Acoustic Glossary


 

U : Sound and Vibration Definitions, Terms, Units, Measurements ...

UKAS : United Kingdom Accreditation Service is the national accreditation body recognised by government to assess, against internationally agreed standards, ...

Ultrasound Definition.

IEC 801-21-04, acoustic oscillation whose frequency is above the high-frequency limit of audible sound (about 16 kHz)

Uncoupled Mode Definition.

IEC 801-24-18, normal mode oscillating independently of other modes.

See also • Coupled Modes

C

Undamped Natural Frequency

the natural frequency of a structure.
 

Undamped Natural Frequency Definition.

IEC 801-24-09, frequency of free oscillation resulting from only elastic and inertial forces of the system.

See also • Natural Frequency

Under-range the input to the sound level meter is too low for the current measurement range. Change the range.

Under-range % percentage of time an under range occurred

Units • SI Units

Home • Glossary Search • Certified Instrumentation for Hire