Scubapro S555 v. R395 second stage

[Splitlip]

Hi All:

I used my daughter's reg (one of my old ones) yesterday, and was surprised at the "effort" required to breath compared to the Mk25/S600 I have been using for the past 5 years.
I decided to buy her a new Scubapro. I am considering the MK11/S555 or the MK11/R395.
I know the S555 is balanced and the R395 is not.
Has anyone had experience with the 2 second stages? Can you tell me how they compare as far as breathing effort goes?
Maybe how the 2 combos compare with the Mk25/S600?

Thanks

 

[halocline]

What does she now have?

I have not tried the S555 so I don't know how it compares to the older G250 and metal cases. AWAP will say that he can barely tell the difference between a SP metal case that's balanced and one that's unbalanced; same case, same first stage, etc., only difference is the poppet and spring.

Theoretically balanced 2nds will have lower WOB due to the fact that once the reg is open, the IP drop in the balance chamber combined with the lighter spring make it easier to keep open. Cracking pressure could be about the same, although typically unbalanced 2nds are set a little stiffer to avoid freeflows with IP changes. In practice, as an example, once I tuned a friend's R190 octo to his 1st stage (he had bought it new and never adjusted it) it performed well enough so that he had to compare back and forth with his balanced 2nd to feel the difference.

I think I've read that the S555 is the same as the S600 without the adjuster.

 

[Splitlip]

Thanks Matt.

She is using a Mares MR12 with Axis 2nd. I think the Axis is unbalanced? The cracking pressure is adjusted as far as itI can without free flow.
I am leaning now more towards the S555.

 

[DA Aquamaster]

The S600 and S555 use the same poppet and are essentially identical except for the adjustment knob. The R395 is unbalanced. An unbalanced reg can be adjusted for low inhalation effort, but the results vary with some breathing very well and others not breathing so well. It ends up being a combination of IP, the strenght of the spring and the lever adjustment so getting max performance can require some parts replacement/swapping.

The S555 would be a sure thing.

 

[Splitlip]

Thanks guys.
S555.

 

[squidster]

Hi All:

I used my daughter's reg (one of my old ones) yesterday, and was surprised at the "effort" required to breath compared to the Mk25/S600 I have been using for the past 5 years.
I decided to buy her a new Scubapro. I am considering the MK11/S555 or the MK11/R395.
I know the S555 is balanced and the R395 is not.
Has anyone had experience with the 2 second stages? Can you tell me how they compare as far as breathing effort goes?
Maybe how the 2 combos compare with the Mk25/S600?

Thanks

I have a MK11/R395, i put an older D300 balanced second on it and there was not much dif
I would go with the R395 second it has been a great performer for me.
if you want a balanced second you may as well get a MK17/S555 or better yet a G250 Vintage.
The problem is its just not that much more money dif if you get the MK11 with the S555 so you may as well get the MK17.
I am not trying to talk you out of the MK11 i just think it make s more since to go withMK11/R395 it s a great set up for alot less $$

 

[Splitlip]

Actually thinking about shifting gears now, LOL.

At this point she may end up with a MK 25. I like the bottom LP port. And I really like the look of the new G250.
A dry chamber is not that important to me right now, which is why I was looking at the 11.

I had been trying to stay away from the inhalation adjustment knob for her. (soak closed, store open). But she will just have to learn to care for her own gear.

 

[Teamcasa]

Look here Scubapro MK 17 / S555 - New $375

 

[oldschool]

You might want to check with your LDS for the MK25 / S555 setup. Scubapro has discontinued matching the S555 with the MK25. Both are still available, just not together. I purchased this setup from my LDS shortly after Thanksgiving. I got a better deal going with the MK25 than going with the MK17. I don't know if any shop still has this combo.

 

[DA Aquamaster]

SP dealers can do some serious discounting on discontinued items and combinations and that can be attractive.

On the other hand, the G250V is the best second stage that Scubapro has made in years and is in my opinon the best new second stage available from any company at the moment.