How Does Timecode Vinyl Work? (Pt. 3)

Summary

How Does Timecode Vinyl Actually Work? (Pt. 3) Wed 27 August 2025 Jan Claußen traktor, timecode, dvs, vinyl control Since its release in 2011, the Traktor Control Vinyl MK2 has sparked curiosity among digital DJs and audio developers alike. Its timecode format stands apart from Serato’s, which we explored in the previous posts. With the MK2 system, Native Instruments introduced a more advanced timecode that boosts resolution and accuracy by applying advanced cryptographic techniques. In this post, we’ll break down how it works at a basic level and how Mixxx is processing the signal. Recap: How Serato Timecode Works Serato’s timecode is built around a Linear Feedback Shift Register, modulated onto a 1 kHz carrier using amplitude modulation (AM) - a legacy technique from radio transmission. The demodulation process is relatively simple: when one stereo channel crosses the x-axis, the other hits a peak. If that peak exceeds a certain threshold, the system reads it as a 1, if not, it’s a 0. We covered this in more detail in DVS Internals Pt. 1 and Pt. 2. The Traktor MK2 Signal Below is a signal that resembles what you’ll find on the Traktor MK2 Control vinyl/CD, which has been specifically generated for this blog post by using a Raised-Cosine Filter to modulate a random sequence onto the carrier. The carrier wave operates at 2500 Hz, a significant increase from Serato’s 1000 Hz. Advantage: The higher carrier frequency allows for 2.5× greater resolution. Upon inspection, this waveform clearly doesn’t use amplitude modulation - the amplitude remains constant. Instead, it appears to be offset-modulated, where the signal is shifted vertically from the x-axis. This is a non-standard technique not commonly used in typical modulation schemes. On the original vinyl version (not shown here due to copyright), the offset can be so large that the signal floats entirely above the x-axis for multiple cycles - making zero-crossing detection impossible. Even when that doesn’t happen, t...