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Audio Sample Size
The greater the approximation error, the greater the amount of digital or quantizing noise produced. The solution to reducing digital noise is to use larger sample sizes or bit depth, which therefore correspond to the dynamic range of the system, since it affects the signal-to-noise ratio (for digital systems, this is often measured as SQNR, or signal-to-quantization-noise-ratio). A general rule of thumb is an added 6 dB of dynamic range for every additional bit used per sample.
The CD/DAT standard 16-bit samples, with their impressive 65,536 values for quantizing, provide the theoretical playback system optimum of 96 dB dynamic range.
Digital audio editing programs can often use 20-bit, 24-bit, even 32-bit floating-point or long integer samples to minimize fractional values and the noise introduced when mixing or engaging in other mathematical processes on the samples. Another reason higher bit-depth recording is becoming more attractive as prices come down and storage becomes less of an issue is that quantization errors are much more critical at lower amplitudes, due to the linear amplitude divisions of the quantization process. At very low amplitudes, these errors are much more apparent, acting more like distortion than noise. Higher bit-depth files can be reduced back to 16-bit for things like CD burning, often enhanced by using a process called dither , which tries to minimize the inducement of further digital noise. Dither allows higher bit depths, such as 20- and 24-bit files to be reduced to 16-bits by not doing the obvious, which would be rounding off the extra precision to the nearest 16-bit value. Instead, it combines the least significant bits below the most significant 16 with random values, then rounds up or down to the nearest 16-bit value. If you don't record above 16-bit resolution, try to adjust recording levels to avoid prolonged periods of very low amplitudes while not exceeding the maximum amplitude of the system at peaks ( digital systems do not provide the fuzzy 'headroom' of analog systems--they just run out of values and clip ) . You can see the effect of two different bit depths on the diagram below:
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Music Editing Master is an ideal and efficient audio editing software for home users. It provides powerful and user-friendly editing environment which suits beginners especially
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