There is no fixed pattern for selecting magnetic liquid. Selection can be made based on the magnetic field strength, gap size, and frequency characteristics of the speaker.
Item | Category | Selection Recommendation |
Speaker Type | Tweeters and high-frequency drivers | Use magnetic liquid with low saturation magnetization (100–200 Gauss) |
Mid-range and full-range drivers | Use magnetic liquid with saturation of 200–300 Gauss | |
Woofers and alarms | Use magnetic liquid with higher saturation magnetization | |
Magnetic Gap Field Strength | >9000 Gauss | Use magnetic liquid with 100 Gauss saturation |
<9000 Gauss | Use magnetic liquid with 200 Gauss saturation | |
Other Factors | High sensitivity speakers | Use magnetic liquid with low viscosity |
Lower sensitivity speakers | Use magnetic liquid with higher viscosity |
To prevent magnetic liquid splashing caused by coil vibration, sufficient saturation magnetization should be ensured:
Saturation Magnetization (Gauss) | Typical Application |
110–220 | Tweeters, earphones, multimedia devices |
220–330 | Mid-range, full-range, compression drivers, alarms |
330–440 | Woofers, subwoofers, alarms |
Long excursion speakers: Use magnetic liquid with higher saturation magnetization
Speakers requiring frequency response adjustment: Choose magnetic liquid with appropriate viscosity
Strong magnetic field environment: Use magnetic liquid with high dispersion stability
High power or long-term use: Choose audio ferrofluid with low evaporation rate
The viscosity of magnetic liquid affects the damping of the voice coil, thereby influencing the frequency response. Therefore, choosing the proper viscosity is very important.
Viscosity Type | Characteristics |
Low Viscosity | Low damping effect, suitable for high-sensitivity systems |
High Viscosity | High damping effect, suitable for systems requiring low-frequency control |
