Aqualung Mistral

[Greg Barlow]

I have made many dives using double hose regs, and have also used the new Mistral. I am not impressed with the new model, as it doesn't follow the original designs in its execution. Plus, I just don't like the looks of it. The hoses are a great improvement over the originals, as is the mouthpiece unit. AquaLung builds a double hose reg called the Mentor that is used for military training and use. At this time it is only sold to government agencies, but with "coaxing" could become available on the civilian market. It is much like the Voit Trieste and Nemrod Snark in that it uses a housing with LP and HP ports.

When I started diving double hose regs were quite commonly used. I have three that have been rebuilt, and I dive with them a number of times each year. While they are fun to use, they cannot physically equal the WOB of a modern high performance single hose model. The fact that the diaphragm is in shallower water (normal swimming position) than the lungs costitutes a greater inhalation effort than what can be achieved with a single hose model. For those of you who doubt the laws of physics try rolling onto your back and see what happens. Or for that matter, get vertical in the water and you can immediately notice the improvement in inhalation effort. This difference in hydrostatic pressure is the reason why most rebreathers use the breathing bags in a chest mounted position.

I love diving and rebuilding vintage double hose regs, along with my several vintage single hose models, but limited my dives to depths of which I could comfortably make a free ascent. When using a bail-out bottle, I have made dives in excess of 100' with the vintage models.

Vintage diving is great fun, and interest in it is growing. Dan Barringer of www.vintagescubasupply.com and Bryan Pennington of www.vintagedoublehose.com are masters at rebuilding the double hose regs.

Greg Barlow
Former Science Editor for Rodale's Scuba Diving Magazine

 

[Alaska_diver]

I recently purchased the Aqualung Mistral regulator and made three dives with it last weekend. It requires more inhalation effort in the horizontal position. It still has the free flow problems at the surface as the old double hose regs did. I used to own and use a US divers dbl hose in the 70's and a Nemrod snark in the early 80's and I dont see much differance in performance where it matters, IE the BREATHING thing. The only positive thing I really like about it (and any twin hose reg) is that the bubbles exhale behind you. And on the new Mistral you can attach all neccessary hoses. It is great for observation and photography if you dont mind "sucking" your air. I am satisfied with mine but I like gadjets too. So no, it is not as comfortable or as easy to breath from as a standard (and less expensive) single hose reg.

 

[MarkUK]

I tested the Mistral for a week on assignment in the BVIs and, to be honest, all it proved to me was the reason all manufacturers went on to single-hose regulators!

The mouthpiece is comfortable, but the breathing is hard in normal horizontal diving position, and then the hose nearly rips out of your mouth when you go vertical or on your back.

Yes, the bubbles do come out behind your head, which allows you to get a little closer to marine life when shooting with a camera, but not a great deal – I can get just as close using my Apeks ATX200 and just holding my breath as I approach for the final shot.

I also didn't like the way the first stage attaches – after spending all that time and money developing the twin hose and exhaust, you'd have thought they could have done something other than just bolt it all on to an existing first stage.

I'll stick with my Apeks and Scubapro regs, I think...

Mark

 

[DA Aquamaster]

I have a few DA Aquamasters and a couple of the the older original Mistrals. I prefer the Mistrals, especially at lower tank pressures.

The new Mistral does not impress me at all. It has the same limitations as the older double hose regs (position of the diaphragm relative to the lungs) resulting in greater work of breathing than with even an inexpensive single hose regulator. And, do to the design, it does not offer the same level of freeze resitance in cold water. Then there is that offensive little hose from the first to second stage. It makes it abundantly clear that it is just a cheap second stage grafted onto a Titan first stage. It lacks the same style and elegence of a "classic" double hose reg.

The price tag is also a killer as you could get a very nice classic double hose reg in fully restored condition for about half the asking price for a new Mistral. And I suspect over time the older double hose reg will hold it's value better.

Like most other double hose reg divers, I would be much more excited about Aqualung marketing a civilian copy of the mentor in order to be able to utilize modern HP and LP ports in a more "normal" manner.

