This is a wide and as yet very poorly represented issue. Didgeridoo healing is the use of didgeridoo sound to heal people (and animals). The didgeridoo is an instrument that produces low frequency sound that we can hear and actual vibrations that we can feel, especially if the end of the didgeridoo is placed close to the body.

The image on the right plots the frequencies against the relative magnitude of the sound of a didgeridoo. As you can see the strongest frequencies of a typical didj are in the 50-200 Hertz range (the two big spikes on the left) with several harmonics going up to about 1000Hertz. What is interesting is that the didj also seems to produce near infra-sound as is indicated by the small spike near 0 Hertz, especially if you consider that our brain waves are in the 2-20 hertz range.

The low frequencies have a noticeable effect on living tissue. I am not aware of any studies of how the sound vibrations affect our tissue and organs (if you know of any, please let me know) but many people have actually experienced definite healing effects of the didgeridoo (see also http://www.didjshop.com.au/effects_comments.htm).

Aboriginal elders have shared with me that the didgeridoo was played near sick people to help them heal, although I have not heard of any accounts of the didj being played directly onto the body in Aboriginal culture.

So there is plenty of circumstantial evidence that the low vibrations of the didj have a healing influence on our bodies.

How to use the didgeridoo for Healing

There are several aspects and possibilities to the use of the didgeridoo in sound healing:

• The effects on the didgeridoo player
• The effects on people listening to a didgeridoo
• Playing the didgeridoo with it's end being held by the recipient
• Moving the didgeridoo over the body of the recipient while playing

The effects on the didgeridoo player

Much of the benefits of playing the didj is probably due to circular breathing as well as simply breathing more than usual. In order to play didgeridoo one has to breathe a lot. The more you breathe the better your didj playing gets. Since most people normally breathe very shallow the extra amount of air circulating through the lungs in itself is beneficial.

There is no doubt that breathing is one of the most important aspects to our health.
We also use breath to control our emotions - when we are scared we breathe in but we hold that breath and do not let it out. We do the same if we experience pain or anger and do not want to show those emotions. We control our emotions by controlling and holding our breath in.
This is how those emotions become locked up in our bodies and eventually lead to dis-ease. In today's society we are actually encouraged by social norms to suppress our emotions which makes the situation worse.
Playing the didgeridoo forces the player to push air out of the lungs - a reversal of the un-healthy pattern described above.

There is some evidence that cancer is often associated with low oxygen levels in tissue and other evidence that asthma sufferers emphasise the in-breath but do not allow the air to go back out in a relaxed way. We have heard anecdotal evidence that didj playing has vastly improved those afflictions (as well as several others) for some people.

If you play the didgeridoo for longer than half an hour, you are likely to go into a trance like state. It is as if your brainwaves go into alpha state. Most people report becoming very relaxed and yet very aware, feeling at rest and yet being energised. 
This is very similar to the state advanced meditators describe. This relaxation, centring and energising are obviously very beneficial for the player..

The effects on people listening to a didgeridoo

For anyone to be in the same space as a didgeridoo being played is usually a healing experience, even though many people would not even be aware of it.. Most people report that they feel relaxed and yet energised when listening to the didgeridoo being played.

Here are some more comments people gave when asked for their first experience of didgeridoo sound: deeply touching, in tune with the world, takes away from thinking, awe inspiring, magical, feels like a voice from the earth, ancient, haunting, powerful, primal, other worldly, mesmerizing, calming, enchanting, soothing, mystical, hypnotic, relaxing, earthly feeling, primordial.

You will enhance these feelings if you avoid fast changes in rhythm and loud vocals and instead concentrate on harmonics and overtones.

Listening to the didj seems to awaken deep and ancient feelings creating emotions within us which are soothing and healing, especially the deep relaxation the didj allows people to experience. There is no doubt that listening to the didj is a very effective treatment for stress and many of our regular visitors use the didj to wind down after a stressful day at work. 
So just playing the didj in the same space as other people is healing for those people. In fact I have been told by a well-known Aboriginal elder that they used to play the didj near sick people to help them heal.

The stress relieving effect of the didj can even be achieved by listening to didj recordings, especially if they are didj only CD's or have very few other instruments.

Playing the didgeridoo with it's end being held by the recipient

I like to call the didgeridoo a psychic vacuum cleaner except that it's rather a psychic blower. It seems to dissipate tensions, stress and any negative energies stuck anywhere in the body and to harmonise the energy.

