Divesoft Liberty - would appreciate the thoughts of those that dive/have dived one

[Nosmosis]

I have had the Liberty since January. The configuration I went for is the 7L DIR Heavy. To be honest, this is my first rebreather. So far (25 hours so far), I really like the unit, the service, yeah pretty much everything. The DIR heavy is not incorrectly named. It’s ******* heavy as ****. But it is a great tool for boat diving. Love how it trims out, love the feel of two double LP50s on the back as diluent/bail-out. Love the BOV. Enjoy the build even - and the thoughtfulness in design makes things like packing sorb pretty easy.

The weakness - in the heavy, the size and weight make it hard for travel. I however ordered a light conversion kit to help get the unit in a suitcase. The controllers I don’t like as much as Shearwater but they are actually pretty good. So good that when my Perdix died I opted for a Freedom Trimix computer to replace it.

I have nothing but positives on the Liberty really. It’s a great unit so far. i have heard people on the traditional configuration complain that the wing doesn’t have enough lift but for my set up, it works fine.

 

[justinthedeeps]

I have had the Liberty since January. The configuration I went for is the 7L DIR Heavy. To be honest, this is my first rebreather. So far (25 hours so far), I really like the unit, the service, yeah pretty much everything. The DIR heavy is not incorrectly named. It’s ******* heavy as ****. But it is a great tool for boat diving. Love how it trims out, love the feel of two double LP50s on the back as diluent/bail-out. Love the BOV. Enjoy the build even - and the thoughtfulness in design makes things like packing sorb pretty easy.

The weakness - in the heavy, the size and weight make it hard for travel. I however ordered a light conversion kit to help get the unit in a suitcase. The controllers I don’t like as much as Shearwater but they are actually pretty good. So good that when my Perdix died I opted for a Freedom Trimix computer to replace it.

I have nothing but positives on the Liberty really. It’s a great unit so far. i have heard people on the traditional configuration complain that the wing doesn’t have enough lift but for my set up, it works fine.

Great quick description of what the 'heavy' config it is good for, and what it is not On a boat you don't have to juggle one more cylinder of bailout. It's just right there on your back. Surely one reason the boat-based teams love it.

Not so good if you have much of a walk or a challenging entry/exit. More options when you can handle the bailouts separately. I don't recommend the 'heavy' configs to anyone unless they are a powerlifter and/or 95% boat diving, with a hydraulic lift. Also much easier to be flexible on diluent mixes when it's just one quickly removable 3L cylinder. The designers of the stock configs know something. Imagine that!

Congratulations to those thinking about how a BOV can make sense. At least think about it. It is an obvious evolution from the necklace reg, but better. Main arguments against it are simply 'we dont use one,' 'it leaks,' 'you wont develop DSV skills,' or 'I prefer to hold my breath while free-flowing my necklace reg as the only option '

 

[justinthedeeps]

I have seen people fussing around with their Liberty to make it accept pos/neg pressure checks etc, on its own custom handsets. No thank you to that. Sounds like a Poseidon. Slightly over-engineered? But top level divers are doing amazing things on Liberties.

@RedSeaDiver2 have you breathed from the different counterlung configurations? We find zero issues breathing from properly designed back-mounted counterlungs. I know people who got rid of their front mounted counterlungs because they just got in the way, and good BMCLs breathe the same anyway.

rEvo is such a cool swiss army knife, lot of extra features that don't get in your way, but it can be a lot to take in for a new rebreather diver. To me it has that slightly over-engineered 'techno-brick' feel to it.. yet some of the components now look a little dated. The design, approach, durability etc is proven in good hands.

JJ is one of the simplest ways to go for a fully featured rig, and I think there are some good regional instructors for Middle East & Asia. You can put a carbon backplate on the JJ for tropical diving. To flush and dry the lungs quickly without taking everything apart, you can hang the whole empty can/harness upside down from a hook, or clipped to a pulley block etc.

Fathom, XCCR, SF2, ..?

