The invention relates to a thin type
electrodynamic loudspeaker. The
loudspeaker comprises a speaker frame, and a
magnetic circuit structure, a positioning support
chip and a voice cone which are installed in the speaker frame, wherein the speaker frame is provided with a wiring board. The
loudspeaker is characterized in that the
magnetic circuit structure comprises a U-shaped magnetic conducting yoke, a
magnet, a magnetic pole core and a
voice coil, wherein the U-shaped magnetic conducting yoke is arranged in the speaker frame, and the outer bottom surface of the U-shaped magnetic conducting yoke is tightly combined with the upper bottom surface of the speaker frame; the
magnet and the magnetic pole core are installed in the U-shaped magnetic conducting yoke, the lower surface of the
magnet is tightly combined with the inner surface at the bottom of the U-shaped magnetic conducting yoke, and the upper surface of the magnet is tightly combined with the magnetic pole core; the
voice coil is wound around the magnet and the magnetic pole core, a space is reserved between the inner wall of the
voice coil and the outer wall of the magnetic pole core, and a space is also reserved between the outer wall of the voice coil and the inner wall of the U-shaped magnetic conducting yoke. The invention has the advantages of artful structure, compactness and reasonableness, optimizes the thickness while not decreasing the
magnetic flux and the BL value, and can not produce excessive
heat energy, thereby ensuring the acoustic performance and the reliability of the
loudspeaker.