[Zirondelle76]

Flanger effect? Is that like an echo that should be heard when the long haired guy sings “like an endless flowing river?”?

[asinclair]

The flanger effect is a sliding filtering. Originally referring to the use of reel-to-reel tape recorders with the same recording, one of which is slightly made slower in a canceling effect. See https://www.youtube.com/watch?v=NAqQvs_WXs8 for an example of the effect.