Quark AA Regular - adding the AA2 tube

I have the Quark AA regular and run it on AA or 14500. On 14500 it is much brighter on Max (with AA max and high are about the same).

Not too long ago I got the Nitecore IFD2 and realised I much prefer the size of a 2AA torch so though I might get the AA2 tube and turn my AA into an AA2.

Looking at the specifications I am amazed at how much extra runtime 4Sevens say the AA2 gets on lower outputs compared to the AA.

Clearly the higher voltage of the AA2 gives a high max output and actually has a lower runtime on max than the AA version, but go lower down the outputs and the increased runtime seems out of proportion.

Comparing the specified runtimes:

AA - High: 85 OTF lumens for 1.5 hours (250ma)
AA2 - High: 83 lumens for 5 hours (250ma)
3.3 times runtime of a single AA

AA - Medium: 22 OTF lumens for 6 hours (50ma)
AA2 - Medium: 19 lumens for 24 hours (50ma)
4 times runtime of a single AA

AA - Low: 4 OTF lumens for 48 hours (10ma)
AA2 - Low: 4 lumens for 120 hours (10ma)
2.5 times runtime of a single AA

AA - Moonlight: 0.2 lumens for 240 hours (1ma)
AA2 - Moonlight: 0.6 lumens for 1277 hours (1ma)
5.1 times runtime of a single AA!

So if you were going to carry 2 AA batteries you would get much more runtime using the AA2 configuration than the AA and swapping the battery once.

Is this simply all down to the AA battery being much more efficient a delivering power at lower currents and having much less internal loss when run this way? However if this was the case, why doesn't it catch up on the lower outputs such as moonlight mode?

Is the AA2 configuration also draining the batteries more and therefore squeezing more energy out of them?

I realise I have quoted runtimes for the S2 edition of the AA2, but the R5 edition is mostly the same except for the moonlight runtime is not as long at 720 hours, but still 3 times the runtime of the AA version

All I can guess is that the driver is more efficient at the higher voltage. Now that I think of it the quark has 2 drivers (boost and buck). I guess the single AA cell uses the less efficient one most of the time and the 2xAA uses the more efficient one most of the time.

tre said:

All I can guess is that the driver is more efficient at the higher voltage.

Click to expand...

Right. In general, buck circuits are more efficient that boost circuits.