emotion is there, and many lead vocalists’ technical imperfections are what we love so much about them. Let’s not change that.

Pitching in a harmony is non-negotiable. You have to basically be a singing cyborg, especially in modern, well produced pop. A flat or sharp pitch throws the whole arrangement, so you’re ruining it for everyone.
Also, where technical imperfections can be a welcome addition to a lead vocals tone and dynamic, in harmony you’re just going to kill the blend. And the MD will be on your case.

This is why your singer’s tool belt must be packing some serious features to be able to slot in to harmony like a ninja.

Here are few training principles that can help you develop the colour, accuracy and timing needed for harmony greatness:

Hoot and twang

Ask anyone about vocal blending and they will probably say “you have to match tone”. By definition, in this context, we take “tone” to mean: the quality (or colour) of the sound that is leaving the singers mouth. Scientifically, we are talking about the way the ear perceives the families of differing harmonics produced by a group of singers. In any solid fourpart acappella group, the singers will each be singing a different pitch. It’s easy to see – considering the fact that these unique notes also bring a whole spectrum of harmonics along for the ride – why harmony singing is really tricky and can often produce sounds that are, to put it bluntly, chaotic.

One way to seriously adjust the harmonics, and therefore the tone, is to change the vocal tract posture. Believe it or not, an easy way to do that is to sing like a yawny owl, or a witch. Often called “hoot” or “twang” respectively, these two vocal qualities sit at the extreme ends of the anatomical spectrum. An obvious change between the two is the dramatic movement of the larynx and tongue. For example, to produce a hooty sound, the larynx has to drop. The larynx rises and the tongue flattens and widens when we attempt to “twang it up”. It’s clear that the singer needs serious control of all of these physical changes to be a vocal tone master and use the right amount of each quality to complement the final sound.

Voice teachers often use these sounds as vocal development tools. For hooty you can play around with the vowel shapes “awe” or “oh” in what would be perceived as an “over-the-top” classical sound, to understand what it feels like at the extreme. For the “witchy” feel, you can use the words “nay” or “nehnehneh”, combined with pretending to be an irritating playground bully. It’s your job, and the job of your fellow singers, to work on just how much hoot or twang, compared to “normal”, is required to blend well together sound.

Clear onsets

We’ve already got a good win under our belt if we can match tone, but the block harmony could still sound really amateur if the timing of the onsets and consonants are all over the place. Onset you say? That’s the start of any note or phrase. For many singers the onset can be sluggish and lacking conviction, resulting in a messy harmoniser.

Practising on sets helps to develop quicker reaction times with clearer sounds as a result. The silent “H” is a great tool to develop the union of the onset, and offset, also called “valving”. Using any fairly low range scale or exercise initially (a major five tone scale, for example), create a belly-type laugh – a bit like the bearded fellow in a red suit.

Many singers prefer to use “HA” or “HEE”, but make sure for now that the “H” is more of a silent one. Start at a slow speed (about 90bpm) and perform the exercise. You’ll notice the activity in your belly as your breathing apparatus responds to the closing and opening of your vocal cords, which is the valving action we mentioned earlier.

Take care to create a consistent tempo, tone and sound between each repetition and proceed to change key up and down. When you feel consistent, it’s time to up the tempo gradually until you reach a high speed. How fast? As fast as possible without sacrificing the definition and clarity of the laugh. Stay at that speed until you’re a boss, and then increase the tempo again. This is amazing for staccato training in general, which is something singers really struggle with in the beginning.

Say what?

That’s a bad joke for diction issues. Sorry about that. This one’s fairly easy though; google “singing tongue twisters”. There are, like, a million, and they do have value. CLICK HERE to view as good a page as any.

It’s great to pick a few that have a wide variety of consonants, from plosives to aspirates and everything in between. As above, the same care should be taken on clarity and pronunciation, and only go as fast as you can clearly say the tongue twister, challenging yourself with tempo once you’re consistent.

