Balanced vs unbalanced 2nd's

[redacted]

One nice thing about scubapro is they don't have a lot of unnecessary parts. So all the balanced barrel poppets and all the R-series (including the Air2 and grand daddy 108) use the same spring, 01-020-216. They just crank it down more with the R-series.

Pics are the paddle and the key are in my photo gallery. The key is inserted into the "S" and turned about 1/8th turn, pictured installed in a 108.

I'm having problems loading the pic. I'll try again tomorrow.

I think I have some pictures.

 

[scubafanatic]

Interesting question. My experience is it is just hype. I'm sort of a "throw back" I guess, but all things being equal I prefer "simple" over more "complex" designs. But there are some current balanced adjustable 2nd's out there I'd love to try....

I've taken unbalanced classic downstream 2nd's quite deep. If properly tuned they've worked just fine. Better than fine actually

If you have a balanced 1st stage, there should be no change in IP to be concerned with.

I think the main "advantages" a balanced adjustable 2nd stage brings to the table are the ability to tune the regulator a little closer to freeflow, and more important, the ability to DE-tune the regulator in case it does freeflow a little , and the ability to use a lighter spring. The ability to detune (strong current, etc) I think would be the biggest selling point for me.

I currently dive both balanced adjustable (Zeagle Flathead) and unbalanced classic downstream (Mares Abyss) regs.... well the Mares is slightly different from a regular classic downstream due to it's design that optimizes venturi effect... Anyway, despite the Zeagle Flathead being a fantastic reg, I seem to prefer the way the Mares breaths, and usually use the Zeagle on a stage.

Best wishes.

.....I've pretty much retired (as in, keeping them in sealed/climate-controlled room in large plastic bins....as 'reserve' regs) my Mares regs because I came to find I preferred the ability to detune--heading into a current/turn back up for high demand situations--my 2nd stages...also, having diver-adjustable 2nd stages means I can compensate in the field for variations in the setting of cracking pressure by service techs. So, I dive/own various diver-adjustable balanced 2nd-stage regs...as well as various non-diver-adjustable un-balanced 2nd-stage regs. The one thing I don't own is a non-diver adjustable...balanced 2nd-stage...so I can't comment on that configuration. I will say that my 2 Atomics (M1 + T2) and my 2 Apeks XTX 200's, are awesome regs, both are, of course, balanced/diver adjustable 2nd-stages. I'd say my 'best' Mares reg is a very nice RUBY, but I haven't dove it in a while...nothing at all wrong with it, reliable, always performed well, ...just transitioned to my favored design these days..the adjustable 2nd-stage.

Honestly, overall, it is likely that the differences in overall reg design quality...and the differences in the quality/abilities/experience level of your chosen reg tech make a bigger difference in how a reg performs than does the single factor/element of whether or not you have a balanced or non-balanced 2nd-stage design.