Modifier behaviour?

Hello!

To smooth a square waveform for one of the LFO´s, I used the appropriate modifier as:

srce mod1 : dest osc1 : amnt 24
in1 lfo1 : in2 =256 : oper lag

The result sounds like an offset in the modulation range and not the different in pitch as if the same LFO would be set directly as a modulation source.
Is the modifier approach in general unipolar?

Many thanks,
Martin