Suunto D4

When I started doing Free Immersion dives shortly before Vertical Blue 2008 I knew I was going to need a deeper gauge to read below 100m. Suunto stepped up to the plate, and altered one of their -the new model that has replaced the D3 as specialised gauge for freediving.

There has already been talk about its sharp design and quality materials, but what impressed me mostwith the D4 was its functionality: accurate, intuitive programming, and attention to details, including:

easy to depress.

- To enter dive mode takes iust a single button press, and to turn dive mode off (so necessary for when you are safetying and need the stopwatch, or spearing/playing in shallow water and don‘t want to clog up the dive log) is just two clicks.

- There is a 'depth notify' as well as an alarm, and both are very audible, so for those who need to mouthfill at exactly 38.5m, you wont miss it again! A surface interval alarm makes it easy to set recovery times for training tables.

- The D4 comes with a clear plastic sticker which can be applied to the screen (like an ipod) to protect from scratches. Big improvement on the D3's chunky plastic guard.

- When viewing the dive profile (which is displayed on the screen as a graph), you can stop or speed up the replay at any point. The water temperature is graphed so that you can see how it changes with depth.

- The display can be backlit with green light: essential for when you are diving in murky water, or when doing naked statics in the pool at Long Island Breezes on the last night of Vertical Blue 2008...

Have you tried the Mares Nemo Apneist by Sebastian on 2008-04-28 11:59:38

Not yet. Any good? by admin on 2008-04-28 12:07:29

Naked statics?! What horrible images I have in my mind now...rnrnI like the easy transition from dive mode. When using my D3 during safety, I always have to wear another watch specifically for using as a timer which can be a bit of a pain, and itis one more thing to add to the checklist. Sounds like it might be worth checking out. How do you find it comapred to the Liquivision?

by Mike Lott on 2008-05-01 00:43:30

How is the depth acuracy, dive recording delay? - What does it display beyond the 100m mark? - Thanks, it's a usefull review laying out some important things other reviewers missed. by Kars on 2008-05-01 02:44:46


The liquivision has more information, and may be more accurate. However Eric has discontinued their production for freediving, and is concentrating on the X1 for tech diving.rnSuunto sent me the sheet of calibrations they did for my particular unit in a pressure chamber, and they were very accurate: not more than 20cm out at depths below 100m. It samples 3 times per second, so very little delay. D4's cannot display depths deeper than 100m (mine was altered for the competition). If you are planning on doing 3 digit dives soon then you might want to look at a D9, otherwise the D4 is best.

by admin on 2008-05-01 07: 14: 14

Thanks for the review. I bought one mainly for its freediving capabilities and for a bit of scuba. I ended up doing a bit more scuba than planned and found it to be more powerful than expected. done a nitrox and air dive on the same day. You stay in nitrox mode for both dives and adjust the percent oxygen. You can adjust the partial pressure of oxygen for calculation of maximum operating depth, and the oxygen limit fraction is given as a percentage. The dive profile is great. Didn't realize that the temperature was also logged till I read the article. The dive planner is easy to use and access. I wish it calculated average depth to assist with calculations of air consumption rates. used the freedivi ng mode a bit and again found it to be easy to use. You can also review the dive profile which is handy and it has depth and time alarms. Make sure you put into freediving mode before you start otherwise the dives get logged as scuba air dives. The strap is sturdy and simple to do up. The watch is sturdy. Make sure you attach the scratch protection on the front lens as instructed in the book. Use warm water when you soak the plastic cover. There is a good demo on youtube on how to do this.

by Derek Bishop on 2011-02-07 15:36:25