Day 3, TFX vs D400 and G250
Three great dives today. More sunshine, moderate current, beautiful reefs. Palancar Caves was especially nice, with lots of glorious swimthru's. Yucab is showing stress, with the last three inches of every branching hard coral bleached white.
Today I compared the TFX with my old favorites. The D400 (tuned to 0.6") breathed like a dream. There was a slightly higher pitch to the inhalation sound, but no effort even while holding place in current. But breathing harder, I could sense the added exhalation resistance of the D400. It was of no concern, but I might have had a little concern if I were swimming for my life. Bubble dispersion was occasionally irritating compared with the TFX, but I'm so used to it with this reg that I wasn't as upset as I might have been. The D400 still represents the lightest breathing reg in existence after the TFX. I'll dive one until my rich grandmother buys me as many TFX's as I could ever use. Oh, yeah. I don't have a rich grandmother. Well, as soon as TFX diaphragms are available,
@James79 can make us a retainer to use them in our D's.
The G250 (tuned to 1.0") was like putting on an old shoe. Comfortable and easy breathing. Sharp inhalation wasn't as smooth as with the TFX, because I have an old original Graphite with a Venturi vane that's set in the shop and not easily diver adjustable. Since I keep it slightly detuned to reduce freeflows, simulated heavy breathing wasn't quite as smooth as the TFX. I would still take my old G250 to any depth, but I suspect the TFX might beat its performance at max gas density (132' on EAN28).
One small disappointment... the current had us holding position in one direction, while what we wanted to watch was occasionally behind us. As a result, we were repeatedly looking not only straight down, but more towards our feet. In this position, the TFX exhaust valve was slightly past vertical, and the mouthpiece pretty low. I'd repeatedly get a couple of moist drops on inhalation. It looks like this position is the one Achilles heel for this reg.
As a pleasant discovery however, when I mounted the TFX for diving as my octo, and put the mouthpiece holder in the PADI golden triangle so that the diaphragm was facing the water, I still didn't get a freeflow on giant stride. I had placed the Venturi lever on Minimum, but that's the only adjustment I made. So being tuned hot without an adjustment knob is not a problem when using the TFX as an octo. Worn as a necklace, the reg doesn't hang with the diaphragm facing the water, so it never freeflowed there either.
Another irritation: my new TFX first stage is now very quietly screeching/whining/singing with every few breaths. Just like the Scubapro Mk25, I suspect that the thin spring that's holding the o-ring stack in place is vibrating with high pressure gas flow. I'll take it apart and see if bowing that spring helps.