Always respectful when and where you play... Yet you have it on full tilt slowly driving by a cop pulling someone over? I normally hit the mute or some radios have auto quiet button where it turns radio down to 20%.
You're already doing a 155 on music? That's pretty impressive already. I agree with hispl. Unless you plan on doubling the power with a 4-5" coil sub. At your level it's trial and error now