That was just what Shin had been expecting her to do. The bass isn't the best at taking a solo from a guitar. It had to do with how people just heard sounds, and the deep tones weren't as easily heard over the higher sounds of the guitar. But that also meant in a live setting like this, the sounds were also more able to physically move through a person. And he's the one with the amp.

He adjusts the pickup volume as he kicks the volume up on the amp itself, just enough to be more noticeable under the sound of the guitar. He moves it slowly as they fight through a crescendo, hiding the physical volume adjustment with the increasing intensity.

When they hit the peak, he drops two octaves, playing closer to the base of the neck and making the entire bridge overhang rumble with his beat. He makes his tune disrupt each phrase she makes, undermining her notes. So the bass giveth, so the bass taketh away.

Of course, he made sure to keep the volume at a level that kept him far from actually drowning out the acoustic guitar. He wouldn't want to give her any good reason to call this off, but he's serious now. His amp isn't set to a soft polite level meant mostly for just him to hear. Her acoustic had announced to everyone that they were playing, but like hell Shin would just give her the spotlight without trying to shake this bridge down.