The stethoscope was created with respect to the real proportions and curves.
Blender Rigging Details
The rig has 5 IK (inverse kinematics) controllers. Left and right ear tips Ik controllers that control their position with limits applied & 3 Tube and chest piece controllers that control The POSITION and ROTATION of the tube rig.
The Tube IK controllers have no limit constraints to allow a wide range of movement and rotation, but rotating the IK to very acute angles may result in unnatural bends in the 3d model.
All the preview renders are made using this rig in just a few minutes.
Each bone in the rig is named logically and the weight paint is adjusted manually for the optimal results.