What does the term PhaseShift180 actually mean?
Phase shift is any change that occurs in the phase of one quantity, or in the phase difference between two or more quantities.
Phase difference is the difference, expressed in electrical degrees or time, between two waves having the same frequency and referenced to the same point in time.
Two oscillators that have the same frequency and no phase difference are said to be in phase.
Two oscillators that have the same frequency and different phases have a phase difference and the oscillators are said to be out of phase with each other.
The amount by which such oscillators are out of phase with each other can be expressed in degrees from 0° to 360°.
If the phase difference is 180° then the two oscillators are said to be in antiphase.
If two interacting waves meet at a point where they are in antiphase, then destructive interference will occur.
This is the meaning behind the band name PhaseShift180...