Definitely plenty of sidewinder and chestmount stuff going on. Try before you buy? Lot of instructors out there now pushing new designs that haven't been around very long.

 

[RedSeaDiver2]

I have had the Liberty since January. The configuration I went for is the 7L DIR Heavy. To be honest, this is my first rebreather. So far (25 hours so far), I really like the unit, the service, yeah pretty much everything. The DIR heavy is not incorrectly named. It’s ******* heavy as ****. But it is a great tool for boat diving. Love how it trims out, love the feel of two double LP50s on the back as diluent/bail-out. Love the BOV. Enjoy the build even - and the thoughtfulness in design makes things like packing sorb pretty easy.

The weakness - in the heavy, the size and weight make it hard for travel. I however ordered a light conversion kit to help get the unit in a suitcase. The controllers I don’t like as much as Shearwater but they are actually pretty good. So good that when my Perdix died I opted for a Freedom Trimix computer to replace it.

I have nothing but positives on the Liberty really. It’s a great unit so far. i have heard people on the traditional configuration complain that the wing doesn’t have enough lift but for my set up, it works fine.

Some great thoughts there. I probably won't dive it in full DIR configuration - I'm not a GUE convert and so prefer the more traditional way of rebreather configuration but a lot of what you have written gives me confidence in the Liberty - I just have to wait for the upgraded head that will take the solid state cells! I would have preferred Shearwater controllers, but from what you have said it seems like I can live with the Divesoft ones.

It would be interesting to find out the weight difference for travel between the heavy and the light - without cylinders etc.

 

[RedSeaDiver2]

Great quick description of what the 'heavy' config it is good for, and what it is not On a boat you don't have to juggle one more cylinder of bailout. It's just right there on your back. Surely one reason the boat-based teams love it.

Not so good if you have much of a walk or a challenging entry/exit. More options when you can handle the bailouts separately. I don't recommend the 'heavy' configs to anyone unless they are a powerlifter and/or 95% boat diving, with a hydraulic lift. Also much easier to be flexible on diluent mixes when it's just one quickly removable 3L cylinder. The designers of the stock configs know something. Imagine that!

Congratulations to those thinking about how a BOV can make sense. At least think about it. It is an obvious evolution from the necklace reg, but better. Main arguments against it are simply 'we dont use one,' 'it leaks,' 'you wont develop DSV skills,' or 'I prefer to hold my breath while free-flowing my necklace reg as the only option '

The full DIR heavy rig would be too heavy for me to contemplate, even though I am currently designing my own dive charter boat with lift! To me the full DIR rebreather configuration seems to me to be something that was created by a group that wanted to convince the world that they were the Mensa of the diving world - to me it is just too damn heavy for most people's spines etc.

The other argument about BOV's I've heard is that the BOV is fed off the diluent cylinder and so will be the wrong gas if they have to use the BOV on a hypoxic trimix dive where they are using offboard dil for their bottom gas.

 

[RedSeaDiver2]

I have seen people fussing around with their Liberty to make it accept pos/neg pressure checks etc, on its own custom handsets. No thank you to that. Sounds like a Poseidon. Slightly over-engineered? But top level divers are doing amazing things on Liberties.

@RedSeaDiver2 have you breathed from the different counterlung configurations? We find zero issues breathing from properly designed back-mounted counterlungs. I know people who got rid of their front mounted counterlungs because they just got in the way, and good BMCLs breathe the same anyway.

rEvo is such a cool swiss army knife, lot of extra features that don't get in your way, but it can be a lot to take in for a new rebreather diver. To me it has that slightly over-engineered 'techno-brick' feel to it.. yet some of the components now look a little dated. The design, approach, durability etc is proven in good hands.

JJ is one of the simplest ways to go for a fully featured rig, and I think there are some good regional instructors for Middle East & Asia. You can put a carbon backplate on the JJ for tropical diving. To flush and dry the lungs quickly without taking everything apart, you can hang the whole empty can/harness upside down from a hook, or clipped to a pulley block etc.

