8 Parts Of A Stethoscope | Detailed Guide Of Its Uses and Function

With the help of a stethoscope, one can hear the sounds of the body of a patient. Medical professionals use their stethoscopes to obtain sounds that allow them to diagnose a patient’s illness or condition. Here we will discuss Parts Of A Stethoscope

A healthcare professional cannot imagine life without a stethoscope. Medical professionals spend a lot of time with their stethoscopes, so choosing one is not a decision to be made lightly.

Basically, you place the head or chest piece of the stethoscope against the patient’s chest, stomach, or back, thus picking up sounds from these areas. The stethoscope tube transmits the sounds to the ear tubes, where they can be heard, as well as the heartbeat and lung sounds of the patient.

Therefore, one should be aware of the parts and functions of a stethoscope in order to use it properly. Additionally, you will be able to manage the stethoscope effectively. A stethoscope has several components, including a chest piece, diaphragm, bell, stem, tubing, headset, ear tubes, and ear tips. Now let’s look at each component in more detail.

Parts Of A Stethoscope and its function

There are basically seven parts to acoustic stethoscopes. Namely, the chest piece, stem, diaphragm, bell, ear tubes, headset, and ear tips. Down below, you will get the complete detail of these parts and their function. 

  • Chest piece part

It detects, captures, and transmits sounds

The chest piece also called the head, conducts sound through the body of the stethoscope. An acoustic stethoscope’s chest piece is perhaps one of its most crucial components. Since it detects, captures, and transmits sounds from the body to the headset, it plays a vital role in the process.

As the name suggests, the chest piece is placed against a patient’s skin.

Due to technological advances, many stethoscopes can now conduct sound through clothing, bandages, blankets, and even animal fur.

One-sided chest piece

There are two types of chest pieces on stethoscopes: one-sided or two-sided. Several stethoscopes will have just diaphragms if they have one-sided chest pieces. Diaphragms can also act as bells and diaphragms, as some stethoscopes have tunable or pressure-sensitive diaphragms. 

Two-sided chest piece

On the other hand, those with two-sided chest pieces have a bell at the top of one side and a diaphragm on the other. Users can rotate the chest pieces to choose whichever side is most suitable for diagnosing. 

Stethoscopes used with chest pieces are typically made from metals; however, acrylic head stethoscopes are also available, which are excellent at blocking out ambient noise. The diaphragm, bell, and stem make up the chest piece. 

In the following section, we’ll learn more about each element. The differences among the designs provide healthcare providers with unique benefits that boost their listening experience.

Chest piece functionality

 Whenever the chest piece is placed on a patient’s chest, back, or stomach, the diaphragm or bell listens to their sounds. Through this, the device can tune into specific noises such as heartbeats, lung sounds, arterial blood pressure, and other human sounds.

Change the frequency by pressing the chest piece

 By pressing the chest piece, you can change the frequency of the acoustic. So, healthcare specialists can make a better and more accurate assessment of the severity of specific sounds.

Place it on bare skin for accurate results

Direct application of chest pieces against the patient’s skin in the right location generally leads to the best results. Medical professionals can detect even the faintest noises with high-end electronic stethoscopes, which amplify sound.

Such stethoscopes are vital for individuals working in the fields of cardiology and emergency medicine.

  • Diaphragm 

Listen to broader areas of bodies

The diaphragm is the large round section at the center of the chest piece. A chest piece with a two-sided diaphragm will have the larger end. Because of its larger size, it is possible to listen to a broader area of the patient’s body parts. Furthermore, it is better suited to picking up adult sounds than the bell portion of the chest piece.

It picks up higher frequencies 

Diaphragms are designed to pick up sounds that have a higher frequency than bells. Thus, this part is utilized mainly for monitoring adult bodily sounds by nurses, doctors, and healthcare specialists. 

Non-chill construction

In today’s modern diaphragm, the chill is removed from the patient’s skin, and it has better hypoallergenic properties, resulting in greater comfort and safety for the patient. Also, this allows the device to directly contact the skin without creating discomfort or a cold reaction.

  • Bell

On the chest piece, there is a smaller circular end known as the bell or pediatric side. This area allows listeners to hear the vital signs of infants and pediatric patients in a more focused manner.

Listen to low frequencies 

It has a more restricted frequency range with a smaller diameter, focusing on lower frequencies than the diaphragm. In much the same way as the diaphragm, today’s bells offer features that make examinations more comfortable for patients.

Observe and detect small bodies

As a result, the bell provides an ideal situation for monitoring, observing, and detecting sounds coming from little bodies. Additionally, the bell may be hypoallergenic and non-chill, so you’ll be comfortable listening to it. In the carotid area or with bandaged areas, the bell is used as well. 

  • Lumen Tubing 

Flexible rubber material 

Transmission and relay of frequencies or sounds are accomplished via the tubing. So the user can hear the sounds, the tubing directs the sounds to the ear tubes. The lumen tubing connects the chest piece to the headset with a flexible, soft rubber/PVC material.

