Is the New Scubapro C350 Second Stage a balanced SS?

[BoltSnap]

Dear SP,

1. Is the New Scubapro C350 Second Stage a balanced SS?
2. Does it correspond to the Subgear's SG50 or the SG30 second stage?
3. How does it compare in performance to the S360 and the S560 second stages?

 

[scubadada]

Dear SP,

1. Is the New Scubapro C350 Second Stage a balanced SS?
2. Does it correspond to the Subgear's SG50 or the SG30 second stage?
3. How does it compare in performance to the S360 and the S560 second stages?

1. No, downstream
2. Looks exactly the same, similar description, who knows?
3. All Scubapro regulators perform well, expect at least as good or better than the 360, perhaps a click below the air balanced 560

Why do you ask, is this at just the right price point for you, or what? Eagerly await response from SP, not holding breath. With a decreasing number of OEM, these comparisons are becoming all the more difficult. Can't wait to see the new line of Aqua Lung dive computers from Pelagic Pressue Sytems compared to those available from Oceanic, Hollis, et. al.

 

[BoltSnap]

1. No, downstream
2. Looks exactly the same, similar description, who knows?
3. All Scubapro regulators perform well, expect at least as good or better than the 360, perhaps a click below the air balanced 560

Why do you ask, is this at just the right price point for you, or what? Eagerly await response from SP, not holding breath. With a decreasing number of OEM, these comparisons are becoming all the more difficult. Can't wait to see the new line of Aqua Lung dive computers from Pelagic Pressue Systems compared to those available from Oceanic, Hollis, et. al.

I am trying to decide what second stage to get with the MK17 first stage for our school's training equipment. The 360 and 560 are both balanced second stages as far as I know. I want a first/second stage combo that will be used not only in our entry level and advanced courses but also for the Deep and wreck diving specialties (recreational).

In regards to the computers, it appears that SP has moved most of the Subgear computers over to SP's product line. I think that the SubGear, now SP, computers are awesome computers at a great price.

 

[DA Aquamaster]

Dear SP,

1. Is the New Scubapro C350 Second Stage a balanced SS?
2. Does it correspond to the Subgear's SG50 or the SG30 second stage?
3. How does it compare in performance to the S360 and the S560 second stages?

Balanced second stages have always been paired with higher end balanced first stages and that's something of a waste. Provided the IP is stable, which it is on a balanced first stage, there is no need to pneumatically balance the second stage. For example, way back in the day when I started diving, the unbalanced Mk 3 first stage was sold with the unbalanced R080 "High Performance" second stage, while the balanced Mk 5 and Mk 10 first stages were sold with both the unbalanced R109 "Adjustable" and the balanced R156 "Balanced Adjustable" second stages which were exactly the same except for the unbalanced versus balanced poppet assemblies installed in them.

With the Mk 3/High Performance you could clearly feel the increase in breathing effort as the tank pressure (and with it the IP of the first stage) fell. However, with an Adjustable and a Balanced Adjustable tuned to a balanced first stage like the Mk 5 or Mk 10, you couldn't feel any difference at all in the breathing effort. The only real advantage the Balanced Adjustable had was longer seat life as it used a lighter spring, and was less likely to damage the seat in storage over time, if you stored it without the little blue key installed. There was arguably some improved flow in the balanced adjustable with it's more streamlined poppet, but the differences were not noticeable.

However, if you put both an Adjustable and a Balanced Adjustable on a Mk 3, you could definitely tell the difference in performance as the IP fell at lower tank pressures with the Balanced Adjustable giving much lower breathing resistance at low tank pressures.

The same basic principles hold true today. On a unbalanced regulator like the Mk 2, a balanced second stage will make a significant difference - yet they are still sold with unbalanced second stages, where you will notice the increase work of breathing at low tank pressures. For a novice diver that's not a bad thing as it will remind the diver to look at their SPG and end the dive before they run out of gas. With a high performance balanced first and second stage, the only warning you get in terms of increased work of breathing is in the last half breath you get from the tank.

