Hi Harald, welcome to the Fryette Forum! Both the PS-100 and the PS-2A have a patented reactive load circuit built-in that handles guitar amplifier’s power output from 1 watt up to 200 watts. The Power Stations have their own built-in tube power amplifiers, and that power output is what the connected speaker receives regardless of your guitar amp’s wattage. So yes, you can use your 12-15 watt combo and produce 100 watts of output power with the PS-100. You may determine that you only need the PS-2A since it is still plenty loud if need be but costs less and is only minus a couple of features that you may or may not need, see video below. Cheers! Gil
