interesting comment from dive shop owner

[GJC]

I think that a smaller diaphragm may require more effort to breath, but I think that the manufacturers would never produce one small enough for you to start noticing it.

A larger diaphragm probably won't make a reg easier to breath. Double hose Royal Aquamasters have a huge diaphragm and the same first and second stage as your Conshelf. They don't breath easier.

I think other factors have more of an effect, such as:

Lever length
Second stage spring compression resistance
Friction of internal parts
Intermediate pressure changes
And other factors that I'm not remembering right now

The exact same parts in your Conshelf 21 were produced in Conshelf XIV regulators in the 1970s and a lot of them are still in use. They also continue to be produced as the Conshelf 14.

How a regulator is serviced and tuned has the biggest effect on how well it breaths.

 

[drk5036]

I admit - it is clever idea but this apparently wouldn't work - Apeks' first stage is over-balanced, would not be compatible with my Conshelf's 2-nd stage.


You are on the right track - I am very seriously considering this one!! But why "instead", the stock market has been good to me I can easily afford both

Guys, thanks for your input but no one addressed the crux of the matter - is there any truth in his statement that the diameter of the second stage has any impact on the "ease" of breathing?

Good idea! Buy them both, and get the old reg serviced and send it to me!

 

[AfterDark]

A larger surface area is more sensitive to pressure influences (a big button is easier to push than a small one kind of thing)
so yes a large diagram will respond quicker to inhalation effort due to the influence of ambient pressure on the large diagram.

I still use Scubapro MK5's and 156's converted from 109's and sold in the 1970's. All my years diving I've yet to find a better reg set. I've found plenty just as good and some not so good, but better no.

 

[JackOfDiamonds]

Sounds like he was being very honest with you and not just trying to make money off you.

I'd stick with them and support them as much as i could, they are very rare nowadays.

 

[Ben_3]

If you have extra bucks and want something new, then why not. Your shop owner seems nice enough not to just want to sell gear. The X4L is a great reg. It’s my reg set. Is it better than the other, probably not. Size and weight of the XL4 is great for travel.

 

[Hoyden]

I will say that I use a light weight travel reg when doing warm water vacation diving. It breathes fine... but while I was on my last trip, I set up my wife's gear and she travels with an old (although not old compared to your Conshelf) Zeagle Flathead V. Holy cow, it breathed so much better than my little bitty travel reg... there is definitely a trade off between size and awesomeness.

 

[lexvil]

The advice on the conshelf is sound, rebuild them but...

A larger diaphragm makes for a second stage that is easier to make a great breather but a modern smaller reg can be tuned to the same and maybe even better performance.

For travel lighter is better and for Truk you’ll want all of you essential gear with you as you travel, as in carry on, my checked bag and some gear got to spend a few extra days in Guam, I had in my carry on/personal bag my regulator (Atomic ST1) a set of SPGo fins (size 15 feet so fins matter) computer, etc. my freedom plate and 18 lb VDH wing didn’t get there for a few days so had to rent, the worst part was having my mask in the Eddy fin foot pocket and having to use a mask that was marginal but I still dove.

I can pack everything into a dive backpack made up of my backplate/wing all essential gear in a cylindrical dry bag held with the tank bands with fins strapped to the sides, I should have done it on that trip. With lighter stuff you can carry more with you. I now travel with an Atomic titanium reg and it can breath better than most things out there and in my checked bag a Zeagle F8 goes as back up.

Reliability is first priority but for travel weight matters.

 

[Michael Jastrzebski]

Many good comments, I appreciate.

so yes a large diagram will respond quicker to inhalation effort due to the influence of ambient pressure on the large diagram.

This is in fact exactly what he said ...

The X4L is a great reg. It’s my reg set. Is it better than the other, probably not.

As long as it is not noticeably "worse" I am OK with it, I have studied some reviews of regulators in scuba magazines and nowhere did I find a remark - buy "larger" regulators or you will notice the difference.

I'd stick with them and support them as much as i could, they are very rare nowadays.

You bet, I just got a new BC from them made by "Riptide". One problem with this dive shop is that they are not dealers for any well know brand (apart from wetsuits), he offered me the Legend regulator which
would be without any Aqualung labels (he claims he gets them directly from manufacturers), with warranty. He claims there are only two locations (rooms) in the world where all regs are actually made and
he gets them in 'generic' format, his prices are incredible, I would have to pay for this Legend "equivalent" around $300. The only dive computer he carries is DeepBlu. His dive shop is in a rather rougher part of town and by its outside appearance could be
easily mistaken to be a drug dealing place but he's got a real dedicated scuba clientele and great reputation.

 

[runsongas]

sounds like jim steele alright. nothing wrong with the conshelf, but i personally prefer a balanced 2nd for deeper dives like you will have in chuuk.

 

[Michael Jastrzebski]

sounds like jim steele alright.

you got it!!