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Review: Apple vs Google USB-C Headphone Adapters

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There is an EU law which requires portable audio devices to restrict volume levels to 85 dB SPL. Many Android devices (including iPhones?) have different gain settings for EU and non-EU markets.
I don't think it's EU law - from what I found, only France has a law about this, and it seems to only apply to devices that ship with headphones (i.e. it would apply to the combination of a smartphone with bundled headphones, but not to an audio device sold without headphones). Which is fortunate, because otherwise, according to EN 50332-2, the limit for an audio device sold without headphones would be 150 mV, which would surely mean most devices sold on the French market would be illegal!
 

Veri

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I don't think it's EU law - from what I found, only France has a law about this, and it seems to only apply to devices that ship with headphones (i.e. it would apply to the combination of a smartphone with bundled headphones, but not to an audio device sold without headphones). Which is fortunate, because otherwise, according to EN 50332-2, the limit for an audio device sold without headphones would be 150 mV, which would surely mean most devices sold on the French market would be illegal!
There seems to be sources saying otherwise though
https://www.google.com/search?q=EU+volume+limits+on+devices&oq=EU+volume+limits+on++devices
 
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If you look more closely at these sources, you will only see press releases, misleading news reports and various statements of intent or information. I failed to find any reference to any kind of actual EU law or regulation. As far as I can tell, out of all the EU member states, only France as an actual law and decree about sound level limits on consumer devices. The site I cited actually states "this is not a legal requirement in member states apart from France".

It is true that many companies will treat "legal requirement in France" as "legal requirement in the EU" in order to simplify their logistics. But as I previously said, even the French law doesn't seem to apply to devices that are sold without bundled headphones.
 
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If you look more closely at these sources, you will only see press releases, misleading news reports and various statements of intent or information. I failed to find any reference to any kind of actual EU law or regulation. As far as I can tell, out of all the EU member states, only France as an actual law and decree about sound level limits on consumer devices. The site I cited actually states "this is not a legal requirement in member states apart from France".

It is true that many companies will treat "legal requirement in France" as "legal requirement in the EU" in order to simplify their logistics. But as I previously said, even the French law doesn't seem to apply to devices that are sold without bundled headphones.
I have this system property on Asus Zenfone 3 phone(max output only 0.3V)

[use.audio.eu.parameters]: [true]

A call to Asus confirmed that it is due to EU regulations. The max output of iPhone is 1V. If any UK or European iPhones have a lower limit, you already have your answer.
 
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I received my USB 3.0 adapter today. I measured a maximum output of 0.5V out of windows with my Model A2155, I'm a bit disappointed, does it mean that the hardware is not the same as the model amirm measured ? Now let's say I listen with the volume at 90/100, will it distord more than the 1V model at 40/100 ?
 
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Perhaps it is Asio4All that somehow forced out more juice ?
I'm afraid it's not, i used Asio4All with Jriver and still got 0.5V. For those who wonder, even with the 0.5V output, this dongle still sounds subjectively better than my motherboard which uses Realtek AC887 with a pair of AKG K712PRO Headphones (sounds cleaner).
 
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I have this system property on Asus Zenfone 3 phone(max output only 0.3V)
[use.audio.eu.parameters]: [true]
A call to Asus confirmed that it is due to EU regulations.
Again, this is most likely due to Asus taking French law and applying it to the larger scope of the EU to avoid having to deal with subtle differences between EU countries. I highly doubt the people answering the phone at the Asus hotline are experts in EU regulations.

EU law is public on the Internet, so, if there is such a regulation, it should be easy to find it, but I was unable to. This leads me to suspect there is no such thing. (In contrast, it was quite easy to get to the French decree.)

While doing that research I dug a bit more into the French decree. That decree references the 60065 standard. I have obtained a copy of that standard and the relevant section is "Z1 Protection against excessive sound pressure from personal music players", which states:

[In] a personal music player provided with an analogue electrical output socket for a listening device, the electrical output shall be ≤ 150 mV measured as described in EN 50332-2, while playing the fixed “programme simulation noise” described in EN 50332-1.
EN 50332-2 states:

The player input signal shall be as specified in EN 50332-1:2013, Clause 5 recorded on the relevant medium with the specified level
All hardware and software processing systems, gain and tone control settings shall be set such as to reach the maximum sound level output.
The analogue audio output shall be loaded with a resistive load of 32 Ω per channel.
The maximum output voltage V m shall be defined as unweighted r.m.s. voltage at the load
EN 50332-1 states (emphasis mine):