However, on a balanced diaphragm first stage like the Mk 11 or Mk 17, you won't notice any difference in performance between otherwise comparable balanced and unbalanced second stages.

The C200 (which is non diver adjustable) and the C300 (which is diver adjustable) second stages were developed as Europeans have a preference for great performing un balanced second stages and that's pretty much exactly what they were designed to be. The C series second stages were designed by an Italian designer with extensive experience in high performance motorcycle carburetors and he did a superb job on the fluid dynamics of those second stages and they flow air very well.

The C350 is a evolutionary revision of the C300. It addresses a potential issue the C300 had with the poppet and guides rubbing a bit in sandy, silty conditions.

It is not a balanced design, but it is a very good performing design and at the moment the Mk 21 C350 and the Mk 17 C350 are arguably the best bangs for the buck offered by Scubapro.

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Subgear is a brand acquired/created by Scubapro as a means to compete with on line grey market dealers at a lower price point that the Scubapro line. The regulators are however the same as the similar looking Scubapro first and second stages. For example, the SG50 is a Mk 17 C350 with some cosmetic changes, while the SG30 is a cosmetically altered Mk 11 C350, and the SG10 is a Mk 2 with a C200 second stage.

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You might also notice the Tusa RS-790 looks a lot like a Scubapro Mk 17 S360, because it is. Scubapro designs it's own regulator and assembles them in it's factory in Italy, but the parts are made by Tabata on very specialized and high tech machines. It would not be cost effective for Scubapro to invest in that technology for the volume of regulators it sells, which is why companies like Tabata make regulators for several companies. In fact, just three companies - Tabata, Aqualung, and Beuchat produce the parts for the bulk of the regulators sold regardless of brand name. It doesn't mean those companies designed them, it just means they make the parts for them under contract.

In the case of Tabata and Scubapro, they've had a long standing relationship where Scubapro will contract with Tabata to produce Scubapro's designs, and in turn, Tabata will market a cosmetically altered design through TUSA, which is the acronym for Tabata USA.

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Scubapro also has an agreement with Halcyon where Halcyon allows Scubapro to sell some of it's technical dive equipment under the Scubapro name an in return Halcyon sells cosmetically altered Scubapro regs under the Halcyon name. The H-75P is a Mk 25, and the H-50D is a Mk 17, and for second stages the Halo is a G250V and the Aura is an R390. Same regs, same parts kits as their Scubapro counterparts.

 

[scubadada]

Scubapro has acquired Seabear and their H3 dive computer. As mentioned earlier and supported by DA Aquamaster, the list of players gets smaller and the list of similar or identical products gets larger.

 

[DA Aquamaster]

In terms of scuba regulators it isn't getting there - it's been that way for about 60 years with four companies making pretty much everything. In the 1950s and 60s Healthways, Voit and US divers single and double hose regulators were all made by Aqualungs's parent company - Air Liquide.

Scubapro's first offerings the in 1965 were made by Beuchat. In fact, you'll find the original Jet Fins with Beuchat logos.

It's hard to say what's happening with dive computers, other than there is as much or more variety to choose from over all now than at anytime in the past.

 

[BoltSnap]

If Beuchat is making regulators for others, why it doesn't have great regulators for itself? Its regulator product line is weak (in addition to its VERY weak BC line).

 

[Luis H]

In terms of scuba regulators it isn't getting there - it's been that way for about 60 years with four companies making pretty much everything. In the 1950s and 60s Healthways, Voit and US divers single and double hose regulators were all made by Aqualungs's parent company - Air Liquide.

Scubapro's first offerings the in 1965 were made by Beuchat. In fact, you'll find the original Jet Fins with Beuchat logos.

It's hard to say what's happening with dive computers, other than there is as much or more variety to choose from over all now than at anytime in the past.

Hi DA AquaMaster, Is good to see you here again.


