Mk17 vs Mk17 EVO

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I never said there was an advantage. The 25 EVO is different than the 25. The body is different and thread pitches were changed for better cold water performance. Also it stops people from mix matching stuff. If you have an older MK25 awesome! You will have it for years to come. If you want to buy a new MK25, it will be an EVO model and it is even better. If you don't want an EVO thennnnnnn....... don't buy one. It really is that easy everyone. No need to hate on a new product. No one really bashes apple when the new I-phone come out do they? People are excited. When a new reg comes out, that is exciting. If you want something new it is available.

Tech tip for everyone...

For piston regs to function their best in fresh water below 38f, IP should be lowered for even better cold water performance. Dry clean air also important.


SP makes outstanding diaphragm regs. They have had 0 hp seat delaminations in the field. Other companies cannot claim that.

I'm not a diaphragm hater. Id use a MK 11 or 17 any day over a MK25 in truly cold water (below 38 fw).

Notice I am not bashing other brands here, you don't wanna use SP? Cool then. But don't act like a company should make the same thing the same way for 3 decades and have them still be in business.

Once again happy diving everyone!
 
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Thanks for the awesome answer. I decided to go with the EVO because its newer, better hose routing and just "shinier". I'm surprised you said the Mk25 would freeflow, at my LDS I asked them what regs they rent out for ice diving. They told me they use the regular regs (not cold water or sealed) because they dont stay down long. Happy I bought my own :)


You are gonna love it!
 
With the same nomenclature, and the non-backwards compatibility, the writing in on the wall....
 
I'll take that as a compliment. I only care that the original poster had a question about SP gear and that it was resolved.

Well guys... its been fun. Time to go teach a few private scuba lessons. Take it easy.
 
Well, another knowledgeable Beaverdiver, just in better mood......

Selling his 'outstanding' SP Diaphragm 1sts, probably he means the to expect 2 - 12psi (according to SP) IP difference between full and near empty tank which is sometimes even higher.

How would he call a AL Legend with it's max 3psi difference, 'Godlike'?:)
 
I am also doing some research in seal diaphragm 1st stage. Mk17 vs the Evo also have port arrangement difference. Original Mk17 has HP port in kind of between the 2 LP ports (on each side wise), and slightly facing away from the valve (slightly toward your head if you have the rig on). The LP ports are vertically aligned. The EVO's port arrangement is like AL legend. HP on the diaphragm end, facing 90 degrees side way. the 2 LP ports are horizontally aligned. At least from single tank point of view, I will like the EVO port arrangment better. But probably not worth $80 to me

And what do you mean by 2-12 PSI difference? And yes, AL legend balancing is amazingly accurate. Not sure how does it make real world difference, but I like accuracy.
 
SP wrote you have to expect a 2 - 12!psi difference in IP between a full and a near empty tank for the MK11 - MK17.

That's quite exact what I have seen over the years, something between 5 - 10psi usually, sometimes up to 15psi.

For me that's not outstanding, but substandard.

In the real world you probably would not feel a difference if you dive with balanced 2nd even with a 12psi IP difference, but with an unbalanced you might.

I just don't like the idea that SP is getting away with producing what I consider substandard diaphragm 1sts, when Mares, AL and others can develop a diaphragm 1st which balances much better, even if it hardly play a role concerning safety or breathing comfort.

It's a little 'b...sh...ing' the customers like producing now the S620Ti, which is supposed to have smaller exhale resistance, so looking good on the ANSTI Machines, but who ever had to cancel a dive because the exhale resistance was too high?

For me all that technically it goes into a questionable direction in SP, profit orientation seems clearly more important than real substancial technical innovations.

I find that disappointing, but I know I'm not alone......(keeping on diving with SP regs):(
 
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I never said there was an advantage. The 25 EVO is different than the 25. The body is different and thread pitches were changed for better cold water performance. Also it stops people from mix matching stuff. If you have an older MK25 awesome! You will have it for years to come. If you want to buy a new MK25, it will be an EVO model and it is even better. If you don't want an EVO thennnnnnn....... don't buy one. It really is that easy everyone. No need to hate on a new product. No one really bashes apple when the new I-phone come out do they? People are excited. When a new reg comes out, that is exciting. If you want something new it is available.

Tech tip for everyone...

For piston regs to function their best in fresh water below 38f, IP should be lowered for even better cold water performance. Dry clean air also important.

I understand you won't stop drinking the Scubapro EVO Kool-aid but please stop serving it.

I heard Rene spout the same thread pitch crap at a service seminar I attended. No actual explanation of how the new thread pic improves cold water performance - he just used it as the justification for throwing backward compatibility on the scrap heap for the Mk 25.

