Bass loudspeaker

A bass loudspeaker including:

• a frame;
• a diaphragm suspended from the frame by at least a first suspension element and a second suspension element, wherein the first suspension element is attached to the frame at a first landing surface on the frame and the second suspension element is attached to the frame at a second landing surface on the frame;
• a magnet unit secured to the frame, wherein the magnet unit includes a permanent magnet and at least two flux guiding elements configured to guide magnetic flux across an air gap;
• a voice coil rigidly connected to the diaphragm;
• wherein the loudspeaker is operable to energise the voice coil to cause the voice coil to move relative to the magnet unit along a movement axis, thereby moving the diaphragm along the movement axis to produce sound;
• wherein the voice coil is configured to sit in the air gap, with a centre of mass of the voice coil having a position along the movement axis that is between the first landing surface and the second landing surface, when the diaphragm is at rest;
• and
• wherein a magnetic flux density at an outer perimeter of the voice coil is 50% or less of a magnetic flux density at an inner perimeter of the voice coil.

An assembly comprising a bass loudspeaker and an enclosure, wherein the bass loudspeaker is mounted in the enclosure, wherein the bass loudspeaker includes:

• a frame;
• a diaphragm suspended from the frame by at least a first suspension element and a second suspension element, wherein the first suspension element is attached to the frame at a first landing surface on the frame and the second suspension element is attached to the frame at a second landing surface on the frame;
• a magnet unit secured to the frame, wherein the magnet unit includes a permanent magnet and at least two flux guiding elements configured to guide magnetic flux across an air gap;
• a voice coil rigidly connected to the diaphragm;
• wherein the loudspeaker is operable to energise the voice coil to cause the voice coil to move relative to the magnet unit along a movement axis, thereby moving the diaphragm along the movement axis to produce sound;
• wherein the voice coil is configured to sit in the air gap, with a centre of mass of the voice coil having a position along the movement axis that is between the first landing surface and the second landing surface, when the diaphragm is at rest;
• and
• wherein a magnetic flux density at an outer perimeter of the voice coil is 50% or less of a magnetic flux density at an inner perimeter of the voice coil.

A bass loudspeaker including:

• a frame;
• a diaphragm suspended from the frame by at least a first suspension element and a second suspension element, wherein the first suspension element is attached to the frame at a first landing surface on the frame and the second suspension element is attached to the frame at a second landing surface on the frame;
• a magnet unit secured to the frame, wherein the magnet unit includes a permanent magnet and at least two flux guiding elements configured to guide magnetic flux across an air gap;
• a voice coil rigidly connected to the diaphragm;
• wherein the loudspeaker is operable to energise the voice coil to cause the voice coil to move relative to the magnet unit along a movement axis, thereby moving the diaphragm along the movement axis to produce sound;
• wherein the diaphragm comprises an outer diaphragm body and a central diaphragm body;
• wherein the central diaphragm body includes an annular wall which extends around the voice coil, the annular wall extending along the movement axis between a first end and a second end of the central diaphragm body;
• wherein the outer diaphragm body is connected to the annular wall at a location between the first end and the second end, such that the second end of the annular wall is separated from the location where the outer diaphragm is connected to the annular wall;
• wherein the first suspension element is connected to the outer diaphragm body;
• and
• wherein the second suspension element is connected to the annular wall at or towards the second end of the central diaphragm body.