Single tubes and dual-lumen tubes

Stethoscopes are usually available as either single tubes or dual-lumen tubes. The dual lumen tubing consists of two overlapping sound channels inside one outer tube that is actually half split on the inside. Thus, a left-right path is created to ensure the user’s ears receive the sound with maximum accuracy. 

It depends on how the tubing is designed by the manufacturer, stethoscope design, and chest piece/headset.

They are durable

Stethoscope tubing nowadays can withstand skin oils as well as alcohol, so they will last longer and will be easier to clean.

  • Stem

Made Of Steel And Metal 

Stethoscope stems connect the chest piece to the tubing of the instrument. The stems are usually metal or steel, which ensures an optimal connection for the best performance.

 The stem also provides access to the diaphragm and bell on the stethoscope on chest pieces with two sides. The chest piece can be rotated and then clicked into place with a ball bearing. You can control whether sounds are directed to the ear tubes via the diaphragm or the bell by rotating the chest piece.

It lets you remove, replace or access the chest piece

Last but not least, the stem lets the user remove the chest piece, repair it or swap it if necessary. Whenever you need to replace components that are damaged or access alternative attachments for assessing your patient’s condition, it is essential to remove them.

  • Ear tubes 

Stethoscope tubing connects to ear tips through ear tubes. Ear tubes are of metal stud or steel piece to be at the optimal angle in order to maximize the amount of sound that reaches a user’s ear canal. 

It provides a clearer listening experience. 

The sound is isolated and directed in the left and right direction through the ear tubes, providing a clearer listening experience for doctors and facilitating diagnosing their patients’ medical conditions. 

Efficient acoustic design

Ear tubes include ribbed ends at which the ear tips are attached. An ear tube that uses premium components and an efficient acoustic design will ensure a minimal sound quality loss. In addition, they provide ample comfort by adjusting the ear canal angle appropriately.

  • Ear tips 

In addition to providing a seal inside the ear, the ear tips are also comfortable to wear. Sounds can thus reach the air channel well and quickly. Moreover, it prevents external noise from interfering with listening to the patient’s heart, lungs, and other bodily sounds.

Complete seal

Stethoscopes would leak out unwanted sounds if they did not have quality ear tips, resulting in an unpleasant listening experience. Ear tips comprise rubber or silicone material, which forms a seal inside the ear.

Comfortable fit

These devices fit comfortably inside the ear canal, so users can handle constant measurements without experiencing any discomfort. In this case, users who spend a lot of time checking the health of patients need an ear tip that is comfortable for them.

Soft and flexible material

All modern ear tips are constructed from soft, flexible materials appropriate for fitting inside and cradling the inner ear. Through the center of the binaural, sound easily transfers to the ear tips. Furthermore, the inside of the ear tips features a smooth or rigged surface where ear tubes meet ear tips. 

To improve one’s experience with their stethoscope, one of the easiest things to replace is the ear tips. It’s inexpensive and easy to replace the ear tips.

  • Headset 

In other words, it can be viewed as part of the stethoscope when it is worn over the neck of a healthcare professional. Furthermore, the headset comes with springs and ear tips. These components ensure a comfortable fit for the user’s ears, which facilitates sound transfer and quality.

Excellent angle for a perfect fit

Therefore, it is of the utmost importance to ensure that nurses, doctors, and other healthcare professionals are receiving the best performance from their headsets. When viewed from the side, the ear tips of the headset point toward the user’s nose, which is contrasted with slightly backward ear tubes. Thus, the headset is angled in such a way as to be perfectly suited to your head. 

Improves comfort

The stethoscope’s sound can pass through to the ears efficiently, minimizing disturbance. Likewise, it enhances comfort and aligns the ear tips with the ear canal in order to improve sound performance.

All of these elements provide comfort, support, acoustic properties, and sound transfer.

Cleaning The Parts Of The Stethoscope

For the stethoscope to last, it is crucial that you take care of and maintain it. Moreover, cleaning the parts of your tool provides you optimal performance and keeps you and your patients disinfectant. 

Regular cleaning is the best form of care and hygiene, which will prevent your stethoscope parts from breaking down. Here, I’m providing you with some guidelines and tips to keep your stethoscope maintained. 

Wipe your tool with an alcohol solution

To clean a stethoscope, wipe with soapy water or alcohol wipes cleaning wipes. Allow drying thoroughly in a clean place. Tunable diaphragms should be removed from the chest piece before doing this and wiped down separately.

 Stethoscope ear tips should also be removed using an alcohol solution or soapy water as part of good stethoscope cleaning practice. Keeping your stethoscope clean can get rid of bacteria quickly and easily, which is especially important if you share your stethoscope with others. It is no fun to get an ear infection, after all.

Disinfecting your stethoscope 

Sterilizing your stethoscope is as easy as wiping it down with 70% isopropyl alcohol or using a dedicated device. Sterilization methods that involve autoclaving or steam sterilization should never be attempted with stethoscopes. Additionally, the instruments should never be a dip in liquid. 

 In addition, never use solvents, oils, hand sanitizer, or non-alcohol-based cleaning solutions, as these may damage delicate parts of your equipment while cleaning your stethoscope. 

