Highly compliant miniature transducer
Various implementations include miniature loudspeaker drivers. In some aspects, an electro-acoustic driver includes: a diaphragm having a surface area configured to radiate acoustic energy; a suspension coupled to the diaphragm, wherein the suspension is non-planar in a resting position; and a support structure coupled to the suspension and having an outer linear dimension in a plane of the support structure of approximately 6.0 millimeters (mm) or less, wherein the surface area of the diaphragm is at least 49% of an overall cross-sectional area of the electro-acoustic driver in the plane of the support structure; and wherein the suspension between an inner side wall of the support structure and the diaphragm has a rounded shape in the resting position.
1. An electro-acoustic driver, comprising:
a diaphragm having a surface area configured to radiate acoustic energy;
a suspension coupled to the diaphragm, wherein the suspension is non-planar in a resting position; and
a support structure coupled to the suspension and having an outer linear dimension in a plane of the support structure of approximately 6.0 millimeters (mm) or less,
wherein the surface area of the diaphragm is at least 49% of an overall cross-sectional area of the electro-acoustic driver in the plane of the support structure; and
wherein the suspension between an inner side wall of the support structure and the diaphragm has a rounded shape in the resting position.
2. The electro-acoustic driver of claim 1 , wherein the suspension has a half-rolled shape in the resting position.
3. The electro-acoustic driver of claim 1 , wherein the suspension is coupled with the inner side wall of the support structure.
4. The electro-acoustic driver of claim 1 , wherein the suspension provides a stiffness of approximately 10 N/m or less, or approximately 8 N/m or less.
5. The electro-acoustic driver of claim 1 , wherein the support structure is circular, and wherein the outer linear dimension comprises a diameter of the support structure as measured in a direction perpendicular to an axis of motion of diaphragm while radiating acoustic energy.
6. The electro-acoustic driver of claim 1 , wherein the suspension provides a stiffness of approximately 35 Newton/meter (N/m) or less, and wherein the stiffness enhances a spectral output of the electro-acoustic driver.
7. The electro-acoustic driver of claim 1 , wherein the suspension comprises an elastomer.
8. The electro-acoustic driver of claim 7 , wherein the elastomer is molded.
9. The electro-acoustic driver of claim 7 , wherein the surface area of the diaphragm has a portion that is not covered by the elastomer.
10. The electro-acoustic driver of claim 1 , wherein the suspension provides a stiffness of approximately 25 Newton/meter (N/m) or less, and wherein the surface area is from approximately 7 square millimeters (mm 2 ) to approximately 40 mm 2 .
11. The electro-acoustic driver of claim 10 , wherein an outer dimension of the suspension is from approximately 2 mm to approximately 10 mm.
12. The electro-acoustic driver of claim 11 , wherein the driver defines an acoustic volume of approximately 45-90 cubic millimeters, and wherein the stiffness of the suspension is maintained at or below approximately 25 N/m while the electro-acoustic driver radiates acoustic energy at up to approximately 130 decibels of sound pressure level (dBSPL) to approximately 145 dBSPL.
13. The electro-acoustic driver of claim 11 , wherein the surface area is less than approximately 40 mm 2 .
14. The electro-acoustic driver of claim 1 , wherein a ratio of the surface area to a stiffness of the suspension is at least approximately 50 dB relative to 1 millimeter cubed per Newton (1 mm 3 /N).
15. The electro-acoustic driver of claim 1 , wherein a ratio of the surface area to the stiffness of the suspension is 360 mm 3 /N or greater.
16. The electro-acoustic driver of claim 1 , wherein the surface area of the diaphragm is non-planar and acts as a piston in radiating acoustic energy, wherein the non-planar diaphragm is dome-shaped.
17. An earphone with in-ear active noise cancelation comprising the electro-acoustic driver of claim 1 .
18. A high-fidelity earphone or a hearing aid comprising the electro-acoustic driver of claim 1 .
19. An in-ear audio device, comprising:
a controller; and
an electro-acoustic driver coupled with the controller, the electro-acoustic driver comprising:
a diaphragm having a surface area configured to radiate acoustic energy;
a suspension coupled to the diaphragm, wherein the suspension is non-planar in a resting position; and
a support structure coupled to the suspension and having an outer linear dimension in a plane of the support structure of approximately 6.0 millimeters (mm) or less,
wherein the surface area of the diaphragm is at least 49% of an overall cross-sectional area of the electro-acoustic driver in the plane of the support structure; and
wherein the suspension between an inner side wall of the support structure and the diaphragm has a rounded shape in the resting position.
20. The in-ear audio device of claim 19 , wherein the suspension has a half-rolled shape in the resting position.