Like a lot of singers, even when your diction is down your musical timing might be horrendous. Any syncopated line or odd timing might leave you with that guilty look on your face again. Nail this with basic rhythm training, possibly from a drum teacher or a music theory teacher who can show you the way of rhythms and time signatures. It’ll soon fall into place.


Some people call this “breathy”, some people call this “clean”. However you want to say it, it is important to separate the vocal cords, to approximate the vocal cords, as these vocal qualities can have a profound effect on the overall harmony sound.

Most people are sure to know the difference between being breathy or not and teachers will often work towards eradicating breathiness in the quest for technical efficiency. If you’re not breathy by nature, you can experience what it’s like to sing “breathy” by simply whispering or adding a slight “h” to the beginning of everything you sing. Unlike the onset, it’s a normal airy “H” and not a silent one. Exercises to get that breathy sound might also be aspirate consonant and vowel combos like “FOO” or “SHOW”.

Big red warning: being “breathy” is a vocal style that can also have a profound effect on the vocal health of the singer, so use it cautiously. Consider reducing airflow when approaching this.


It’s very important to have vibrato when you’re an all-rounder, and it’s equally important to be able to stop it from fluttering in on everything. We won’t go into the ins and outs of vibrato in full, but if you don’t have this semi-voluntary phenomenon then try these quick solutions to train it.

  • Cry: some singers are a whisker away from achieving the semi-involuntary phenomenon of vibrato. The upset “cry” quality on a voice can often drag it out of you quickly, allowing you to experience it and develop it. Try using the cry sound on words like “NO” or “GO”, sustaining a single note and relaxing into vibrato as you do it. This can often be more successful in the middle of the range, so for guys that could be between G3 and E4, and girls possibly between C4 and G4.
  • Swingin’. Try the same exercise as above, but before you sustain and find vibrato toggle between your original note and a whole tone above, like a little trill. This toggle before you sustain may be enough to get your vibrato swinging.
  • Make it happen. If you’re literally devoid of vibrato, some time spent making it manually is in order. Find your solar plexus take a good belly breath, and as you hold a note press firmly and quickly into the solar plexus a few times with rigid fingers.

You’ll notice the pitch and loudness of your voice “jump” with every press. As weird as this might feel, we can use this manual air pressure spike to train vibrato. All you have to do is press at the same rate of a typical vibrato, around six per second, while you sustain for four beats or so. Repeat, repeat, repeat. Your vocal muscles will (hopefully) begin to adopt the oscillation of pitch you’re stimulating with your fingers, and suddenly vibrato may appear on the end of notes. It’s usually out of the blue, so keep your ears peeled.

Equally, erasing vibrato is really important in harmony blending. Those with vibrato feel like it’s uncontrollable or impossible to erase. News flash: It’s not. If you don’t vibrato in speech, which is basically everyone, then you have control. Experience this by calling out to your imaginary mate with a long, single note “HEEEEEEEEY” as if they were upstairs. Remember, this is not singing. This is getting someone’s attention.

Hold the note for four seconds, and you’ll experience sustaining without vibrato. It’s not as “rocket science” as you think. Having the musical sensitivity and control to sustain a note without vibrato, and then allowing it to come in at the directed moment is what will make you stand out as a cracking backing vocalist.

The final word

As if harmonies weren’t hard enough already, we have to actually blend as well. Humph. It’s not enough to just sing the notes, which is what many novice and amateur choirs are focused on. That amazingly crisp and rewarding sound comes from the blend, and the tighter that blend the more wow factor there is for everyone. It starts with a little awareness of what’s available to you, and knowing how to actually find, experience and develop those options well.


Chris Johnson and Steve Giles are both experienced vocal coaches working in Southampton and London. They are with the Vocology In Practice teacher network and specialise in training clients in advanced vocal technique, style and improvisation. They are co-founders and presenters of the popular iTunes singer’s interest podcast The Naked Vocalist. As well as coaching and podcasting they are also in-demand performers and manage their own successful soul acts.