The Care of a Stethoscope

While it is sometimes tempting for students to skimp on the maintenance of their stethoscopes when it comes to spending money on new equipment, they quickly regret not taking the time. Although, no matter how you care for your stethoscope, whether it’s a high-end student model or an entry-level model from 3M Littman, caring for your tool is essentially the same. 

Stethoscope Tubing Care

Keep your instrument away from oils.

Tubing for stethoscopes is typically made from PVC. The PVC material hardens when exposed to the oils on our skin or to direct sunlight for prolonged periods of time, making the material increasingly brittle. 

Put your stethoscope under a shirt collar if you’re wearing it around your neck so that it doesn’t come in contact with your skin or exposure to the sun for long periods.

Furthermore, bacteria do not transfer from the skin to the stethoscope as well as the other way around. 

Do not squeeze the tubing.

If you are the type of person who folds your stethoscope tight to fit into an already bulging pocket, it can crack the tubing that leading to leakage. While this is more common with lower-cost brands of stethoscopes, even Littmann stethoscope tubing should not be taken for granted. It also requires care and maintenance. 

Keep your instrument away from extreme temperatures.

No matter what kind of stethoscope you have, you must avoid extreme heat, cold, solvents, and oils because they can harm the tubing and other delicate parts like the diaphragm, the head, and the rim assembly.

Additionally, you can prolong the life span of your stethoscope by storing it in a box or carrying a case instead of throwing it on the floor. 

Replacing parts of your stethoscope

Along with cleaning the parts, diaphragms, rims, and ear tips must also be replaced when damaged or do not provide accurate results. You can replace the parts instead of throwing away your device.

Some models come with replacing parts with different sizes of ear tips. 

Additionally, it would be best to remember that many of the more affordable models don’t sell spare parts.

How to remove and assemble the tunable diaphragm?

To remove the tunable diaphragm, pinch the rim of the Littmann tunable diaphragm with your thumb and index fingernails; then, lift and remove the diaphragm from the chest piece. 

To reassemble the Littmann tunable diaphragm, remove the non-chill bell sleeve. Roll the rim slowly around and over the edge of the chest piece by inserting the flexible edge of the tunable diaphragm into the groove of the rim.

Convert the tunable diaphragm to the traditional bell

With the addition of the Littmann tunable diaphragm, the small side of the chest piece can be used or can be converted into a traditional open bell with the non-chill sleeve that comes with the product. More importantly, assemble the non-chill bell sleeve by placing one side of the sleeve at the edge of the chest piece and stretching it across the edge. 

How To Hold And Wear A Stethoscope In A Right Way?

Newcomers to the medical field may struggle to understand how to wear their stethoscopes correctly. Furthermore, here are some tips for wearing a stethoscope effectively in the following paragraphs. 

Place your earpieces in the correct position

It is essential to place the earpieces properly on the stethoscope before using it. Be gentle when inserting the earpieces into your ear canals. Twist the tips slightly forward so that they point toward your nose.

By doing so, you can establish a tight seal, allowing you to focus on the stethoscope’s transmission of sound. In an adequately positioned earpiece, the ambient noise in a room should be barely audible.

Many stethoscopes come with an assortment of ear tips in different sizes. Trying the additional ear tips will help you find the most comfortable pair of earpieces and provide the best seal.


Holding the chest piece appropriately

You can create extra noise when you hold the stethoscope’s chest piece incorrectly, which makes auscultation more difficult. Using a stethoscope properly will enable you to hear all sounds crisply and clearly. Consequently, your dominant hand should be used to hold the chest piece between your ring and middle finger.


It is not a good idea to grip the chest piece with your fingertips since this can create a lot of unwanted noise. Moreover, it is a good idea to hold the tube with your thumb so that it doesn’t rub against the skin.

By applying gentle pressure to the chest piece, you will maximize its sound transmission. However, if you are in a hurry, you can wear the chest piece over thin clothing. In fact, rubbing your clothing against the diaphragm is more likely to cause noise. And you might end up missing subtle sounds that are crucial.


How To Carry Your Stethoscope When Not In Use?

When stethoscopes are not in use, most healthcare professionals wear them around their necks. An ideal stethoscope will be well-balanced and stay in place despite its weight.

However, whenever possible, you should position the tubing over your shirt collar to prevent the tubing from hardening due to oily skin. If you wear clothing that rubs against your chest piece, the fitting can become loose, so you must check that the chest and earpieces stay tight.

Additionally, it would help if you didn’t tuck your stethoscope into your scrubs or lab coat pocket. As a result, the tubing, and earpieces can twist in ways that they weren’t meant to, which can cause seals to loosen or kinks to form in the tubing that can interfere with sounds. 




Photo of author

Muhammad Bilal Qayyum

MBBS from Taishan Medical University and currently working in Bahawal Victoria Hospital. The blog is a great resource for both novices and experienced users when it comes to stethoscopes. As I studied and practiced, I evaluated various models on the market, which led me to become an expert in stethoscopes.

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