Phil (AIDA NZ president and one of the founders of the AFC) offered a session on equalising last night. While it was pitched as "Equalising 101" it was a very informative session and I learnt a bit.
Started with a "dry" discussion poolside talking through the mechanics of the outer ear, middle ear, eustachain tubes, inner ear, nasal cavity, soft palate, epiglotis, lungs etc. Next was a summary of the different equalising techniques and their pros and cons. Simplistically - Frenzell is the way to go, Valsalva sucks.
(Luckily I discovered I was using the Frenzell technique already)
Next topic was "mouthfill" and how / when to do it. Essentially you take a big gob of air from your lungs and hold it in your mouth (before you need it) for equalising. Most would probably do this round 15m. Then use your (full) cheeks to provide pressure for equalistion until you get to the point where Frenzell becomes practical again. If you master this then apparently it is possible to go deeper than most imagine (40 - 50m or even more).
After this it was time to get in the pool and split into two groups. 1st group focussed on practising Frenzell while head down (funny seeing feet hooked over the side of the pool and heads on the bottom). The guys in this group progressed really well - I think they all figured out Frenzell.
2nd group had a crack at exhale dives and practicing the technique to get a mouthfill and using cheeks to provide pressure for equalisation. This was an interesting exercise for me - I think I got there but need to try it in deeper water to really see.
Tonight Phil will be running "Equalising 201" in the lake where all of the above will be put into practice (10m - 20m dives with exhale etc. I think). I cannot make it so will have to get some of he others to give me an update later.