Fathom, XCCR, SF2, ..?

Definitely plenty of sidewinder and chestmount stuff going on. Try before you buy? Lot of instructors out there now pushing new designs that haven't been around very long.

Having come from a Poseidon - I found that with its positive and negative checks that if it didn't pass there was usually a legitimate reason why that needed to be fixed.

With FMCL vs BMCL - for me its not a WOB thing but rather I just like manual adds, ADV disconnects etc to all be fixed in place on FMCL's so as I don't have to find them - its just a personal preference thing, and I don't find having FMCL's to take up too much space on my chest.

rEvo, JJ etc don't appeal to me because while they are probably good units they don't have FMCL's which is what I prefer.

XCCR's have a known catastrophic failure point - the membrane in the ADV is too fragile, and the ADV is mounted on top of the shoulder which is something that I don't like.

I've no desire to go down the Sidewinder/Fathom or chestmount path - I'm happy to stick with a fairly traditional configuration that I know.

 

[justinthedeeps]

All well researched!

Yeah the checks are there for a reason, but can be done safely without proprietary computer supervision. Watched a guy go through all kinds of effort to convince a Liberty to finally accept a negative.. the dive went fine, eventually.

On a JJ for the negative test I just close the ADV slider, apply vacuum and watch that the visible ADV membrane stays sucked in "Analog sensor"

The JJ is like an around the shoulders counterlungs, with an external dump valve (BC style pull cord type). Quite different from the rEvo, which has them inside the box, internal ADV, and no external dump.

The JJ front-of-shoulder ADV doesn't quick-disconnect, but you can operate it and/or close it easily with the left hand via the stock slider. rarely needed though. It provides a quick reach for the dil flush if you don't feel like finding MAVs. The dil and O2 MAVs are right there by your chest D rings, standard LPI connects.

FMCL might have slightly more neutral to positive static lung loads.

 

[Wibble]

Congratulations to those thinking about how a BOV can make sense. At least think about it. It is an obvious evolution from the necklace reg, but better. Main arguments against it are simply 'we dont use one,' 'it leaks,' 'you wont develop DSV skills,' or 'I prefer to hold my breath while free-flowing my necklace reg as the only option '

Bailout Valves…

Started without a BOV, had a caustic cocktail (my own fault — DSV partially open thus leaking) and bought a BOV. Dived it for a year and found it to be an embuggerance as it interferes with your head movement, is heavier than a DSV, is a compromise so not as good as a decent second stage and adds hassle removing your deep bailout underwater (e.g. to attach to a looped rope to pass up to the boat at deco on the trapeze)

Worst of all I found that I’d stopped doing any form of bailout tests whilst diving and became, let’s say, wary of taking the mouthpiece out and doing bailout drills. Being wary leads to being concerned, being distrustful of bailing out, or ultimatel getting phobic about bailing out which is an essential skill for diving a rebreather.

I moved back to a DSV after 15 months but using a necklaced regulator (with 90 degree elbow on an adjustable rubber necklace). This is much better as:

• you always know where the regulator is;
• Using a quality reliable second stage that breathes well at all depths and can be swapped for another for maintenance or repair
• there’s none of the ballache of pulling the reg out from the bailout, test breathing, then stuffing the hose back in the bungee loops around the stage.
• It is extremely easy to switch from DSV to necklaced bailout, just like switching regs with sidemount. It’s fast to switch both ways.
• Most importantly ones bailout skills don’t atrophy and it becomes normal practice to test bailout breathe in the water.
• A DSV is much lighter than a BOV and nicer when scootering
• That old bogeyman of sharing gas underwater is a non issue as the bailout reg is on a longhose so can be instantly pulled out of the rubber necklace and passed to the ‘victim’ without needing to remove the loop (a-la DIR)

In short, it’s much nicer to dive with the DSV than a BOV and, most importantly, I feel safer.

