[1] In contrast, a digital signal represents the original time-varying quantity as a sampled sequence of quantized values.
Digital sampling imposes some bandwidth and dynamic range constraints on the representation and adds quantization noise.
[citation needed] An analog signal is subject to electronic noise and distortion introduced by communication channels, recording and signal processing operations, which can progressively degrade the signal-to-noise ratio (SNR).
[2] Once in digital form, the signal can be transmitted, stored, and processed without introducing additional noise or distortion using error detection and correction.
Noise accumulation in analog systems can be minimized by electromagnetic shielding, balanced lines, low-noise amplifiers and high-quality electrical components.