Eighteen volts doesn’t mean twice the gain of a 9-volt pickup. What it means is that the pickup will swing twice as much output voltage before its internal preamp starts to clip. That means less distortion in the pickup’s internal pre-amp, but the potential for more distortion in your amplifier’s input stage. If you’re a very dynamic player, most high-output active pickups will distort the pickup’s pre-amp when you play hard. However, a high-headroom pickup like the LiveWires will let you play both loud and soft, without distorting your pickup’s pre-amp. Not having that extra headroom in the pickup acts like a compressor, which is not necessarily a desirable thing, especially if you want more dynamics. In layman’s terms, with 18-volts, you’re eliminating pickup distortion in favor of amplifier distortion; and you’re gaining a wider dynamic range. If you’re an aggressive player, or one who favors dynamics over compression, this is definitely a plus.