I don't know too much about that amp. I am not sure if that power rating is peak or RMS, and under what load conditions.
Generally, I find most solid state amps drive the LCD2 well up to moderate levels. If you crank it to say cinema levels and the sound starts to lean out and compress, that is when you need more power. The LCD2s do need a lot of power, in headphone terms, to get them up beyond moderate levels and still retain dynamics and tone.
TECHNICAL DATA PHONE-AMP G100
All measurement RMS unwtd., 20 Hz - 20 kHz, Pre-Gain set to 0 dB, Lo-Cut set to DC
Inputs: 2 x XLR female, balanced, 2 x Cinch, unbalanced
Max. Input Voltage: + 21 dBu, Impedanz 10 kOhms
Input Impedance: 10 kohms
Nom. Input Sensitivity: +6 dBu
Amplifier Gain: +8 dB
Overall Gain with PRE-GAIN: -4 / +2 / +8 / +14 / +20 dB
Frequency Range: 0 Hz ... 50 kHz (- 0,5 dB) … 200 kHz (-3 dB)
Slew Rate: 8 V / usec
Dynamic Range 2x 600 R: > 125 dB / 129 dB (A-wtd)
Dynamic Range 2x 100 R: > 122 dB / 126 dB (A-wtd)
Noise: < -98 dBu / -101 dBu (A-wtd)
THD+N (1kHz / 2x10V / 100R = 1W) < -100 dB / < 0.001 %
THD+N (1kHz / 2x18V / 600R = 0,5W) < -102 dB / < 0.0008 %
Crosstalk: < -110 dB (1 kHz) / -98 dB (15 kHz)
With 2053 mw at 60 ohms
With that setting it starts to get loud around 12 O'Clock gain 8 db (stock setting)
I guess it's enough power then no?