The limiter that sees between the samples. Powered by 4× oversampled polyphase FIR detection with a 48-tap Kaiser-windowed sinc interpolation filter, the TruePeak Limiter is the intelligent upstream half of an architecture found nowhere else: Dual-Layer TruePeak Protection. It applies precision inter-sample peak control before your signal reaches the shaping stages — then hands off to the TruePeak Guard downstream, which independently verifies every single sample leaving the output. Two dedicated circuits, one seamless guarantee: zero inter-sample overshoots, period.
Standard limiters measure sample peaks — discrete digital values. But the analog waveform reconstructed by a D/A converter can exceed 0 dBFS by +3 dB or more between those samples. These inter-sample peaks are invisible to ordinary meters and limiters, but they cause real-world distortion in every converter, every lossy codec, and every streaming platform encoder. MixBus Platinum's TruePeak Limiter uses a 48-tap Kaiser-windowed sinc interpolation at 4x oversampling — the same mathematical reconstruction that converters use — to detect and limit these peaks before they leave the plugin.
In FM and HD Radio, inter-sample peaks are the invisible enemy. A signal that reads 0 dBFS on a sample-peak meter can exceed +3 dB between samples after D/A reconstruction — driving transmitter clippers into distortion, triggering composite limiting artifacts, and degrading stereo separation. MixBus uses a 48-tap Kaiser-windowed sinc interpolation at 4× oversampling to detect and control these peaks before they ever reach the output. The result: a cleaner, louder signal that stays compliant through the entire broadcast chain. The same precision applies to streaming — every major platform recommends −1.0 dBTP maximum, and this limiter guarantees it.
Most processors have a single limiter and hope for the best. MixBus Platinum deploys two independent TruePeak circuits that work as a coordinated pair — an architecture we believe is unique in audio processing. The TruePeak Limiter (Stage 10) sits upstream of the shaping stages, applying musical, lookahead-driven gain reduction with full 4× FIR inter-sample detection. It shapes peaks intelligently, preserving transient character while enforcing the ceiling. Downstream, after all shaping, saturation, and clipping have been applied, the TruePeak Guard (Stage 12) independently verifies every sample leaving the output with its own dedicated 4× FIR detector and 0.15 ms instantaneous attack — catching anything the earlier stages introduced.
Enabling TruePeak Limiting automatically activates TruePeak Guard, locking both layers into a seamless protection chain. The result: the Limiter optimizes how your signal sounds, the Guard guarantees how it measures. Upstream precision, downstream certainty — two circuits, zero compromise.
Broadcast regulators and streaming platforms don't care about sample peaks — they measure TruePeak. EBU R128 requires −1.0 dBTP. ITU-R BS.1770-4 defines the measurement standard. Spotify, Apple Music, YouTube, and Amazon Music all enforce similar requirements. Without TruePeak limiting, your audio gets flagged, re-processed, or rejected. With Dual-Layer TruePeak Protection, MixBus guarantees compliance with every major standard — not through a single point of defense, but through two independent verification stages that leave nothing to chance.
Two independent 4× FIR circuits working in tandem — upstream precision, downstream certainty, zero compromise.
