T

TermLab
Industry-standard SPL meter for competition. Measures 1/3-octave band at specific frequency. Positioned at A-pillar, windows closed. Official meter for dB Drag Racing. → See also: SPL, Competition
Chapter 13.1

THD (Total Harmonic Distortion)
Unwanted frequencies added to signal. Expressed as percentage. Amplifier spec: <0.1% excellent, <1% acceptable. Speaker spec: <3% at rated SPL acceptable. Lower is better. → See also: Clipping
Chapter 1.3

Thiele-Small Parameters
Set of measurements describing driver's electro-mechanical properties: Fs (resonance), Qts (damping), Vas (compliance), Xmax (excursion), Sd (area). Used for enclosure design. → See also: Fs, Qts, Vas
Chapter 10.1

Time Alignment
Delay adjustment compensating for different speaker-to-ear distances. Measured in milliseconds. Calculation: distance difference (inches) / 13,500 = delay (ms). Critical for imaging. → See also: Imaging, DSP
Chapter 12.4