What's the best reg for me?

[halocline]

I've numbered and edited your points because I still don;t know how to do the multiple quotes. My replies are numbered as well.

This is what I have discovered...
1.The amount of energy your regulator requires to move each liter of air is called work of breathing (WOB). Lower work of breathing means lower effort required to breathe and increased comfort and safety during a dive.

2. The size and force of the spring is considerably less than that used in a standard demand valve, leading to less effort required by the diver to open the valve and initiate air flow.

3. The only problem with the pneumatic systems is that they deliver pretty much the same air at depth as in shallow dives therefore you can breathe up to 50% more air with a pneumatically balanced system.

4. The Delta 4 has diaphrams made of polycarbonate not steel, and I've heard the second stage is a bit noisy and gets a bit wet when inverted. Other than that I think it would be a great choice, besides Weaserm99 is a divemaster and he likes them.

1. Correct, except WOB has basically nothing to with safety. Reliability is what determines safety.

2. Remember that you're not just working against the spring, but also against the air in the balance chamber. The only difference is that with a balanced reg, when the valve does open, the IP drops, which means the air pressure in the balance chamber drops a little, making it theoretically easier to keep the valve open. Your argument here sounds just like it was pulled from some ad copy for a balanced reg.

3. This a totally false statement, I'm not even sure exactly what you're trying to say. All regs deliver air at ambient pressure, which means higher pressure as you go deeper. They would not work otherwise. Having a balanced reg will not increase your air consumption.

4. Steel diaphragm? not likely! You must mean something else.

 

[mempilot]

Thanks for your reply, but I don't think so. Apeks is Apeks. Aqualung are just the (US) distributor, just like they are for Suunto. (I think !!!!!!). Feel free to correct me.

They've been sharing design and parts for many years. Take a look at the Legend first stage. The parts and case are interchangeable with the XTX200. Other than cosmetics, the 2nds are identical as well.

I may be wrong, but I believe Apeks is now under the conglomerate umbrella that is Aqua Lung, as is Sea Quest.

 

[anzac65]

They've been sharing design and parts for many years. Take a look at the Legend first stage. The parts and case are interchangeable with the XTX200. Other than cosmetics, the 2nds are identical as well.

I may be wrong, but I believe Apeks is now under the conglomerate umbrella that is Aqua Lung, as is Sea Quest.

Okay, thanks for that Mempilot. I guess if Aqualung are cheaper than Apeks that makes them a good buy.

 

[deepblueme]

WOB Does have ALOT to do with saftey.

Never hear of divers panicing due to not getting enough air(over breathing or a hard breather Reg)?

I have seen it many times.
One student during an air share drill in 40 feet told me to surface after she had switched back to her reg.
When we got up she said there was something wrong with her reg a MK2/R190 I had just tuned.
We had we had been buddy breathing off my MK20/G250.
Her reg was working fine till she took some breaths off of mine with a higher flow rate and easier cracking effort(WOB).

 

[mempilot]

Okay, thanks for that Mempilot. I guess if Aqualung are cheaper than Apeks that makes them a good buy.

Apeks ATX200
List: $720 Discount: $520

AquaLung Legend
List: $655 Discount: $485

Your are right, the Legend is about 7-9% cheaper and both are an exceptional buy compared to other regs on the market. Like you, I prefer the Apeks, but the parts kits are the same and the only real difference other than cosmetics is the metal adjustment knob on the Apeks vs plastic on the Aqualung. I'm not too keen on the gold bling on the Legend.

 

[Zoomer]

I'm looking for a new reg to replace my old Mares. Here is a background of what I want and how I dive.

• I will do warm water diving only
• Diaphram only
• My max price is $650 for the reg (I will buy the octo separately)
• No Atomic (I will forget and dunk my reg and that would ruin the Atomic's first stage)
• Preferably not pneumatic
• Needs to be durable
• Preferably serviceable in Mexico
• I will be doing 1-2 dives a day, 6 days a week, for 6-8 weeks at a time
• Needs to be an easy breather

The reg I am leaning towards is the Oceanic Delta 4 but I have also heard good things about some Apex's.

Oceanic Delta 4 FDX10 with DVT...

