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Discussion of diving methods and equipment available prior to the development of BCDs beyond the horse collar. This forum is dedicated to the pre-1970 diving.
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Creed
Master Diver
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Joined: Mon Nov 07, 2005 12:10 pm
Location: San Ramon, CA
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Single vs double stage

Tue Jan 24, 2006 3:52 pm

How do the old single stage Mistral's breathe in comparison to the double stage regs?

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kgehring
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Location: Indianapolis
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Tue Jan 24, 2006 4:31 pm

Double stage regs breathe better and usually can be used with 3000 psi
tanks. Single stage regs should only be used with 2400 psi max.
I am sure others will chime in and have better explanations.

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simonbeans
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Joined: Sat Jun 25, 2005 2:00 pm
First Name: Allan
Location: Rochester NY

Tue Jan 24, 2006 8:12 pm

My experience in comparing the two is limited to a single stage mistral and my royals. I have dove my royals to depths of 115 feet with tank pressures of 2600 to 0. They breathe the same throughout the spectrum. I have dove my mistal to 70 feet and tank pressures of 2500 to 300. The difference in breathing resistance was so slight that I didn't notice any. My experience was not very scientific but both regs supplied all the air I demanded in all positions in those dives. My only comparison is that the Mistral is much louder than the royal. The inhalation comes via a venturi tube and you definitely hear a "roar" or a loud air escaping sound. Not anything that is disturbing, but definitely noticable. Other than that, I like both of these regs and have a tough time chosing which one to dive.
Allan

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YankDownUnder
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Location: Melbourne, Australia
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Tue Jan 24, 2006 11:47 pm

My best breathing double hose regulator is a Heinke Mk III. My best breathing Mistral is a Siebe Gorman. My overall best breathing regulator, for volume, is a Porpoise Universal, the first single hose.

All have venturies of one sort or another. Perhaps that is the difference.

Steve

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Nemrod
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First Name: James
Location: Kansas

Wed Jan 25, 2006 4:27 am

I had my Mistral at 110 feet in Catfish Hole I think it was. The Mistral does not have the ability to accept an octapus or inflator since it has no hookah port. It is louder than the RAM or DA due to the venturi. My Mistral breaths like a charm especially once the tank falls below 2,000 psi. My Mistral breaths better than any of the DAs I have or had or at least equal once the pressure get down a bit. It does not equal my RAMs but I think my Mistral is a good breather and I like the venturi sound, it is a fun regulator to dive. While it is probably best enjoyed a bit shallower I would not hesitate to go to 130 feet with it if needed. But since I have three RAMs with octapus and such why would I--?
James

BROXTON CHUCK

Wed Jan 25, 2006 9:44 am

When I want a lot of noise when diving I use my "mistral" When I want peace and QUIET, I use my BROXTON, or NAVY DA NON APPROVED" :wink:

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