Sample rate is how many times per second an analog-to-digital converter measures the incoming signal, expressed in kHz. The Nyquist theorem sets the ceiling: a 48 kHz rate can represent frequencies up to 24 kHz, just past the limit of human hearing. Video settled on 48 kHz because it divides cleanly against common frame rates and yields a whole number of samples per frame, which keeps audio and video aligned. 44.1 kHz survives from the CD era and still appears in music. Production formats use 96 or 192 kHz for extra headroom during pitch-shifting and time-stretching, then downsample to 48 kHz for delivery.
The book · Volume 4 of 7
Audio for Video: A Complete Guide to Sound in Video Products: From PCM and Codecs to Loudness, Accessibility, and Real-Time Voice Processing
Sample rate choices ripple through the whole product, from capture cards to codecs, and a 44.1 versus 48 kHz mismatch causes drift and pitch errors. This volume covers sample rate in depth with the Nyquist limit, resampling, bit depth and codec requirements, so your chain runs on one consistent rate. Written by Nikolay Sapunov, CEO at Fora Soft.
Mixing 44.1 and 48 kHz sample rates and seeing drift or pitch problems?
Tell us your sources and outputs and we will define one sample rate plan with conversion points, resampler settings and checks. 250+ video products shipped since 2005.
