Hafthasht (2019) is a fixed media electroacoustic piece composed for 24 channels. The piece was finished in October 2019 and premiered in Azimuth #8 concert which took place in iii space, The Hague. The core idea of the piece is based on the phenomenon of reverberation or echo. A sound bounces from various surfaces and with each reflection it looses part of its energy until it fades into the silence. This idea is incorporated into the production of the sound materials as well as the spatialization of the piece.

Hafthasht is selected for Giga-Hertz Award 2020, ZKM, Karlsruhe: "Siamak Anvari composed the almost 17-minute composition »Hafthasht« in a 24-channel surround sound version, which allows the nebulous, abstract and yet expressive character of the composition to be experienced immersively. The jury was impressed by the immediacy and freshness of the sounds, as well as by the immediate effect the composition is able to unfold."