Didgeridoo healing is also called vibrational healing since the recipient can actually feel the vibrations in his/her body which are caused by the low frequency sound of the didgeridoo. Interestingly ESA (the European Space Agency) is currently investigating the beneficial effect of vibrations on bone, muscle and hormone function for long space travel. I would love to see a scientific study into the effect of didj vibrations on the body and I would bet that beneficial effects would be found.

Playing the didj with it's end being held by the recipient is a good introduction for anyone to didj healing. Giving the recipient control about where and how close they want the sound directed to their body helps to relax people and makes the experience less threatening.
Ask the recipient to sit cross-legged on the floor or on a chair and you do the same opposite them so there is just enough space for the didj between the two of you..
Get the recipient to hold the end of the didj. This allows him/her to direct the sound and vibrations to where they want. You will need to clarify that they do not hold the didj too close to their body (less then 2-3cm or 1") as it might stop the sound from coming out. They also need to be aware not to move too fast or extreme as your mouth is attached to the other end of the didj.

A nice variant on this healing modality is two people giving each other didj healing. You sit again opposite each other and with one hand you hold the top of your own didj while with the other you hold the bottom end of the other didj.

Please also see the tips further down.

Moving the didgeridoo over the body of the recipient while playing

This, in my experience, is the strongest and most versatile way to provide a healing experience for the recipient. In order to do this you need a fairly light didgeridoo which preferably is of very good clarity and resonance. These sort of didgeridoos we classify as Healing Didjes.
I do not recommend you attempt this kind of healing session until you can circular breathe comfortably.

Ask the recipient to lay on a thin mattress or rug on the floor (it is best they have only light, loose clothing if any).
I usually start my sessions with the recipient on their belly and work on their back first as this seems to be less invasive for people. I like to begin playing the didgeridoo well away from the recipient and move around him/her pointing the didj away from their body just to fill the room/area with didj sound.
Then I might do another circle around the recipient with the didj pointed towards him/her but at least a couple of feet (~1/2 meter) away.
It is a very nice experience for the recipient to hear the didj sound circling. I sometimes stand fairly close to the recipient but raise the didj to be horizontal and then I slowly turn while playing. This projects the sound into a big circle providing full surround sound to the listener.

The feet are usually the body part I approach and give a good sound bath first - the soles of the feet are well accessible if the person lays on their belly. Approaching the feet first is less threatening than starting with the belly or the head.
You can hold the end of the didj an inch or two (3-5cm) away from the skin which is quite close. You might not want to be that close all the time, but you can certainly get that close.
After the feet you can slowly work up the legs, the buttocks and the back to the shoulders and then down the arms.
One really nice move is to go up one leg, say the left one, cross over the torso to the right shoulder, come down the right arm and then go to the right foot, up the right leg over to the left shoulder and down the left arm and so on. I call it the 'infinity loop'.
You can either just move the didj slowly and steadily over the body or you can move it in small circles to cover a wider area as you move up or down the body.

When you do a didj healing session trust your own feelings. You might be drawn to a certain area of the recipients body or feel like playing a didj of a certain musical key, you might feel like playing fast on one body part and slow on another. Don't question these urges, just follow them and trust the process.
At the end of a session I advise you leave the recipient alone for a few minutes to give them time to come back from their experience. If they do not come back after five to ten minutes, you can put some soft music on or gently touch them to bring them back.

There are no hard and fast rules, didj healing is intuitive, so use my suggestions only as an inspiration and enjoy...

Tips:

• Avoid sudden changes eg getting very close very fast and piercing vocals; if you need to stop, fade out and then start slowly rather than with a blast. Explore overtones and harmonics. You want to relax the recipient, not scare them out of their wits...
• You might want to put a bit of scent, etheric or essential oil or similar into the bottom of your didj before play. I like using AuraSoma or essential oils.. Spreading the scent around the recipient as you play can help to relax them. Make sure that you do not use scents that the recipient might not like so check with him/her first. (it also can help mask any bad breath you might have) Be sensitive if you are a smoker and freshen your breath before a session.
• Experiment with allowing periods of silence during the session. The silence not only gives you a break but it helps to deepen the experience. It's like allowing the sound to sink in and the recipient to relax and when you start again he/she can go even deeper.
• You can encourage the recipient to hum. Humming also creates vibrations in the body and can lead to a stronger experience for the recipient. Or/and you can ask the recipient to bring their awareness to their breath and direct their breath towards the areas where they feel the vibrations.
• If you are likely to have some of your spit running down the didj, cover the recipient with a thin blanket, so it can absorb any 'drips'
• Be gentle and humble in your attitude, it's the magic of the didj sound that does the healing and not you - at best you are a channel. Leave your ego behind as it will only get in the way

Read on:
Didgeridoo and Meditation