• Welcome to ScubaBoard


  1. Welcome to ScubaBoard, the world's largest scuba diving community. Registration is not required to read the forums, but we encourage you to join. Joining has its benefits and enables you to participate in the discussions.

    Benefits of registering include

    • Ability to post and comment on topics and discussions.
    • A Free photo gallery to share your dive photos with the world.
    • You can make this box go away

    Joining is quick and easy. Login or Register now by clicking on the button

interesting comment from dive shop owner

Discussion in 'Diving Into New Gear' started by Michael Jastrzebski, Nov 6, 2019.

  1. АлександрД

    АлександрД Manta Ray

    # of Dives: 100 - 199
    Location: Moscow, Russia
    772
    1,120
    93
    Michael, I`d try to explain why old regs is better than new Is there really a difference?

    It is not a problem of big membrane, it is a problem of hoses:
    Membrane of doublehose is plased not on the same level, as mouthpiece. And breathing difficulties has sources from column of water, between membrane and your mouth.
    single_vs_double_hose.jpg
     
    AfterDark and chillyinCanada like this.
  2. Hickdive

    Hickdive Solo Diver

    # of Dives: 1,000 - 2,499
    Location: Glasgow, UK
    1,017
    638
    113
    Provided you can parts for them there is no reason why an older regulator can't be used.

    However, don't imagine that the older regulator will perform as well as a more modern one. The reason is that older designs from the eighties and earlier were never subject to work of breathing (WOB) tests. Only once the ANSTI test machine was invented could direct regulator v regulator comparisons be made. Some manufacturers and regulators didn't do particularly well in independent WOB tests on the ANSTI and I'm afraid US Divers models, part of the Aqualung group, was one of those poorer performers. In fact, when the EU introduced a minimum standard for regulators (EN250), US Divers disappeared from the European market.
     
  3. runsongas

    runsongas Great White

    # of Dives: 500 - 999
    Location: California - Bay Area
    3,356
    1,260
    113
    en250 only came out in 2000. that was also around when aqualung renamed their reg lines and got rid of La Spirotechnique and US Divers to rename everything under the Aqualung brand. The Titan and the Conshelf are virtually the same regulator, using the same service kit, and a large number of the same parts. The titan is en250 rated. The discontinuation of US Divers had more to do with rebranding than en250 requirements.
     
  4. GJC

    GJC Solo Diver

    # of Dives: 100 - 199
    Location: Southern California, USA
    318
    217
    43
    Excellent point and one of the factors I failed to remember that affect ease of breathing.

    Back to the OPs question:

    -The size of the diaphragm is only one factor that could determine breathing effort. A larger diaphragm (on a Royal Aquamaster vs Conshelf XIV) does not make breathing easier in my experience when the regulators are serviced and adjusted correctly. Other factors (mentioned above) have a greater effect on effort of breathing.
     
    АлександрД likes this.
  5. BRT

    BRT Giant Squid

    10,725
    6,669
    113
    It will take less vacuum to move the larger diaphragm but will require more volume to produce that vacuum.
     
  6. GJC

    GJC Solo Diver

    # of Dives: 100 - 199
    Location: Southern California, USA
    318
    217
    43
    This is true. But when a dive regulator is designed, the amount of vacuum to move the diaphragm is also affected by the length of the lever on the diaphragm and the strength of the spring on the lever. You can't just say if it has a bigger diaphragm, it must be easier to move it. You need to consider all the other components. A regulator with a larger diaphragm and a short lever and stiff spring can make it very hard to breath from.
     
  7. AfterDark

    AfterDark Solo Diver

    # of Dives: 1,000 - 2,499
    Location: Rhode Island, USA
    7,971
    3,455
    113
    yeah but that ain't what he's got.

    The op's reg is a time proven designed winner, because of that it benefits from the larger diagram.
    Same for your post @BRT volume isn't an issue with the OP's reg. The question was about the OP's reg, not a general statement.
     
  8. AfterDark

    AfterDark Solo Diver

    # of Dives: 1,000 - 2,499
    Location: Rhode Island, USA
    7,971
    3,455
    113
    Good post same thought came to me when I read that post. That's what a crouth strap is for, to kept the tank and therefore the reg can in the right spot.
     
    АлександрД likes this.
  9. Michael Jastrzebski

    Michael Jastrzebski Angel Fish

    # of Dives: 200 - 499
    Location: Oakland, CA
    7
    6
    3
    This is super interesting and insightful however the disappearance of the US Diver brand occurred per my understanding from purely marketing/business reasons when french La Spirotechnique changed its name to Aqua Lung in 2003. If there is any concrete data that would suggest the regulators weren’t meeting the new standards I would like to see that. (Sorry, I just realized someone before me wrote essentially the same thing)
     
    AfterDark likes this.
  10. Hickdive

    Hickdive Solo Diver

    # of Dives: 1,000 - 2,499
    Location: Glasgow, UK
    1,017
    638
    113
    Diver magazine ran many popular regulators through an ANSTI machine. US Divers and certain Aqualung models failed to meet EN250,
     

Share This Page