Raat Ka Surma, Chand Ka Chumma

Flanging is an audio effect of mixing two identical sounds - but one being played with slight delay. This results in a distorted sound with different peaks & troughs - which in turn can be manipulated based on the requirement. One of the first persons to use it was John Lenon. Later, as the sound recording became digital, the engineers created an instrument called Flanger - which when attached to any instrument, will create this effect.

In late 70s, RD got his instrument, from one of his trip abroad, and used it for one of his compositions - attaching it the Guitar. As usual, this was the first use of this technique in India.

Since the composition created a very different sound, it also required someone with different kind of vocal rendition. The verse written by Gulzar were romantic - again creating images out of daily routine, but the movie did not have a romantic hero. In fact the song was picturised on Ram Mohan - a character artist, thus freeing the song from the limitation of singer. The location also was far from being termed romantic

As Gulzar, conversing with RD, said in one of their programmes together on radio, this was a composition for which no normal singer could have sung, and thus came in RD.

The composition, one of the highlights of RD's career as a singer, is largely based only on Guitar & the flanging, while a bit of tabla & flute create the effect of a journey - of a train.