 

[Luis H]

What I mean by not pneumatic is a part in the second stage. I'm not entirely sure what it is called but it is a lever that is in the second stage that holds back the air pressure that is coming at it at 150 pounds. When you inhale, this opens up the spring and allows air into your regulator. When this part is pneumatically made, it requires only 5 pounds to open it, but, allows in a predetermined amount of air in. This makes it impossible to take shallow breathes as the predetermined amount of air will be released anyways. This Aeris has this pneumatic feature.

When you are saying “pneumatic” it sound like you are kind of referring to a pneumatically balanced second stage, but you either misunderstood how it really works or the person who tried to explain it to you didn’t do a good job at explaining it.

As Couv said, all regulators are pneumatic. If you follow some of the other links that Couv provided, it should have some decent explanation of how it works.

The Oceanic you are looking at does not have a pneumatically balanced second stage (as per the specs on their web site) it has a mechanically balanced second stage.

A mechanically balanced second is a bit simpler and it may work a bit better as a pressure relieve valve in the case of a first stage malfunction with an IP rising. The pneumatically balanced will still vent, but since it is not as sensitive to IP change it will not vent until higher pressure (a non-balanced octopus is sometimes recommended for this reason, but not essential).

The extra complexity of the balanced second basically amount to one extra O-ring, which IMO is insignificant as compared to the complexity of most modern regulators.

A pneumatically balanced second is still a demand valve and will only supply air on demand as the diver inhales.

Some pneumatically assisted pilot valve second stage regulators were so sensitive that sometimes felt like they were feeding you air as soon as you started to inhale. I don’t have much experience with most of those regulators, but I believe the old Oceanic Omega could have been one of those.

I personally like pneumatically balanced second stages. I think their over all WOB can be set lower and the adjustment stays more constant since there is less indentation on the soft seat (due to the lighter mechanical coil spring needed). But, it is a personal preference.


If you must have a self closing first stage inlet, I believe the Aqua Lung Legend offers the same feature. Personally, I think they offer a false sense of security and may tend to make some people a bit more careless.

If you don’t use a water tight dust cap, any contaminants that reach the tank interface opening may not enter the regulator right away with the self closing feature, but they will be pushed into the regulator by the tank air pressure the next time you attach it to a tank. It does give a chance to carefully clean the interface, but you would have to be more careful than just using a dust cap in the first place.

I have also inspected those devices (both Oceanic and Aqua Lung) and I am not sure how effective they will be about keeping water out…time will tell.

Oceanic seems to be an very good company, but obviously they haven’t been around as long as Aqua Lung or Scubapro. I would just make sure you have some good local dealers.

 

[mempilot]

If you must have a self closing first stage inlet, I believe the Aqua Lung Legend offers the same feature. Personally, I think they offer a false sense of security and may tend to make some people a bit more careless.

Luis, please explain this.

 

[Luis H]

Originally Posted by Luis H
If you must have a self closing first stage inlet, I believe the Aqua Lung Legend offers the same feature. Personally, I think they offer a false sense of security and may tend to make some people a bit more careless.

Luis, please explain this.

I will try.

First, I am referring to the device in the air inlet that is intended to close when the regulator is not attached to a tank to prevent water from entering the regulator.

Second let me say that as an engineer I am fairly comfortable predicting and analyzing mechanical devices and machinery. I am not so good at predicting human nature, but my observation (partially from a human factors engineering perspective) is that sometimes for some people the knowledge of a safety device may make them a bit less careful if they feel their is low risk (I am not talking in high risk situations). IMHO, some divers already feel that water into the first stage is not a high risk…or they would be far more careful about closing it with a good water proof dust cap.

Again this is just my observation.
I hope this makes sense.

 

[keyshunter]

Thanks for your reply, but I don't think so. Apeks is Apeks. Aqualung are just the (US) distributor, just like they are for Suunto. (I think !!!!!!). Feel free to correct me.

Ok, I'm feeling free. Both Aqua Lung and Apeks are under the corporate umbrella of Air Liquide, a French company. They also own several other diving related companies. Incidentally, annual sales of the entire US scuba industry amount to chump change when compared with the annual sales of Air Liquide.