Erica Synths Black Wavetable VCO ROM 3 expands the sound spectrum of the Erica Synths Black Wavetable VCO with eight more great sounding waveforms. After the ROM has been inserted into the free slot on the back of the module (please pay attention to the correct alignment of the chip), it is automatically recognized. The blinking of the first LED indicates that you are selecting the waveforms of the third ROM chip.