Thiele-Small Parameters of a transducer
Thiele-Small parameters (commonly abbreviated T/S parameters, or TSP) are a set of parameters to characterize the low frequency behavior of a transducer , as can be measured at small signal levels and used for the design of loudspeaker systems. These parameters are named after A. Neville Thiele and Richard H. Small, who pioneered this line of analysis for transducers.
Out of the fundamental parameters other parameters can be defined. They are called small signal parameters and are more commonly used and easy to measure.
Contents
Fundamental parameters
The fundamental parameters are physical parameters of the transducer that are commonly used in transducer equivalent schematics. Some of these values are neither easy nor convenient to measure in a finished transducer. Out of the fundamental parameters other parameters can be defined. They are called small signal parameters and are more commonly used and easy to measure. So when designing speakers using existing transducers, the more easily measured parameters listed under small signal are more practical.
Fundamental parameters
| Sd | piston area | [m2] |
| Mms | moving mass inclusive air load; mass of voice coil and diaphragm alone is known as Mmd | [kg] |
| Cms | compliance of the suspension | [m/N] |
| Rms | mechanical resistance of the suspension | [kg/m] |
| BL | force factor | [N/A] |
| Re | DC resistance of the voice coil | [Ohm] |
| Le | inductance of the voice coil | [H] |
Small signal parameters
These parameters are calculated out of the fundamental parameters. The small signal parameters can be determined measuring the transducer impedance around the resonance frequency of the transducer.
Large signal parameters
Other parameters
