Noted English engineer/producer Alan Parsons and Cliff Electronics have produced a very useful audio test and demonstration CD that's great for evaluating the performance of audio equipment or any speaker system at home or in a professional studio. Called Sound Check 2, the CD begins with a complete series of 1/3 octave pink noise test signals, pink noise test tones, sweep and warble tones, and sine and square wave spot frequencies all designed to test, align, and troubleshoot audio systems and speakers.

This CD differs from others in two important ways. First of all, two thirds of the total running time (69:45) is devoted to music tracks, sound effects and separate instrument recordings; many especially produced and engineered by Alan himself at Abbey Road Studios, England. Presented in the purest form possible using the finest microphones and instruments, these sound examples use the full dynamic range available to 16-bit/44.1kHz CDs and are without any processing such as equalization or compression.

They are ideal sources for comparing different external processing gear. For many music lovers, used to produced and mixed CDs, these recordings may be the first time they've actually heard musical instruments the way professional recording engineers hear them in the studio at the start of a recording project.

The other main feature is the dramatically improved built-in Audio Response Analyzer sound level meter housed within the double CD case itself. Used in conjunction with the test tones, this AC or battery-powered unit has a LED meter calibrated in ten steps from -15dB to +12dB, a socket for an external microphone for even better accuracy, and complete instructions for set up, operation and the proper way to interpret your results.

The Audio Response Analyzer will help you identify not only speaker and system deficiencies but also room anomalies such as resonances, standing waves and bass build-up problems.