Bit Depth ABX Test — 16 vs 8-bit
Can you hear 16-bit vs 8-bit audio? Double-blind ABX trials with binomial scoring prove genuine audible perception. Train your ears. Free in your browser.
Protect your hearing. Start at a low volume. Never raise the volume to make a tone audible. Levels are shown in dBFS, relative to full scale — not SPL.
How it works
Double-blind ABX digital quantization test comparing 16-bit linear PCM with discrete truncation noise levels.
Digital Resolution & Quantization
In Pulse Code Modulation (PCM) digital audio, bit depth dictates the amplitude resolution of the quantization grid:
$$\text{Dynamic Range (dB)} \approx 6.02 \times N$$
- 16-bit: 65,536 amplitude steps (~96 dB dynamic range).
- 12-bit: 4,096 amplitude steps (~72 dB dynamic range).
- 10-bit: 1,024 amplitude steps (~60 dB dynamic range).
- 8-bit: 256 amplitude steps (~48 dB dynamic range; classic 1980s samplers and chiptune sound).
When audio decays toward zero, truncated signals drop into a stair-step waveform, creating harmonic grit. This test allows you to find your auditory threshold for digital resolution.
Frequently asked questions
What is quantization distortion?
When analog amplitudes are mapped to discrete digital steps, rounding errors occur. In the absence of dither, these quantization errors correlate with the audio signal, producing harsh harmonic distortion and gritty decay tails.
Why is 16-bit audio considered the CD standard?
16-bit linear PCM provides a theoretical dynamic range of 96 dB (6.02 dB per bit). With proper triangular probability density function (TPDF) dither, the perceived dynamic range exceeds 115 dB, surpassing the ambient noise floor of typical listening rooms.
Where does quantization noise become noticeable?
At 8 bits (48 dB dynamic range), quantization buzz is easily audible during reverb decays and quiet passages. At 12 bits, it is subtle and requires high monitoring gain to detect.