SCUBA PRO MK 17 260 OR MK 17 620 TI ???

[buddhasummer]

Yes it is a whistling sound...

I am a shallow diver....Dark Water Artifact hunter... 35 FT cut off

Then could well be a lack of lube.

 

[lexvil]

The release of the 420 couldn’t have been at a worse time with the world shutting down at close to the same time. I’m glad I got one, using it on all dives for a while now, D350 as a necklaced back up.

 

[shurite7]

SP is doing all it can to move the D420, I'm thinking thus far it's not been a great success.

The nation's reaction to Covid is the primary reason sales have been down, not the reg itself.

 

[BoltSnap]

I pulled 2 dives yesterday on my 260 MK17 and I can say this without a doubt. It breaths better than my 700.....With that being said I am headed out to my LDS to get my 700 tuned Today......I am running my 700 wide open and 260 was run at about or a little over half wide open and it outperformed the A700... I think something is off with my A700 MK17 setup....making a noise in the first stage on inhale....The other mk 17 does not do that...

The difference shouldn't be really noticeable if any. I suspect that your MK17/A700 is perhaps out of tune or that the two second stages, or first stages, are tuned to different specs not because one inherently breaths much different from the other by design.

 

[calabash digger]

Thanks! Got to send my A700 MK17 in for service....

 

[BoltSnap]

Thanks! Got to send my A700 MK17 in for service....

Please let us know if you still believe that there is difference once they are both tuned properly. I don't believe that there is difference between the two in terms of ease of breathing. The difference may be a difference in the "taste" and the "perception" of the user. I have friends who are have thousands of dives including dives to deeper than 100m and swear by the A700 and believe that it is "better" than the other SP second stages and others that believe and swear by other SP second stages.

 

[calabash digger]

I will .... I will tell you this for long shallow water dives the A700 is going to be my go to. It builds condensation in the second stage on long dives and keep my mouth from being dry. ...Its not like my A700 was performing bad it was just a little harder to breath than the 260.Which led me to take it to the shop to get it tuned...Where I found out my first stage is off on the A700 so its going back for repairs.

 

[mictrik]

I will .... I will tell you this for long shallow water dives the A700 is going to be my go to. It builds condensation in the second stage on long dives and keep my mouth from being dry. ...Its not like my A700 was performing bad it was just a little harder to breath than the 260.Which led me to take it to the shop to get it tuned...Where I found out my first stage is off on the A700 so its going back for repairs.

I realize this post is over a year old but am curious how the A700 performed after the service/tune.? I noticed when tuning the A700 that the inside ridge on its mouthpiece impeded some of the venturi effect. You can test this by removing the mouthpiece and comparing.

 

[calabash digger]

I switched to my 260 after I did a couple of dives with it. Sold the 700 to my dive partner who loves it. To me the 260 performs a tad better , mouth does get dry with it .

 

[rsingler]

I noticed when tuning the A700 that the inside ridge on its mouthpiece impeded some of the venturi effect. You can test this by removing the mouthpiece and comparing.

The decreased size of the hole in the mouthpiece is deliberate. It introduces enough turbulence to impede initiation of freeflow despite the assistance of the Venturi vane. The two components are engineered together.
Using an off-brand mouthpiece with a large hole will make the flow dynamics different, and the reg will be more prone to freeflow.