Signal-to-Noise Ratio (SNR)
Signal-to-noise ratio states how far a reference signal stands above measured noise, in decibels.
A larger ratio means less noise relative to that reference under the same conditions. Reference level, measurement bandwidth and weighting must stay attached to the number.
Signal-to-Noise Ratio (SNR) — Equalizer
Here the ratio describes the noise added by the processing path. A quieter noise floor can be useful during pauses and low-level passages.
Compare the same control settings, signal level and bandwidth. Keep any weighting attached to the figure; changing the reference signal can change the ratio without changing the underlying noise.
Signal-to-Noise Ratio (SNR) — Crossover
Here the ratio describes noise on a specified filtered output. A quieter noise floor can be useful during pauses and low-level passages.
Compare the same output branch, gain and filter settings. Keep any weighting attached to the figure; changing the reference signal can change the ratio without changing the underlying noise.
Signal-to-Noise Ratio (SNR) — Optical Equalizer
For an optical-cartridge equalizer, the ratio applies to its optical-cartridge signal path. Reference input or output level, weighting and measurement bandwidth define the comparison.
Keep this path separate from any MM or MC input in a hybrid component. A ratio with a different reference level cannot establish which optical equalizer has the lower absolute noise.
Signal-to-Noise Ratio (SNR) — Reel-to-Reel
Here the ratio describes tape-path noise relative to a specified recorded or reproduced signal. A quieter noise floor can be useful during pauses and low-level passages.
Compare the same tape speed, formulation, level and noise-reduction setting. Keep any weighting attached to the figure; changing the reference signal can change the ratio without changing the underlying noise.
Signal-to-Noise Ratio (SNR) — Tuner
Here the ratio describes noise in recovered audio relative to the test signal. A quieter noise floor can be useful during pauses and low-level passages.
Compare the same reception band, signal strength and mono/stereo mode. Keep any weighting attached to the figure; changing the reference signal can change the ratio without changing the underlying noise.
Signal-to-Noise Ratio (SNR) — Subwoofer
Here the ratio describes electronic noise relative to a stated signal reference. A quieter noise floor can be useful during pauses and low-level passages.
Compare the same input, gain and electrical or acoustic measurement basis. Keep any weighting attached to the figure; changing the reference signal can change the ratio without changing the underlying noise.
Signal-to-Noise Ratio (SNR) — DAC
For a DAC, the ratio describes noise at the analogue line output relative to full scale or another stated output level. RCA and XLR paths can have different reference voltages.
Compare the same output path, reference level, weighting and bandwidth. A chip rating, headphone-output result or dynamic-range figure is not automatically the line-output signal-to-noise ratio.
Signal-to-Noise Ratio (SNR) — Power Amp
Here the ratio describes output noise relative to a reference amplifier output. A quieter noise floor can be useful during pauses and low-level passages.
Compare the same load, reference power or voltage, gain and bandwidth. Keep any weighting attached to the figure; changing the reference signal can change the ratio without changing the underlying noise.
Signal-to-Noise Ratio (SNR) — Headphone Amp
Here the ratio describes output noise relative to a reference headphone signal. A quieter noise floor can be useful during pauses and low-level passages.
Compare the same load, gain setting and reference output level. Keep any weighting attached to the figure; changing the reference signal can change the ratio without changing the underlying noise.
Signal-to-Noise Ratio (SNR) — MC Head Amp
For a phono head amp, noise must be interpreted against the small cartridge signal and chosen gain. The stated input or output reference and weighting are essential.
Compare equivalent gain, reference level and bandwidth. Equivalent input noise is an absolute input-referred noise measure, not another name for the signal-to-noise ratio.
Signal-to-Noise Ratio (SNR) — Preamp
For a preamplifier, this ratio applies to the analogue line stage. The reference level, gain or volume setting and measurement bandwidth determine its meaning.
Compare the same line-stage conditions and weighting. Ratios for an integrated phono stage, tuner or DAC describe separate paths and should not replace the line-stage result.
Signal-to-Noise Ratio (SNR) — Tape Deck
Here the ratio describes tape-system noise relative to a specified signal level. A quieter noise floor can be useful during pauses and low-level passages.
Compare the same tape type, reference level and noise-reduction setting. Keep any weighting attached to the figure; changing the reference signal can change the ratio without changing the underlying noise.
Signal-to-Noise Ratio (SNR) — Turntable
For a turntable, this field describes mechanical rumble from the rotating system relative to a reference recorded signal. It is not the noise specification of a built-in phono stage or digital output.
Compare the same rumble test and weighting. A negative noise level and a positive attenuation figure can express the same separation using different signs; retain the stated convention when comparing results.