Hi B16JOP, Chrissie asked me to pop over and help you out
firstly dual coil cartos will work fine on the Lavatube ...in fact it will happily work with anything you put on it with a 510 connection
the confusion comes as the Lavatube has a built in amp limit set a 2.5amps that saves pushing too much power to the atomiser/carto and burning it out
what this means in the real world is if you put say a 1.5ohm dual coil carto on the lavatube then you can up the voltage if you wish but the lavatube will limit it at 3.8 volts (as 3.8volts/1.5ohms = 2.5amps)...the lavatube will still show the voltage that you set it at but the output will remain limited to 3.8 volts ...hope that makes
sense
here is a table with a few sample calculations
1.5 ohm between 3.0v - 3.8v
1.7 ohm between 3.0v - 4.2v
1.8 ohm between 3.0v - 4.5v
2.0 ohm between 3.0v - 5.0v
2.5 ohm between 3.0v - 6.0v
2.7 ohm between 3.0v - 6.0v
3.0 ohm between 3.0v - 6.0v
as you can see to get the best out of the Lavatube and use the full voltage range its best to use a 2.5ohm atomiser/carto etc