Many 3M Littmann stethoscopes have a tunable diaphragm.  This guide will help you understand this technology.

Tunable technology provides convenience, versatility and enhanced acoustics. The dual frequency diaphragm combines both bell (low-frequency) and diaphragm (high frequency) into a single side of the chestpiece. You control bell and diaphragm modes by pressure on the chestpiece rather than by turning it over.

Bell Mode (Low-Frequency)

For low-frequency sounds, light contact is used on the chestpiece. The diaphragm membrane is contained by a flexible surround that actually suspends it, allowing the membrane to resonate low-frequency sounds.

Diaphragm Mode (High-Frequency)

For high-frequency sounds, firm contact pressure is used on the chestpiece. By pressing on the chestpiece, the diaphragm membrane moves inward until it reaches an internal ring. The ring simply restricts the diaphragm membrane's movement. It blocks, or attenuates, low-frequency sound and allows you to hear the higher frequency sounds.

Summary

3M's tunable diaphragm technology ensures that your Littmann stethoscope's performance is of the highest quality and efficiency available.  Be sure to visit our eBay store for a great selection of Littmann stethoscopes at affordable prices.  Also, see our other guides for more information about Littmanns.