MUSHRA (MUlti Stimulus with Hidden Reference and Anchor, ITU-R BS.1534) is a subjective listening-test methodology built for comparing several versions of the same audio at once — for example, the same clip through different codecs. Listeners rate all versions on a 0-100 scale in a single screen, with two safeguards hidden among them: an unprocessed reference (which should score near 100) and one or more deliberately degraded anchors (low-pass filtered), which calibrate the scale and let you spot unreliable listeners. Presenting everything together makes MUSHRA more sensitive than single-stimulus tests at the high-quality end, where codecs are near transparent and small differences matter, which is why it is the go-to method for serious codec evaluation.
The book · Volume 5 of 7
Audio for Video: A Complete Guide to Sound in Video Products: From Jitter Buffers and Lip Sync to Atmos, Quality Metrics, and Neural Codecs
MUSHRA is the method to use when you must tell apart codecs or settings that all sound good, and a poorly built test hides real differences. This volume explains MUSHRA in depth with MOS, ABX, hidden references and anchors, and objective metrics like ViSQOL, so your codec decisions rest on sound evidence. Written by Nikolay Sapunov, CEO at Fora Soft.
Running MUSHRA listening tests to choose between near-transparent codec settings?
Tell us the codecs or settings you are comparing and we will design and run a MUSHRA test and deliver results with a clear recommendation. 250+ video products shipped since 2005.
