A thermal insulating element comprises a first plate forming at least a part of an outer face of the insulating element and a second plate forming a further part of the outer face of the insulating element. The shell body has a bearing seat at the outer side. The active isolator assembly may include a single actuator that is coaxially aligned with a sensor. The multi-position mirror element may also be indexed to direct the beam on a branch path to a fiber optic cable which has a probe at the end of it which may be inserted in a sample fluid or powder to be analyzed, with the reflected light from the probe being directed back on an optical fiber cable to a detector at the spectrometer. The apparatus comprises a manually operable joystick which can be used to operate a compact disc player, and to cause it to play the content on the basis of the viewed image of the vinyl record, thus simulating the complete functional capability of a traditional record deck and vinyl record in a compact disc player.