05/14/2025

Diving regulators: Tecline, Beuchat, Seac – How to make the right choice?

The history of the regulator

From the dream of exploration to controlled depths

Since ancient times, man has dreamed of breathing underwater. But it took until the 20th century for a device to make this really possible, safe and effective: the diving regulator.

Before the modern regulator: the first ideas

As early as the 17th century, systems for breathing under water were imagined, but they remained rudimentary: diving bells, air hoses, or tanks carried on the back.

In the 19th century, engineers like Rouquayrol and Denaysubsidies developed a compressed air regulator for divers. This system, still far from the autonomous regulator, inspires future inventions.

Birth of the modern regulator

History regulator

Scaphandre Museum – Espalion:

The story changes radically thanks to two French people, cock-a-doodle!

Jacques-Yves Cousteau, Navy officer passionate about diving, and Émile Gagnan, engineer at Air Liquide.

Together, they invent the "CG45", the first modern two-stage autonomous regulator.

It allows you to breathe compressed air on demand, depending on the ambient pressure.

It is simple, reliable, and above all: it frees the diver from the surface.
It is the birth of autonomous scuba diving as we know it today.

Years 1950-70: democratization and innovations

The regulator becomes more compact, reliable and comfortable.

Recreational diving is developing worldwide and brands like Aqua Lung (founded with Cousteau) or Scubapro are launching into industrial production.

Since the 1980s: technologies and performance

Appearance of compensated expanders, for stable breathing at all depths, and improvement of materials: titanium, light alloys, anti-icing systems...

Development of regulators adapted to extreme environments: cold waters, great depths, technical diving.

The usefulness of the regulator

Pressure reducer Tecline tangler

The regulator reduces the high pressure of the air contained in the bottle (about 200 to 300 bars) to a breathable pressure, adapted to the diver’s depth.

The first stage is attached to the bottle via a DIN connection (formerly the stirrup) and allows the air pressure to be greatly reduced so that it is breathable (generally between 8 and 11 bars above ambient pressure).

The 2nd floor, which you have in your mouth, adapts this pressure to each breath and allows you to breathe the gaseous mixture that you have in your bottle, thus allowing a comfortable and natural breathing.

Without it, diving would not be possible. It protects the diver’s lungs by avoiding an air intake at too high pressure. In addition, it allows breathing, regardless of the depth (depending on the type of regulator). In fact, it is a vital element for underwater safety and comfort.

The different types of regulators:

There are two types of pressure regulators: piston or membrane.

The first, piston, is easy to use and is recommended for schools or diving centers intended for initiation.
The second, more efficient and more comfortable, will satisfy regular or experienced divers.

Note that there are two types of diaphragm expanders:

Uncompensated diaphragm regulator

Uncompensated diaphragm regulator halcyon

On uncompensated diaphragm regulators, the average pressure (MP) decreases as the pressure in the cylinder falls. This makes the regulator less flexible at the end of the dive, thus reducing respiratory comfort. This phenomenon increases with depth, which limits the use of this type of regulator to a maximum depth of about 20 meters. On the other hand, these models are distinguished by their great robustness and simplicity of maintenance.

Features:

Variable performance: breathing becomes less fluid at the end of the dive.
Sensitivity to depth: the more the depth increases, the more the respiratory effort becomes perceptible.
Simple, robust and economical technology.
Very easy to maintain.
Recommended for: shallow dives (up to 20 meters), recreational use or training centers.

Compensated diaphragm regulator

Compensated diaphragm regulator Beuchat

Compensated diaphragm expanders, whether first or second stage, ensure stable operation regardless of the depth or pressure remaining in the block. This constancy of performance explains a higher purchase and maintenance cost. These regulators are particularly suitable for dives beyond 20 meters. Appreciated for their reliability, performance and ease of maintenance, they are ideal for regular use and for use at any depth.

Features:

Regular and fluid breathing, from the beginning to the end of the dive.
Stable performances, even at great depth or in demanding situations.
More sophisticated technology, with more moving parts.
Maintenance a little more expensive, but often spaced out.
Perfect for: regular, technical divers, or those who go beyond 20 meters.

Selection: Regulator R2 TEC2 - TECLINE and Diaphragm diving regulator VR 400 DIN 300 BEUCHAT

On the side of piston regulators, there are two kinds of piston regulators for the 1st stage:

Single piston regulator

Single piston regulator tecline

The simple piston works according to a very basic mechanism: the medium pressure (MP) is regulated directly based on the high pressure (HP) of the bottle.

No internal compensation, so performance may vary during the dive.
Breathing less fluid at the end of the dive, when the pressure in the block decreases.
Very reliable thanks to its mechanical simplicity.
Easy and inexpensive maintenance.
Ideal for: shallow dives, diving centers, occasional use or tight budget, diving clubs for the pool.

Selection: 1st stage regulator R1 Pro TECLINE

Compensated piston regulator

Compensated piston regulator Halcyon

The regulator automatically compensates for pressure variations in the block. It maintains a constant average pressure, regardless of the residual pressure in the bottle or the depth.

Features:

Stable performance throughout the dive.

Fluid and regular breathing, even at great depth or at the end of a block.
More complex design, with more internal parts.
Maintenance a little more technical and expensive.
Often heavier and bulkier, except titanium models.
Ideal for: regular divers, technical, or diving at more than 20 m.

Selection: HALCYON H-50D membrane first stage regulator

DIN/ STIRRUP Connection

The regulator equipped with a DIN connection is fixed directly on the faucet of the block thanks to a screw thread. Sealing is ensured by an O-ring on the regulator which seals at the level of the tap. In the event of a shock damaging the valve head, it may become difficult or even impossible to remove the seal and install the pressure regulator. The DIN system is lighter and offers better sealing than the bracket system, with less risk of leakage. It can withstand a working pressure of up to 300 bars, provided that a DIN 300 bar compatible regulator is used. However, this system is not always compatible with older diving equipment.

To know: all our regulators for sale on our site Diveavenue.com are in DIN connection. The stirrups are available on request, otherwise on order.

When choosing, here are some important criteria to consider:

Respiratory comfort: a good regulator must offer smooth and effortless breathing. Compensated regulators are generally more efficient at this level, especially in depth.

Lightness: a light 2nd stage limits fatigue in the jaw.

Ease of purging: the purge control must be accessible and responsive, especially in emergency situations.

The type of gas mixture used.

Diving conditions in temperate or cold waters.

The number of high-pressure and medium-pressure outlets and their orientation.

Important: a regulator must be revised every year according to the recommendation of the manufacturer or your maintenance center. It’s a question of safety! Diveavenue offers a regulator maintenance and overhaul service, contact us to learn more.

To inform you about the maintenance of your regulator, it must be overhauled:

According to manufacturer’s recommended intervals.
After six months of intensive use.
As soon as signs of wear or degradation appear.
If breathing becomes difficult.
Or the slightest doubt about its proper functioning or a shock compromising its proper functioning.

When it comes to regulator maintenance, caution is never excessive. For more information, see our complete guide on diving regulator maintenance.

Our selection Diveavenue

Diveavenue is a team of passionate divers with 15 years of experience online, offering you more than 80 brands and over 400 references, accompanied by personalized advice and attentive to its customers, offering you personalized customer service 5 days a week. Today and in this blog, the Diveavenue team enlightens you on choosing your next regulator, among major brands like Beuchat, Tecline, Seac and others.