In fact, you've stated that yourself with the "stops people from mixing and matching stuff" comment. What that translates to for long term Mk 25 users and long term Scubapro customers who have happily upgraded to the latest configuration is that Scubapro is no longer interested in selling them the parts and service to do that, but instead wants to force them to buy a whole new first stage, and of course I'm confident the sales staff will want to sell them a whole new first and second stage set.

It reflects yet another change in Scubapro's marketing strategy, and most of those recent changes have basically sucked. Consider for example, the Mk 11 and Mk 17. They have the same basic first stage body and the difference has been in the sealed versus un-sealed ambient chamber. And of course in the use of a thinner diaphragm in the Mk 17 that increases the working range of the valve and thus the flow rate. It's something that can be retrofitted to the Mk 11, but Scubapro doesn't sell it that way as they want you to upgrade to a 17 to get that little bit of extra performance. In other words, Scubapro forces them selves (and their dealers) to stock two separate kits just so Scubapro can create some artificial performance distance between the two designs for sales and marketing purposes. "Screw the customer" didn't used to be Scubapro's sales model.

----

And by the way thanks for the "tech tip".

I've been diving since 1985, I learned to dive in cold water, I cut my technical teeth on Lake Superior wreck diving, and I've got well over a 1000 dives below 100 ft in water temps of 35 degrees F or less in the Great Lakes, in deep alpine lakes and on ice dives. Dropping the IP on a Mk 25 is just a crutch. It will reduce the flow rate slightly, and slightly improve the odds of not getting a freeze flow, but it does not solve the Mk 25's issues on cold water deep dives. It will still require perfect cold water technique to avoid a freeze flow.

It took over a decade after Scuabpro moved away from the SPEC system to get them to even acknowledge that the TIS system in the Mk 20 and 25 just didn't cut it, that there was a valid need for a fully sealed first stage design in water temps below 40 degrees F. Just ask Dean Garraffa and Doug Toth - reg designers who used to work for Scubapro but left and started Atomic Aquatics, largely over issues like this one, and then look what they did with the Atomic first stage. It's what Scubapro could have and should have had in place of the MK 25 TIS (in all it's "better than last year's TIS" iterations) or the current Mk 25 EVO, which is just another effort to put fresh lipstick on that cold water pig.

Scubapro was more or less forced to market the out of house designed Mk 14 as a stop gap until the Mk 16 could be developed as a means to appease dealers who wanted a diaphragm design on the shelf. Scuabpro has done exceptionally well evolving the Mk 16 into the Mk 17 (and by the way made the Mk 17's much more reliable seat and poppet design retrofittable into the Mk 16). The Mk 17 is IMHO the best diaphragm first stage made for deep, cold water diving (although I would not feel under equipped with Aqualung Legend if Scubapro ever stopped making or supporting the Mk 17).
 
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So tell me guys... what manufacturer builds regs with the intention to never ever make a new one?

SP supports regs for decades after they are changed or discontinued. Who else does that? I have had plenty of aqualung stuff in for repair only a few years old with discontinued parts already an issue.

And aquamaster... why you beating a dead horse. I never said a mk25 evo is better in cold water than a 17 a 11 or any diaphragm reg for that matter. It is better than older 25 versions.

As for ip creep? I am just not seeing this and I test every reg I service at 3000, 1500, and 500 with no creep problems. Only time I have creep problems is when someone before us nicks a piston head or orifice. And we all know.... you never want a "nick in your orifice" haha. Thats gets me every time.

And guys Im a SP platinum dealer by choice. I have sold almost every brand through the years. SP is what we believe in after having too many issues with other brands. Atomic regs in rental fell appart. (Knobs and face plates) Oceanic 2nd bodies cracked and 1st stages would need rebuilds after only 1 season. Cressi bcs tore. Hogs had 2nd stage leaks out of box. Zeagle regs didn't last long as rental gear (needing service often). Ist regs are a joke.

All the meanwhile I have a few classics that are over 15 years old in rental. I have mk 5s and 10s still going strong. 20s 25s 11s and 17s that will go 3 or 4 rental seasons no ip creep or worn out hp seats.

So maybe.... I like SP cause I have had very little issues with them and can sleep at night when we recommend it to customers. We are not trying to screw people over. SP has a price point for everyones budget. That is why the 11 and 17 are different not cause they wanna screw the customer.

Not all dive shops are evil guys. And if you dont like SP thennnn don't use their gear. I'm not gonna fault you for it or think you are gonna die diving just cause you use a different brand. But if you are in my neck of the woods and want anything SP we are the people to see.

Hope you guys all got some diving in this weekend. I spent 4 hours in 50 degree water conducting check outs. Students did awesome for it being their first time to rock 7 mils and all the accessories to dive in chilly water.

Dive hard!
 

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