Tikpal Audio

Amplification

Amplification: the quietest watt is the important one

Power-stage linearity, noise floor and thermal behaviour — how Tikpal Amp One is engineered to disappear from the chain.

Published June 20, 2026 · Updated August 30, 2026

1 — The question

Music signals spend almost all of their time at a tiny fraction of rated power. Why do most amplifier designs optimise for full output, and how should a design look if it optimises for the first watt instead?

2 — Why it matters

At 1 W into a 86 dB speaker you already play loudly at listening distance. Everything below that — noise floor, low-level distortion, supply ripple — lives inside the dynamic range of real music. A spectacular full-power THD number can coexist with a mediocre listening experience if the quiet end is neglected.

3 — Our approach

  • True-digital Class-D: volume is applied in the PCM domain, the processed PCM is modulated directly to PWM, and a closed-loop power stage drives the speaker — no analogue potentiometer, no signal-carrying conversion stages. The full architecture is documented in the Software-Defined Amplification project.
  • Isolated supply and layout domains so channels and the control plane cannot modulate each other.
  • Noise-floor spectrum as a headline metric, not a footnote.
  • Thermal behaviour verified on the bench over hours, not on paper.

4 — What we have learned

On an earlier analogue-input prototype, the DSP board’s digital supply was coupling into the input stage until a dedicated local regulation chain was added — a problem found only by the noise-floor sweep, not by any THD test. Measuring the quiet end is what found it, which is why the sweep stays in the routine.

5 — Open questions

  • Closed-loop Class-D output-stage and filter behaviour versus the thermal budget of a fan-less chassis.
  • How much DSP headroom room-calibration filters consume at rated power, and where protection should act first.

6 — Related work