Home Donate New Search Gallery Reviews How-To Books Links Workshops About Contact (12.9″ diagonal, 4:3 aspect ratio, 264 DPI 2,732 × 2,048 Retina display, 10 hour battery life, 24.735 oz./701.3g, $800 ~ $1,080.)
These are measurements of the 3.5mm analog audio output of my iPad Pro playing signals in its Music app. Few people realize that Apple iOS devices have some of the best audio digital-to-analog converters and low-impedance headphone amplifiers available at any price.
Here are some quick measurements of my iPad Pro made in my laboratory with a state-of-the-art Rohde & Schwarz UPL audio analyzer. Higher output source impedances lead to frequency response imbalances caused by the varying real impedance of actual headphones with frequency, and also leads to low-frequency distortion when driving real headphones. The ultra-low output source impedance of the iPad Pro is so low as to stop any of these potential problems 0.002% THD and harmonic distortion components at 1 kHz at 0 dBFS into 200KΩ at maximum output level.
0.005% THD and harmonic distortion components at 4 kHz at 0 dBFS into 200KΩ at maximum output level.
0.002% THD and harmonic distortion components at 31 Hz at 0 dBFS into 200KΩ at maximum output level. 0.002% THD and harmonic distortion components at 1 kHz at 0 dBFS into 300Ω at maximum output level. The THD driving 300 Ω is just as low as into 200kΩ and harmonic distortion again is mostly second-order, just like a tube amplifier.
0.005% THD and harmonic distortion components at 4 kHz at 0 dBFS into 300Ω at maximum output level. 0.006% THD and harmonic distortion components at 31 Hz at 0 dBFS into 300Ω at maximum output level.
0.125% THD and harmonic distortion components at 31 Hz at 0 dBFS driving the 32Ω beyerdynamic T51i headphones at maximum volume setting. 0.017% THD and harmonic distortion components at 31 Hz at 0 dBFS driving the 32Ω beyerdynamic T51i headphones at -20dB volume setting.
This is excellent real-world performance — which few portable audiophile products can match at any price! For enjoying music, you will probably get poorer performance if you waste your time and money with outboard DACs or headphone amplifiers; the iPhone already has the best there is. As this page is copyrighted and formally registered, it is unlawful to make copies, especially in the form of printouts for personal use. Home Donate New Search Gallery Reviews How-To Books Links Workshops About Contact
Can you use headphones on an iPad Air
If your iPad model does not have a 3.5mm Headphone jack, you can use an appropriate adapter that includes a suitable DAC (Digital to Analogue) converter.
What Does Ohm & Impedance Mean In Earphones/headphones?
Ohm, on the other hand, is the unit of measure for impedance, which is the property of an earphones/headphones that restrict the flow of electrical current through it. Does it even matter for music lovers to know about it or it’s just like one of those artistic paintings that makes your dining room more beautiful but never pays attention to that piece of art?
Having certain kind of knowledge about it is important, otherwise, you’ll never know that you might not get the best sound quality from headphones with impedance which is too high or too low for your music player. Firstly, the impedance of a headphone is determined by the design of its voice coils – the length & size of wire used, the number of turns around the former & so on. Henceforth, these are designed for pro studio applications which allows them to consume the required power to outsource the hi-fi audio. The only drawback with this kind of headphones impedance, it can not be used with a powerful amplifier because of their low threshold limit, otherwise, one has to face the blowout.
Test report a newbie-dummies Reference Audio Analyzer
High sensitivity of the headphones means less energy need from the source (for portable devices – less power from the battery). For noisy environments, an amplifier with a voltage level of at least 4.04 dBV at a load of 42.20 ohms is desirable.
iPad mini retina and iPad Air sound quality and impedance output
Check that it’s updated, the file quality, and that no EQ etc is engaged.
Use high-impedance headphones with MacBook Air, MacBook Pro, or Mac Studio
With impedance detection, adaptive voltage output, and a built-in digital-to-analog converter that supports sample rates of up to 96 kHz, you can enjoy high-fidelity, full-resolution audio directly from the headphone jack on your Mac.
Measurement’s report Apple iPad mini
Measurements of Apple iPad mini were carried out by Roman Kuznetsov on the hardware-software complex RAA.
Headphone Impedance Demystified: Do I Need a Headphone Amp? |…
Impedance is one of the basic specifications included with almost every quality pair of headphones and most audio sources (DAP, phone or amplifier). For the sake of simplicity, this article will be limiting itself to examples using headphones rather than IEMs or ear buds, but the basic concepts remain the same. Headphones are different than home stereos, as speakers are commonly in a very narrow range between 4-8 ohms. “The single most important technological factor to consider when looking for a headphone amplifier that works well with your ear phones is impedance matching.” – RHA Audio Equal source and load impedance maximize the power we can transfer between the amp and headphones, but this typically reduces frequency bandwidth so it’s not what we want in high fidelity. Conversely, high impedance headphones (50 ohms and greater) usually require robust amplification to perform their best.
Headphones with impedance greater than 100 ohms are typically older or professional studio specific designs. Pre-1990s receivers and pro audio equipment often used resistors to attenuate the speaker output power (wattage) to create a simple and inexpensive headphone circuit.