 

[SwimJim]

Like most other double hose reg divers, I would be much more excited about Aqualung marketing a civilian copy of the mentor in order to be able to utilize modern HP and LP ports in a more "normal" manner.

I'll second that. Presently I own four double hose regs, one of which is a DA Aquamaster. I think the DA is a sweet breathing reg and I'd use it more if it had High and Low pressure ports. My Xstreams are better breathers, but the old DA just has a certain intangable coolness factor that I really like. The new Mistral just doesn't make it.

Jim

 

[Luis H]

... resulting in greater work of breathing than with even an inexpensive single hose regulator.

I tend to agree with most of what you write, but I think this is pushing it just a bit.
No question that diaphragm position is a handicap, but (I know that you are very aware) that the handicap can be heavily overcome with tank positioning and swimming attitude.
And work of breathing cycle takes into account the exhalation, which is normally easier from a double hose.

My Poseidon’s or SP D400 may be better breathing, but my well tuned Royal Aqua Master’s doesn’t fall far behind when position properly.

With my new Royal Aqua Master first stage body I should be able to position the regulator so that it is touching my back. As a side benefit, it has built in HP and LP ports (no need for banjo fittings or hookah adapter). I can’t use a dry suit with my vintage Mistral.

Like most other double hose reg divers, I would be much more excited about Aqualung marketing a civilian copy of the mentor in order to be able to utilize modern HP and LP ports in a more "normal" manner.

I'll second that. Presently I own four double hose regs, one of which is a DA Aquamaster. I think the DA is a sweet breathing reg and I'd use it more if it had High and Low pressure ports. My Xstreams are better breathers, but the old DA just has a certain intangable coolness factor that I really like. The new Mistral just doesn't make it.

Jim

I totally agree.

From the diagram that I have seen, the Mentor looks like a great regulator.

 

[Ltstanfo]

Well, my reply is probably too late for everyone that started this thread but here is my "2 cents" worth.

I purchased the new Mistral at my local dive shop last Wednesday (regular model) and have 2 dives on it now. As a point of reference, I have owned a USD DA Aquamaster (long since sold) and still have / use a Royal Aquamaster.

The "pros" -
1. breathes easier then any double hose (including the Royal) I've ever used.
2. You have 1HP and 3 available LP ports for extra items. With a Royal, unless you have one of the extremely rare banjo fittings, you cannot add anything.
3. Uses modern parts (Aqualung Titan 1st stage) so servicing and parts is readily available.

"Cons" -
1. Hoses "float" very bad and need weight to keep the moutpiece from pulling up in your mouth.
2. The "Comfobite" mouth piece is just that... a piece! Tear that thing out and buy something else to use (cure, etc...)
3. Reg will free-flow just like older double hoses so you have to watch attitude in dive and position of reg on surface.
4. Relatively expensive compared to "good" single hose designs.

Summary - if you want to do photography with no bubbles or relive the old days, it's worth it. If you don't even know what Sea Hunt is...don't bother.

Regards,
Ltstanfo

 

[Nemrod]

There is something rare come up from the depths of history, from Old Davy Jones, and only whispered about by brave souls and it's ready to lay down the law. It uses Titan parts (so parts are available), It has LP and HP ports, it breaths better than the new Mistral or just about anything else, the hoses don't float, it is majestic and magnificent. It's name, well, it is none other than the mythical Phoenix Royal Aqua Master. Born of fire from the ashes of history, arisen to reclaim it's crown, hail the King. N

(Note, there are three HP ports, three LP ports and with the hookah port adapter a fourth LP port, no banjo adapters needed.)

 

[divereh]

colt creek diving has one $800, they work really well

 

[Ltstanfo]

Nemrod,

Thanks for the photo. Quite interesting but I've never seen / heard of it before now. Is this an aftermarket rebuild of the Royal? Who does it and what is the process for upgrading an existing Royal?

Thanks,
Ltstanfo