Hi Nestor.
I have struggled with EQ since the dawn (of my diving ages) and since I mostly dive on vacations I can not work on it continuously.
But recently, on a freediving course (my third) things finally started changing.
I recently wrote a long email about my EQ issues and small successes to a friend and after a bit of editing, most of the content suits your OP as well.
So, here we go:
Yes, it is very, very important that you never push deeper if you have an EQ block.
Any instructor will tell you not "to ride the drum", not to go deeper hoping to EQ later. But many students are eager and put too much pressure on themselves and it back lashes.
You have to stop immediately and clear your ears. If you succeed and you are relaxed and have more air, then you can go back further down. I did that a lot the first few days on the course.
I had to turn head up to clear my EQ blocks around three times just to get to 15m. Then later, it got better and though I still blocked, I cleared the blocks faster and just by pushing my head back a little - as opposed to having to turn completely head up/feet down.
I now know of two divers in the last few weeks who popped a small hole in their eardrum because they did not stop in time (one on this course, one on a different location). Even if you don't perforate the drum, then pushing too far will just irritate your ears and often will make diving impossible for the rest of the day. That used to happen to me a lot.
Now, I never go deeper than my EQ permits. Doesn't matter if it is 2m, 12m, 20m or 30m. You HAVE to stop immediately if you don't EQ.
I think instructors, and especially good ones, are reluctant to say that a student have narrow tubes or other physiological challenges because it can become a bad excuse to not work on the EQ technique. And even if one do, that's just more the reason, you should work on your tech. That said, I, and my instructor, are beginning to think I belong to that category. Supposedly, I Frenzel and do a good job at it on land, but to pop (EQ), I feel like I need a lot more air and a lot more pressure than others.
But despite this, these things helped during the course and practice dives:
1). More time in the water
I was diving 12 days with one day off. I think my ears and E-tubes got more used to having to work all the time. BUT DON'T PUSH IT, never EQ too late! Better to just go back up. Always!
2). Better technique
Maybe my tubes are narrow, maybe they are not, but I do feel like I have to force more air through and with more power than most people. So, every day I practiced Frenzel on land. Maybe 100-200 times or more. My tongue got stronger and I may have gotten more air through the tubes at a higher pressure.
I even started putting my finger in my mouth to feel how my tongue was pressing against the roof of my mouth and with how much force. It looked like a grown-up baby and weird for sure but it was a good way of linking that muscle movement to my brain.
3). EQ often
I also EQ once on the surface and then very often for the first 10-15 meters. Once I started doing that (it took some time getting it right) that helped a lot down to 15m. I'd say at 15m, on my most smooth dives, I have probably EQed 15-20 times, maybe more. That takes practicing on your Frenzel and you can do that on land.
4). Go slow
I actually don't even duck dive because I don't want to go down too fast in the beginning and risk an early block. I just raise one fin in the air and pull slowly down on the rope. Trick is to go slow. The slower the better. Also, going slow relaxes you and you use less O2 this way.
(That said, and I am really debating whether to post this here or not, but here we go:
Something strange happens when I go faster - I actually EQ better… It is against everything logical and it's not the smart thing to do but I think it is a mental thing.
If I go down faster, I think my brain KNOWS it REALLY has to EQ so I subconsciously do a better job…
Your instructor may not let you do this and if you do it, you should REALLY STOP RIGHT AWAY IF YOU DON'T EQ. I can't stress this enough. When going down fast, it's dangerous if you don't clear because you risk damaging your drums much more easily. But if you hold on to the rope and grab it the second you have a block, then you will automatically turn around right away.
If you try this, then promise to be ready to stop right away in the event of a block!
I used this "high speed attempt" to prove to myself that it was not always as bad as I thought and then I would work on slowing down afterwards.)
4). Mucus!
I have sooo much snot in my skull, you have no idea. I blew my nose before each deeper dive and it helped a lot. If I didn't I would most often have an EQ block in vey shallow waters.
Also, each morning and each night I would use a modern "neti pot" and rinse my sinuses. Look up "nasal irrigation". On the advice of a fellow diver, I actually ended up bringing the bottle with salt water in the float and rinsing just before the deeper dives to make sure there was no snot in my sinuses at all. That really helped as well. In a pinch you can just snort salt water - I did that before bringing the bottle out to sea. If you want a bottle, then look for Nasopure as that one seals completely so that you can bring it on the float without losing the water inside it.
5). Sphera
As someone who like to spear and photograph under water, I have always been a bit against the Sphera mask cuz its peripheral vision is blurred and funky. After a while, I think the brain maps this and adjusts for it, so it's not bad at all. But while I am still not sure if I could spear and shoot pics with that mask it was one of the little things that def helped my EQ.
(BTW, keep an eye out for a new mask from SubGear. It will be very compressible like the Sphera but with real glass lenses and it fits a ton of different face shapes. The glasses bend independently which makes the mask more flexible - dunno if that will lead to funky vision too though.)
So, basically the combination of the above things helped a lot. The first few days, I struggled to get to 15m while at the end I was nearing 35m. Coming into the course hoping to start doing 20-25 without too many issues, needless to say I was a happy camper.
But now, I just dived in a 15m tank in China the other day and… I had blocks at the end of the day at 4m! So, it's a constant battle. And my Frenzel was not as good as in the Philippines. Practice, practice, practice!
Nestor, all this above refers to a rope and diving on a course, but the points still remain - and of course, you should really consider taking a course.
I have also had good experiences with a book by Federico Mana about EQing: "Equalization for Freediving". There's an Italian version as well.
It's very good, very technical but good to have as you get better.
Good luck with it all!