MODERN-DAY PRODUCT DESIGNERS often perfect their prototypes and only then look for a manufacturer to put them into production.
The economy of the world being what it is, it’s inevitable that a lot of stuff gets put together in China. The risk is that the canny Chinese manufacturer so enlisted then knocks out a load of identical products and dumps them onto the market at a cheaper price, so putting the original developer out of business.
Strangely enough, Italy has always had a good manufacturing tradition when it comes to precision brasswork, and a lot of regulators that bear International brands such as Scubapro, Seac and Mares start their lives as brass rod delivered to the milling and drilling machines in Italian factories. It seems that the Chinese have yet to grab this manufacturing opportunity with any success.
I’m told by the British importer that every product made by the Italian diving equipment manufacturer Dive System is made in its own factories in Italy.
You may not have heard of the brand name before (I hadn’t) but that would probably be because this small company was concentrating on breaking into its strong home market before looking for other countries in which to sell its products.

First Stage
The Italians don’t have much home experience of diving in very cold fresh water, unless you count the Italian-speaking part of Switzerland, but I noticed that the CLV first stage adopted a similar solution to that of the most recent Swedish-made regulators.
The surrounding water is encouraged to swill around the exposed first-stage spring.
This transfers by conduction any small amount of heat in the water to the much colder air passing through the mechanism, which is subject to the enormous fall in temperature that comes with a great drop in pressure.
Otherwise, the first stage is a diaphragm-type mechanism finished in black anodising, with four medium-pressure and two high-pressure ports arranged around its barrel.
As the ports are so close to each other I did have a little difficulty fitting the transmitter for my Suunto computer, and resorted to using it at the end of a flexible high-pressure hose (probably a better solution anyway).
A similarly flexible braided hose supplies the second stage past a rather massive in-line heat exchanger.

Second Stage
The X-Tec second stage is a fairly conventional-looking affair, in a dinky size that anyone would find comfortable in the mouth. The exhaust-T is tiny, but I’ve given up complaining about exhaled bubbles obscuring my view. Every manufacturer seems to be taking this route, but the exhaust port itself looks huge compared to the exhaust-T.
The front of the second stage unscrews readily to reveal a transparent pressure-sensing membrane with a hard inset disc onto which the demand lever bears. Water flows in through the front vents.
The purge valve button is small and easily located by feel, but needs quite a strong push to produce any effect. This had more to do with the way in which the button is mounted in the front plate of the second stage than with the pressure required to pull open the demand valve and allow the gas to flow.
The venturi disruption control used to avoid free-flows in those initial moments of immersion has a long throw, and instead of disrupting the internal air-flow by means of a movable flap, as used in a lot of regulators, this one employs a sleeve that rotates around the demand-valve mechanism to diffuse the flow of gas.
You can’t sell a regulator in some territories unless it has a breathing resistance adjustment. This takes the form of a knob at the side that is screwed down to increase the tension on the valve spring and thereby boost the “cracking” pressure needed to open the valve.

Comfort
If you want to know about regulator comfort, ask Don Shirley. He was Dave Shaw’s support diver, and when his rebreather malfunctioned in a South African cave at 250m, he had to
resort to open-circuit to see him safely to the surface, with a long decompression time.
His own support divers brought him suitable OC supplies of gas during the many hours that he spent under water but I understand that he began to get quite picky about some of the regulators he was being given.
I guess that Italian Michele Geraci was equally choosy when he selected X-Tec regulators to breathe from when he made an open-circuit
sea dive to beyond 212m recently, so I wasn’t expecting to suffer any jaw fatigue in the less-than-50m depths that I’d be reaching, over considerably shorter dive times.. The X-Tec has a silicone mouthpiece.

In The Water
It was unfortunate for Dive System that I was using the regulator with independent twin tanks, and had one of the easiest-breathing regulators on the other side. This meant that the X-Tec seemed a harder breathe by comparison.
I had the BRA set to minimum and the venturi plus/minus set to plus, but it was still harder work. That said, if I hadn’t been able to make the comparison I might not have noticed.
I used the X-Tec with air (the densest gas we are likely to breathe under water) and worked hard to get my pictures of trucks that had fallen from the wreck of the Zenobia to the seabed at around 40m deep.
This mid-price-range regulator gave me all the air I needed and there was no tendency to wetness. Tekkies will love it, although there was no sign of that “gushing” effect beloved of so many of them.
I bet we get to see a lot of these regulators in use in future by those divers in black.

COMPARABLE REGULATORS TO CONSIDER:
Hollis Tech 212 DC-1, £344
Oceanic Delta 4 FDX10, £375
Sherwood SR1, £399
Scubapro MK17 G250V, £339


SPECS
PRICE £360
CLV FIRST STAGE Balanced diaphragm-type
PORTS 4mp 2hp
X-TEC SECOND STAGE Pneumatically balanced
ADJUSTMENTS BRA and venturi plus/minus
DRY WEIGHT 970g
CONTACT www.manfrog.co.uk
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