Aqualung Impulse 2nd stage metal tube?

[Fishpie]

Having had one apart very recently I can confirm it is not balanced.
There is no balance chamber.
Internally it looks and functions like a Scubapro 109.

 

[NCadiver]

When you look at the schematic posted by Zung, do you see a design that looks like it is pneumatically balanced? Remember, with the early Delta 2nds, Oceanic used to like to call them balanced and, if pressed, they would fall back on mechanically balanced.

Aqualungs design is very diffrent then Oceanic design but similar to Atomics.
Atomic Aquatics Second Stage Regulator Design

Having had one apart very recently I can confirm it is not balanced.
There is no balance chamber.
Internally it looks and functions like a Scubapro 109.

Fishpie can you post a scematic of the 190 I can't get one until Sunday.

 

[Fishpie]

I don't have any diagrams of the 109.
.....but I do have the XR2 in apart right in front of me.
The poppet doesn't have a hole in it and there is no hollow tube, balance chamber or o rings. There is a thin nylon washer between the adjustment screw and spring.

The AquaLung model that is similar to the Atomic/Zeagle/G250/Apeks is the LX/Legend.
The LX/Legend 2nd stage is an Apeks design.