Headphone Sensitivity & Impedance

As a consumer, it is important to be conscientious about the products you are looking to purchase to get the best quality for your intended purpose of use. While searching for the right headphones, whether in stores or online, it is essential to carefully review the product descriptions and technical specifications of the many different brands and models that are out there. One influential aspect of the overall quality you will see is the sensitivity level of the headphones.  Free Fun Guides has some great Headphone Buying Guides with a lot of information if you’re looking for specific models.

What is Headphone Sensitivity?

There are a few things that you need to keep in mind while selecting headphones. One of the essential electrical characteristics of headphones is their sensitivity. Headphone sensitivity measures how efficiently an earpiece can convert an incoming electrical signal into a clear, perceptible sound. Sensitivity denotes how loud the headphones will be for a given level from the source. Sensitivity works hand-in-hand with the impedance of the headphones. They must correspond to each other because they both work hand-in-hand to regulate sound and produce clear acoustics without distortion.

How is Headphone Sensitivity Measured?

The output of the headphone is calculated in decibels of the sound intensity level per milliwatt (dB SPL/mW). It may often be seen as dB/mW, based on an input signal of 1 mW. Typically, the sensitivity of the earphones is between 80 and 125 dB SPL/mW. To set these figures in a better context, 80 dB is equal to the sound of heavy street traffic from 25 to 50 feet away, while 125 dB is similar to the sound found in the diesel engine room. It should be remembered that at 120 dB, the human ear starts to replace the sense of hearing with the sensation of pain.

Finding the Best Headphone Sensitivity for Your Audio Device

It is useful to consider this basic specification of the headphones in order to choose the ones that will fit better for your audio system. You must first consider the power output of the unit when deciding the correct headphone sensitivity level for your audio device. As the headphones are over your head and are very close to your ears, you need to achieve a good equilibrium to maintain tolerable conditions for your ears to be able to tolerate while achieving the highest sound quality comfortably.

Focal Listen Headphones

If you have a headset with a lower output frequency, you may want to avoid using low-sensitivity headphones. Combining a lower output unit with a low-sensitivity earphone will result in a low SPL/mW, which will cause the audio to sound distorted the higher the frequency of the amplifier. This can lead to what is known as the clipping of the amplifier, which is where the amplifier fails to produce peak voltage or current above its full potential. When using high-sensitivity headphones or high-powered devices, you will also hear unwanted noise and loss in audio quality.

The higher the sensitivity level, the better your headphones adapt to a wide range of power outputs without needing ultimate power for effective sound. The downside to high sensitivity, though, is that headphones can not sustain a lot of violence, such as listening to high degrees of distortion. Headphones with lower sensitivity need more fuel, which forces you to give them the maximum potential to achieve optimum efficiency. The advantage of low sensitivity is that they are more difficult to destroy than those of higher sensitivity.

Any of the studio equipment used for recording and post-production has a medium to high power output. It will be preferred to exclude the risk of distortion by using a low-sensitivity or lower-dB SPL/mW headset. However, most smartphones, laptops, and mp3 players have poor power outputs since they only run on battery power. It would be best for these types of systems to use dynamic headphones with a sensitivity of at least 90 dB. Using the wrong headphones with too little sensitivity for a handheld computer will allow the loudness to be compromised, and you will need to turn the volume too much as you listen. Not only will the sound quality suffer, but this can cause your battery life to become consumed quicker.

Headphone Impedance

When you go through the various selections of headphones available on the market today, it is important to look at the specification of the items you are considering purchasing. Only because a collection is popular or has positive ratings doesn’t always mean that it’s perfect for your needs.

What Is Headphone Impedance?

When you look at the labels and cases of your headphones, one of the technological features you’ll still find is impedance. This refers to the frequency or sound quality of your headphones as they are wired into audio equipment. Impedance is how much power or voltage the headphones need to operate. The higher the impedance of the headphones, the higher the voltage requirement. On the other hand, lower impedance headsets need less power.

Years earlier, high impedance headphones were pretty much normal, so most music and entertainment systems were not portable. Headphones were often used for home stereo or specialist recording studios. Due to the lack of battery capacity, high impedance headphones were not a big concern. The 1980s headphone jacks had a very high output impedance corrected by large resistors that regulated the power output from the speakers.

Headphone Impedance for Mobile Devices

Today, headphones are used in-studio with professional equipment and portable entertainment devices such as iPods, laptops, mp3 players, portable DVD players, and smartphones. People like to have their music and movies on-the-go with them, but they also want to fully enjoy and be immersed in the listening experience, especially when traveling.

High impedance headphones will use up more battery life, which can be a priority for mobile listeners. Battery-powered devices do not typically work well with high impedance headphones. If you are mostly using your headphones on-the-go, you want to keep an eye on the impedance.
It is important to remember that impedance has nothing to do with the weight of the headphones. Many people unnecessarily make the connection between impedance and weight, incorrectly assuming that if a pair of headphones is lightweight, then it must be low impedance. This is not always the case, though.

Normal Headphone Impedance

Impedance in headphones ranges from as low as 16 Ohms to as high as 600 Ohms. If you will be using your headphones mainly for portable devices, it is recommended to stick to headphones within the range of 16-32 Ohms. As a general rule, lower impedance headphones are a better match for portable devices. Many motherboards, particularly in newer appliances can handle the impedance of up to 64 Ohms, as long as the volume is only turned up to about 3/4 of full volume.

European-made portable music players and smartphones that conform with the European Maximum Volume Regulations normally have maximum output relative to other handheld devices, but you will need to find headphones that remain within the 16 Ohm range.

A safe rule of thumb is to stop any headphones that have an impedance of more than 100 Ohm for portable music players. These headsets are not usually intended for smartphone use. They are best suited for recording studios or home stereo setups.

Headphone Frequency Response

Frequency response is one of the technical specifications of headphones that you will see listed on labels and in product details. It refers to the headphones’ capability of reproducing audio frequencies. In more technical terms, it is the speed of vibration of physical materials or components. Frequency response is measured in Hz. Inside the headphones are the drivers, and these drivers have a range in which they can translate clear sound to the user’s ears.

What is Normal Frequency Response?

Sound flows in the frequency band. You will also read or hear headphone fans and bloggers complaining about tops, mids, and lows. These words apply to the frequencies at which the sound passes. The bass sounds are at the lower end of the scale, while the treble sounds travel at the upper end of the spectrum. The typical frequency range for most of the headphones you’ll see these days is 20 to 20,000 Hz. This is what is accepted as the audible frequency spectrum, ensuring that the sound is balanced.

You’ll note some of the headphones that are sold have larger frequency ranges and probably better frequency responses. Better frequency response, however, would not necessarily equal better sound quality. In reality, even if your headphones have a better frequency response, if other things like impedance just don’t work, it won’t make much of a difference.

Frequency Response for Different Genres

If you’re looking for a headphone that can help you feel the rhythm in your chest and make your heart dance with music, you’re better off having bigger headphones that give priority to lower frequencies. If you use these headphones to get a deeper, cleaner bass tone, natural execution and accuracy and separation of the instrument will be sacrificed.

Compare your headphones to the usual frequency response, and you’ll be able to get a general sense of how they behave at low, mid, and high frequencies.