Actually, Healthways, White Stagg, Dacor and a few others were having their regulator parts and their tank valves made by Sherwood Selpac. Long before Sherwood entered the Scuba industry with their own name, they were making parts for other manufacturers.

I believe Sherwood had the original piston pressure reducing regulator patent and that is were Healthways and others (including Scubapro, which we all know was a spin off from Healthways) got the piston design from.

Looking at the machined parts from some of the 1970's Scubapro items, I tend to think that Sherwood was also making some of their parts, but I could be wrong about that. I know they went to Italy fairly early, for some items. At the beginning of Scubapro, Gustav Della Valle used to do a lot of shopping in Europe for equipment he could import. In the early 60's Scubapro sold a lot of Cressi equipment, etc.

We often forget that Sherwood was one of the largest (if not the largest) manufacturer of pneumatic valves, in the US and possibly one of the largest in the world. Most industrial gas high pressure cylinders in the US have Sherwood valves. From what I have read, I think their manufacturing capacity has shrank tremendously, but I am not certain.

 

[DA Aquamaster]

Tabata makes a more clear cut example as there is "Tabata" the parent company that makes dive equipment, and "TUSA" which is a sideline involved in selling scuba gear. Tabata makes a lot more money making regulators and scuba equipment for other companies than it makes off the comparativel small volume of scuba equipment sales through TUSA.

I suspect Beuchat is the same way - they are primarily in the manufacturing business, not the scuba equipment sales business and their priorities reflect that.

It's also important to understand that while there are 3 or 4 companies that make most regulators, there are a lot more companies designing regulators that are then farmed out to those few companies to actually manufacture.

On the other hand, there are also some very similar looking designs that are made by the same company and then bought by other companies to sell under their own brand name - but they often have slight variations in certain details and in the overall quality and specifications.

If you work on a lot of regs, you'll often encounter the same design with different brand names. That's particularly true with a certain very popular diaphragm first stage design that a number of companies have sold and continue to sell. You'll find however that brand A's version may use a different diaphragm material than brand B, and brand may use a thinner diaphragm made of yet another material. You'll also discover that the tolerances in the regulator will vary, making some brands much easier to work on and adjust than others. You'll see similar variation in second stages and in some cases the tolerances are both very generous and stacked in the wrong direction, making a particular regulator a real dog compared to an identical make and model reg on the bench next to it. That happens because the company that makes those OEM regs will make them to whatever specification the company buying them wants, and a company shooting for a low MSRP will accept looser specifications in exchange for a lower manufacturing cost.

There is one brand in particular that is very popular in some circles as the company will provide service kits and courses for divers to do their own service work. In general that company's first and second stages are normal iterations of some long standing design concepts and they are capable of excellent performance, and they sell for comparatively little money. But there's no free lunch. The downside of that low price point is looser specifications and while many of those regs are great performers you run the risk of getting one that has a combination of tolerances and parts that overwhelms the designs features such as the micro adjust in the second stage and it just won't perform well without swapping out some parts.

That's sometimes an issue on lower end regs sold by high end companies. For example over the years I've encountered a few Scuabpro R195s that breathe very poorly and can't be brought into the required specification for inhalation effort. However with access to a supply of parts, such as levers, springs, and aspirators, it's possible to find a combination of parts that works exceptionally well and turns that dog into a very good breathing second stage. In fact I've never found one that couldn't be made to breathe well, but you've got to recognize that as a lower end model, the specifications have at times been a bit loose and you have to work around that.

In other words, you still pretty much get what you pay for.

---------- Post added November 28th, 2015 at 08:28 PM ----------

Thanks Luis, I knew I was forgetting one of the major players and couldn't put my finger on it, which is ironic as I'm rebuilding valves this afternoon. I'll chalk it up to being 50 and staying up late last night.

As you indicate, Sherwood was in the business of making stuff for other companies long before it sold scuba equipment under it's own banner.

 

[BoltSnap]

In other words, you still pretty much get what you pay for.

DA Aquamaster,

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