What Impedance Can the iPhone Drive? – All You Need To Know

Choosing the right pair of headphones for your mobile phone is not as simple as you might think, and impedance is a large part of the equation.

We’ve found that 250 Ohms is the maximum impedance value to provide a comfortable listening experience on your iPhone. Anything higher than that, and you’ll get much lower sound levels unless you use a dedicated amplifier. 

This article will shed some light on the subject of impedance. We will explain what it is and why you need to consider it when choosing your next pair of headphones.

Apart from showing you the maximum impedance an iPhone can drive, we’ll also tell you the minimum and optimal values.

What Is Impedance?

To understand why you need to follow headphone impedance rules, you first need to know what they are. In a nutshell, impedance is the resistance to the flow of alternating current.

A high impedance rating means electricity will have difficulty passing through your cans. On the other hand, low impedance means that the headphones will allow electricity to flow through them more freely.

We measure impedance in Ohms. Headphones come in all varieties – from low impedance ones going down to 8 Ohms, to high impedance, which starts at around 100 Ohms. High-end audiophile headphones can even have a rating as high as 600 Ohms. 

What if the Impedance Is Too High or Low?

Tech jargon aside, high impedance headphones require a more powerful amplifier to work correctly. Therefore, if we assume you’re using the same phone, the higher the impedance, the lower the output signal.

So, for example, with most phones, iPhones included, using 600 Ohm headphones will not produce sufficient volume, even if you set it to the max.

A very low impedance rating can also be a bad thing. In theory, if your cans’ impedance is lower than your iPhone can handle, its amplifier will get too hot and, at worst, burn.

However, this shouldn’t be a problem with modern iPhones, as they can drive most, if not all, low impedance headphones.

What Impedance Is Right for an iPhone?

iPhone Model	Headphone Output Impedance	Recommended Headphone Impedance Range
iPhone 15	1.4 ohms	14-140 ohms
iPhone 14	1.6 ohms	16-160 ohms
iPhone 13	1.8 ohms	18-180 ohms
iPhone 12	2.0 ohms	20-200 ohms
iPhone 11	2.2 ohms	22-220 ohms

Nowadays, most mobile phones come with an amplifier that works best with 32 Ohm headphones. Luckily, most consumer-grade headphones also fall into the 32 Ohm category.

That means you shouldn’t have difficulty choosing your next pair of cans. However, better-quality ones sometimes come with a higher impedance rating.

What is the Highest Impedance an iPhone Can Handle?

Right off the bat, let us say that you can forget about using 600 Ohm studio cans with your iPhone or any other phone.

This is because their built-in amplifiers are not powerful enough to drive such complex audio gear. However, there are a lot of solid choices that fall below that Ohm rating.

Some of the most famous enthusiast-grade headphones fall into the 250 Ohm category. While that’s still a very high rating, our tests show that iPhones have little trouble driving the average pair of 250 Ohm headphones.

That goes for the last couple of generations; the iPhone 8 and all newer iPhones are perfectly capable of putting out adequate sound levels when matched to a 250 Ohm pair.

In fact, the iPhone 8 has a beefy headphone amplifier, and in some cases, it will even drive a pair of 600 Ohm cans.

What About Low Impedance Headphones?

As with most mobile phones currently on the market, the low impedance is rarely a problem for the iPhone.

Current iPhones can easily drive any headphones down to an 8-Ohm impedance. We’re not sure if they can go lower, but that’s because there are no such headphones currently available.

However, that doesn’t mean you shouldn’t be careful. There’s a reason why Apple recommends that you stay around 32 ohms. If you plug a pair of 8 Ohm headphones into your iPhone, it will probably drive them to painfully loud levels.

Be especially careful with in-ear headphones; high sound pressure levels delivered directly into your ears might cause permanent damage to your hearing.

What if I Want to Use Large Studio Headphones With My iPhone?

Most large studio headphones have an impedance level of around 600 Ohms, and some even go higher.

Such a high rating means that your iPhone will not be capable of driving them on its own, and even if it does, it’s bound to introduce some distortion to the sound.

If you’re using headphones that are hard to drive, you will need a dedicated headphone amplifier. An amplifier is an external device that sits between your iPhone and your headphones, providing the phone’s signal with a power boost.

This device does the job usually done by the iPhone’s internal amplifier.

Headphone amplifiers come in all shapes and sizes. Mobile, battery-powered ones are probably the best choice to use with an iPhone; that way, you can listen to your high-end headphones on the go.

However, if you want a very high-quality listening experience, a desktop amplifier will do an even better job.

Related Questions

Is it possible to damage anything by choosing the wrong impedance?

Not really. If you plug a pair of ultra-high impedance headphones into your iPhone, the worst thing that can happen is a muted response.

On the other hand, as we mentioned earlier, extremely low headphone impedance can burn an amplifier. However, that shouldn’t concern you, as the latest iPhone models can quickly drive the lowest impedance headphones available.

Does higher impedance mean better sound quality?

Not at all. As we explained, impedance is a way to describe some of the properties of an electrical circuit and is not directly related to sound quality.

Most studio headphones have higher impedance ratings because of their more robust drivers, making it harder for current to pass through.

The market offers a wide selection of 32 Ohm headphones, and many of them produce excellent sound quality. Since mobile audio is so popular right now, many manufacturers make a low impedance version of some of their studio headphones.

Is impedance the only thing that controls how loud my headphones are?

No, there’s also something called headphone sensitivity. We can roughly define this quality as the increase in sound pressure levels per one watt of power delivery.

As a result, even if two headphones have identical impedance ratings, they can deliver different sound output levels. Because you don’t know if you’ll get enough sound, you should test your cans before buying them if you’re unsure.

Conclusion

We can safely say that the last few iPhone models do an excellent job of driving 250-ohm headphones. Unless you choose the least sensitive ones, your iPhone will quickly drive them to comfortable listening levels.

If you want to use headphones with an even higher impedance, you can—you only need an external headphone amplifier. You can choose between a mobile and a desktop version, depending on how you use it.

When it comes to low-impedance headphones, volume is the only thing you need to consider. As impedance goes down, sound pressure levels go up, damaging your hearing.