Previous studies have shown that an inverted‐velocity‐profile coaxial nozzle for use with supersonic cruise aircraft produces less jet noise than an equivalent conical nozzle. Furthermore, decreasing the annulus height (increasing radius ratio with constant flow) results in noise reduction benefits. In the present model‐scale study, the annulus was shaped by an eccentric mounting of the annular nozzle with respect to the conical core nozzle. Acoustic measurements were made in the flyover plane below the narrowest portion of the annulus and at 90° and 180° from this point. The model‐scale spectra are scaled up to engine size (1.07‐m diameter) and the perceived noise levels for the eccentric and concentric inverted‐velocity‐profile coaxial nozzles are compared ovcr a range of operating conditions. The implications of the acoustic benefits derived from the eccentric nozzle to practical applications are discussed.