Ever wonder... -Whether you are losing sound clarity due to acoustic resonances? -How tone controls should be set for flat response? -Whether your system distorts sound at high volume levels? -If your stereo image is precisely centered? This indispensable tool helps answer these, and many more questions about your audio system's performance. Bring it with you to the store to evaluate new gear! How it works: This CD contains precise, computer-calculated audio signals. Each sample is as mathematically perfect as the CD audio format allows. Left and right signals are identical in amplitude and phase, allowing you to check channel balance and phasing. Precise sinusoids check frequency response over a range of 5 to 20,480 Hz. White noise exercises the full spectrum uniformly. Precise square waves enable measurement of transient and phase response. Pure and mixed sinusoids at maximum amplitude enable distortion and inter-modulation measurements. Signals announced for easy identification. most on dedicated tracks, easily looped. They are also described by CD TEXT, for players that support this capability. Precise measurements require instruments. An inexpensive sound pressure level meter can measure sound levels in your listening space. An inexpensive voltmeter can measure levels at speaker terminals, and other points in the signal chain. For more sophistication, a precision microphone, oscilloscope, or spectrum analyzer (or a PC capable of these functions) is useful. However, most important characteristics (like smooth frequency response and centering) can be estimated by ear. For example, listen to the 20 - 20,480 Hz frequency sweep (1 second per octave, 10 seconds total,) and adjust your graphic equalizer so there are no apparent peaks or drop-outs in volume. This will compensate for frequency characteristics of both your equipment and listening environment. (Don't be too disappointed if your ears fail to respond at the extremes of this range.)