 

[justinthedeeps]

Bailout Valves…
Dived it for a year and found it to be an embuggerance as it interferes with your head movement, is heavier than a DSV, is a compromise so not as good as a decent second stage and adds hassle removing your deep bailout underwater (e.g. to attach to a looped rope to pass up to the boat at deco on the trapeze)

Which BOV was it? How was the hose routing? I found the supply hose routing itself can be more of a problem than the BOV itself. Wants to pull or restrict the loop if it's not the right length/orientation/direction. Still comes up for me sometimes.

Worst of all I found that I’d stopped doing any form of bailout tests whilst diving and became, let’s say, wary of taking the mouthpiece out and doing bailout drills. Being wary leads to being concerned, being distrustful of bailing out, or ultimate getting phobic about bailing out which is an essential skill for diving a rebreather.

Valid point here. One reason why instructors shy away from it and just teach DSVs only. "Simpler?"

Otherwise, you have to modify the training and practice procedures to include turning the BOV, AND doing the switch drill to another offboard regulator. And perhaps also simulate a BOV that doesn't supply gas (now it's just a DSV)

But wait, actually that is also very simple and easy to teach, train and practice.
Just put it into the drill. Done

• you always know where the regulator is

So the BOV is a regulator, but yeah having a necklace reg also great for this.

• Using a quality reliable second stage that breathes well at all depths and can be swapped for another for maintenance or repair

The Divesoft BOV breathes fine at 90 metres (I tested this myself). Just like any other modern second stage.

You are right on quick replacement. I haven't had this come up yet. Definitely something to think about.

• there’s none of the ballache of pulling the reg out from the bailout, test breathing, then stuffing the hose back in the bungee loops around the stage.

Definite win for necklace regs (and BOVs) here.

• It is extremely easy to switch from DSV to necklaced bailout, just like switching regs with sidemount. It’s fast to switch both ways.

This is true, but still involves swapping mouthpieces--which (I have heard) has been a factor preventing people with CO2 hits from being willing or able to get off their bad loop gas. Chugging so hard on the DSV that not even a necklace reg is gonna work?



We are also more likely to try take some sanity breaths from a BOV -before- becoming fully hypercapnic. No mouthpiece switch for reality checks. This could really matter when things begin to get weird.

Same for the onset of hypoxia. With limited awareness as the lights start to go out, it could be easier to turn a knob for life-saving sanity breaths than to switch mouthpieces. But it depends on instincts and training. Some will already have strong necklace reg instincts, because of prior habits/training.

In extreme cases, buddy can also operate the BOV knob--even if a diver is failing to do it while getting hits from bad gas.

• Most importantly ones bailout skills don’t atrophy and it becomes normal practice to test bailout breathe in the water.

This is personal choice, it is totally possible to continue to practice switching from BOV to another offboard regulator. I've done it on bailout practice with deco. Can be part of initial descent checks/S-drills.

But you are right that it could be (and often is?) skipped in everyday practice.

• A DSV is much lighter than a BOV and nicer when scootering

I have done ~100 hours on DPVs with the BOV yeah it's a little bit more drag I guess, but I don't notice it. I do use a mouthpiece retaining strap.

• That old bogeyman of sharing gas underwater is a non issue as the bailout reg is on a longhose so can be instantly pulled out of the rubber necklace and passed to the ‘victim’ without needing to remove the loop (a-la DIR)

I just have a separate long reg on the bailout for donation, which also backs up the BOV.

 

[Alex Ouroboros]

rEvo, JJ, XCCR, are worth trying, don’t compare anything to a Poseidon rebreather as they are awful, inspo we’re ok 20yrs ago ,, and even then I thought they were gas hungry. After the above mentioned your on exotics, which are really for people that live and breathe CCR’s your wanting nothing to convoluted to dive that’s dependable, easy to have serviced, and has proven itself.
If I did it all again or reigned myself in I’d have one of the first 3 units I mentioned, east to look after, proved themselves and all have dependable electrics in the form of shearwater..
I know guys that have had all of the first 3 past 200m and that’s in cold water not with wetsuits,

Just trying to give sound advice,