REGULATORS

You can buy a regulator for less than £100, or pay almost six times as much. There is clearly room in this category for making sure that you are getting value for your money and, once more, the best way is to start by defining your diving needs.
The lowest-priced regulator on our list, the Aqualung Spiro Calypso XLC at just £94 (revised to 133.95), could serve the diving needs of most divers, particularly if they stay within a depth limit of 30-35m and are not prone to making huge physical effort during their dives. The low price ticket is achieved by keeping things simple and avoiding unnecessary frills.
This simple piston first-stage design has evolved from many previous models and gives a regulator with decent performance, legendary reliability and low maintenance costs.
You will find similar offerings at the low end of most manufacturers' ranges, such as the Scubapro Mk2 R190, the Mares R2 Nikos or the Cressi-Sub XS2 - all below £120. They are not aimed at those looking for the latest in technology or design, but you are likely to come across them in rental stocks at dive centres, where reliability counts.
The middle-of-the-range group includes a higher proportion of diaphragm first stages, generally offering improved hose layout over the lower-priced group, and following the trend towards down-sizing the second stages. There is plenty of choice in this up-to-£250 bracket, including some old favourites such as the Apeks TX40 and the Scubapro Mk14 M50, and some new offers such as the Aqualung Spiro Titan range.
The £250-up bracket is the bells-and-whistles department, though it does not follow that high performance is related to high price. However, the Ultra Light Scubapro Mk20 G500 offers an all-black ceramic finish and for me remains one of the best-performing piston first stages, yours for 386.
Top of the price range is the Mares Ruby Titanium, one of the few regulators still to have a substantially metal second stage giving good coldwater performance at an asking price of £540.
Second stages are growing more and more knobbly appendages, and there seems to be an idea around that this is to do with improving performance. Well, not entirely.
Some manufacturers, such as Mares and Poseidon, like to set up a regulator so that it gives optimum performance when it leaves the factory and therefore has no need for further fine tuning.
Others have identified a need for the user to feel that they have terrific performance available, but want to hold a bit back for emergencies. This results in adjustment knobs that generally detune the regulator so that it is not so easy-breathing as to leap in to free-flow whenever you move quickly through the water.
The adjustments usually found are, first, some form of venturi deflector that influences the flow of air into the mouthpiece tube and, second, a knob at the side of the second-stage housing to increases the spring resistance. The combined effect of these two adjustments can be to make a high-performance regulator a little stiffer to breathe, but perhaps more economical on gas consumption.
From what I have seen few divers adjust their regulators once they have set them up to their satisfaction, so the size of the knobs and ease of use when wearing gloves are seldom important factors.
However, if you are an inveterate knob-twiddler, do test out the controls wearing your usual gloves.
If you need a regulator that can be used with nitrox you will find suitable models at all levels, even at very reasonable prices. Note the distinction in the tables between those that are ready to go with nitrox, and those that can be converted later.
If you are unsure of your future plans, choose one that is at least convertible. Those that are shown as not compatible probably indicate that the manufacturer currently has no plans to make a conversion kit available. While this does not mean that a savvy technician could not accomplish the conversion, it does mean that your regulator will be outside any warranty agreement, and you will carry the total liability in the case of any mishap.
For further guidance check back with our recent (March 1998) or past regulator surveys for performance figures and user appraisals.