Treble response

Treble response is the high frequency portion of an audio system's frequency response. In an analogue recording, increasing the running speed of the recording medium increases its ability to reproduce high frequencies. Thus a reel to reel audio tape running at 15 inches/38 cm per second will generally have better treble response than one running at 7½ ips/19cm/s. In a digital recording, increasing the sampling rate results in a higher bandwidth and thus typically better treble response. Factors that may impair the treble response of an analogue tape include worn or dirty recording and/or playback heads, or heads with incorrect azimuth alignment. Likewise, a 45 rpm record will generally give better treble response than a 33 1/3 rpm disc. It should however be noted that the grooves near the centre of a record move more slowly than those at the edge (since they are moving at the same angular velocity but have a smaller diameter), so that the record's treble response diminishes as the needle moves inward.