NUX Brownie uses a low-pass tone control filter to simulate the Variac effect (lower the voltage going into the amplifier) for rounding of your tone. The range of tone is controlled yet very useful in dialling in the high end response. The power clipping circuit is crafted from modern low noise op-amp and two red LED. It can create symmetrical clipping that distorts both halves of the signal and keep the sound smooth. True bypass circuits with a high quality TPDP mechanical footswitch makes the bypass signal clarity.