In some cases, high impedance headphones were designed to chain multiple pairs in parallel for pro studio applications. Without getting too heavily into the math behind it, the high impedance load preserves the source output voltage to be able to drive multiple pairs of headphones. Most modern headphones are designed to appeal to as wide a market as possible, and that means they must play well on mobile devices. The sale of hundreds of millions of battery powered music players, including the ubiquitous iPod and more recently smartphones, has made lower impedance (around 32 ohms) headphones the norm.
If properly matched to an appropriate amplifier, it is possible to achieve an enhanced quality of sound with high impedance headphones, at least with specific designs like the Beyerdynamic models above. It would appear, with comfortable listening volume levels of 60-80 dB, a full 1 mW of power should seldom be required to achieve more than adequate loudness.
We also need to take into account music dynamics and our amp’s total harmonic distortion (THD).
“Impedance… is more complex and measured with an AC current… Because music is an alternating signal, not DC, impedance is how headphones are rated.
They’re what’s known as a reactive load and the math is considerably more complex than just the most basic form of Ohm’s Law.” – NwAvGuy (an anonymous engineer who created excellent and controversial DIY audio designs such as the O2 headphone amplifier ). To further complicate things, there is little consistency in headphone design with regards to impedance and sensitivity (even within a single manufacturer). From the following chart listing a variety of headphone models with a range of impedances, it is easy to see many different sensitivities. The voice coil in dynamic headphones is designed to properly control the driver and ensure good behavior at its resonant frequency.
They use an S-shaped pattern for the voice coil (unlike traditional circular windings) which tends to yield a low impedance.
Conversely from the same company, the HifiMan HE-6 is notoriously inefficient and difficult to drive (50 ohms – 83.5 dB). Planar magnetic and dynamic headphones of similar ratings will often have quite different amplification requirements. This can result in poor control of the driver (damping), and possibly audible distortion at those frequencies.
Sometimes these variations can be large and plainly audible.” – NwAvGuy For instance, many Sennheiser headphones have an exaggerated frequency spike around 100Hz. The Sennheiser HD6xx line can require high voltage (3-6V) at the spike, making it a poor pairing for many lower-powered mobile devices, but an ideal match for the Bottlehead Crack OTL tube amplifier characteristics (120 Ohm output impedance and high voltage). This drop can be large to enough to prevent driving low impedance headphones to sufficiently loud levels.
Equal impedance between source and headphones is good for portable power requirements, but not necessarily for sound quality.
While it is extremely unlikely that anything catastrophic or destructive will occur with headphone and source impedance mismatches, sound quality can suffer. Call it matching, pairing, synergy or just a case of plain old BFF, the source and the headphones must complement each other.
While often only found in the extremes of OTL tube amplification, this scenario creates higher harmonic distortion and noise, a low damping factor, and bass roll-off. For every rule and scientific explanation you can read, it is easy to find contrary subjective user experiences that claim great success and impeccable audio performance against all odds.
“…higher impedance headphones also require less current to drive and that typically reduces distortion in multiple ways.
This results in bigger mismatches and creates more variation from the headphone’s default sound signature .
Low damping factor is commonly associated with bass ‘bloom’ or ‘boom’ around the headphone’s resonant frequency. The bass performance of the headphones, as designed by the manufacture[r], may be audibly compromised if there’s insufficient damping.
Balanced and unbalanced are types of interconnections between devices (like an amp and a headphone); these terms do not refer to specific amplifier architectures. Impedance matching between headphone and source is done to ensure a good combination of sound quality and sufficient volume. This recommended ratio is commonly known as the ‘rule of eighths’ and contributes to proper driver control (damping factor). Pairing a headphone with an equal or lower impedance than the source will likely result in unpredictable (poor) sound quality.
Sensitivity is also an important factor in headphones, and is a measurement of loudness at a certain power input (usually given as decibels per 1 mW). Sensitive (100 dB+), low impedance (8-32 ohm) headphones will typically pair well with a portable source (such as a phone) without much benefit from a separate amplifier.
Less sensitive (less than 95 dB), and/or medium to high impedance (more than 50 ohm) headphones will typically benefit in sound quality and volume with a more robust amplifier than a phone (or portable device) provides. This means it will always deliver the same output into any load.” Since we live in the land of compromise rather than perfection, we have to make educated decisions when selecting an amplifier for our headphones.
Luckily, there is almost a guarantee that someone out there has tried and written (or YouTubed) about their experiences with the combination of headphone and source you are considering.
Optimal Headphone for iPad?
Let’s say I want the best headphone possible for my iPad to play with synth, can i just close my eyes, buy a very expensive pairs of headphone and expect good result? With my computer, I use headphone to watch documentary on Netflix.
What is the impedance of the line/headphone jack on MacBook Pro Retina?
I couldn’t find the specific details for the original MacBook Pro Retina machine, but these specs are pretty universal across the whole MBP lineup and should help you match a pair of headphones: I did find a link on the Apple Support page that says the Mac Mini’s headphone jack is 10 Ohms.
Apple Provides Details on Using High-Impedance Headphones With New MacBook Pros
As noted in the support document, the new MacBook Pros come with DC load detection, adaptive voltage output, and a built-in digital-to-analog converter. With impedance detection, adaptive voltage output, and a built-in digital-to-analog converter that supports sample rates of up to 96 kHz, you can enjoy high-fidelity, full-resolution audio directly from the headphone jack on your MacBook Pro.
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