The test signal used to determine the maximum sound pressure level of headphones shall be programme simulation noise, as defined in HD 483.1 S2. [...] This signal is a weighted stationary Gaussian noise and can be obtained from pink noise with a suitable filter network.
For digital listening devices, the test signal shall be applied to the listening device with an r.m.s. amplitude of - 10 dBFS, where 0 dBFS is defined as being the maximum RMS amplitude of a sinusoidal signal corresponding to the full scale of the digital interface.
Okay, so that means my other source was actually misleading, it's not 150 mV max output, it's 150 mVrms at -10 dBFS. So the actual maximum output that French law allows, at 0 dBFS, is actually… 474 mVrms. Which is more reasonable, and matches the max output of the A2155 model quite well. So yeah, the 0.5V max output for models sold around the EU might be ultimately be linked to this regulation, as wiggum suspected.

That said I still suspect that Apple is being overparanoid here, because the French decree clearly states that it only applies to "devices mainly consisting of a listening apparatus that can be worn inside, over, or around the ears" which seems to exclude devices that don't come bundled with headphones, such as this Apple adapter.
 

Veri

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I'm afraid it's not, i used Asio4All with Jriver and still got 0.5V. For those who wonder, even with the 0.5V output, this dongle still sounds subjectively better than my motherboard which uses Realtek AC887 with a pair of AKG K712PRO Headphones (sounds cleaner).
0.5V into AKG 712Pro does not sound like a satisfying experience to me :D !
 
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So you feel my pain and my disappointment, but it's still better than what I used before, for 10€ I can't complain, I never listen loud music.
I've had AKG K701 for a very long time and I never found them to sound too good powered by a portable device. IMHO trying to drive AKG 7XX cans from a portable device's output (or a dongle) to a satisfactory level + fidelity is a bit overly optimistic. If you won't hit the voltage limit you'll hit the current limit of a device trying to drive those hungry cans with a tiny output stage.
 
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Has anyone tested Sennheiser HD600 or 650s with these cables? :)
 
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Has anyone tested Sennheiser HD600 or 650s with these cables? :)
Yes, Amir tested it with 650, here is the text from the review:
"Switching to high-impedance 300 ohm Sennheiser HD-650 nearly killed performance. The sound was OK but bass is weak and dynamic range just not there. Here my reference is more powerful desktop and battery operated portables. "

I have also tried it with HD-650 on my PC and it lacks bass in comparison with my motherboards amplifier (Gigabyte AMP-UP).
 
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I "field tested" the apple dongle with my pixel 2 xl + sennheiser momentum 2 (18ohm) at the gym yesterday and the day before yesterday. At 100% volume it sounds plenty loud, it sounded louder, cleaner and more dynamic than what I'd get out of the google dongle at around 85%, beyond 85% google dongle + momentum 2 start to sound distorted/strained playing EDM. On the other hand people who listen to classical music a lot (not me) may not be satisfied using the apple dongle on an android device without root, because a lot of classical recordings would require additional gain to sound good.
 
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Yes, Amir tested it with 650, here is the text from the review:
"Switching to high-impedance 300 ohm Sennheiser HD-650 nearly killed performance. The sound was OK but bass is weak and dynamic range just not there. Here my reference is more powerful desktop and battery operated portables. "

I have also tried it with HD-650 on my PC and it lacks bass in comparison with my motherboards amplifier (Gigabyte AMP-UP).
I bought a USB C to USB A dongle to use the Apple DAC with my PC. Testing it with my Sennheiser HD518(3.2 mW/100dB SPL), it sounds great. I can boost the bass to deafening levels and doesn't feel weak at all. It is amazing what $10 buys. Apple could have easily priced it at $50.
 

Veri

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I bought a USB C to USB A dongle to use the Apple DAC with my PC. Testing it with my Sennheiser HD518(3.2 mW/100dB SPL), it sounds great. I can boost the bass to deafening levels and doesn't feel weak at all. It is amazing what $10 buys. Apple could have easily priced it at $50.
Now now don't give them any ideas.. :) I also think they purposely priced it at $10 while make it as flimsy as possible, making sure you're likely to buy more of them... I already lost one of these adapters just because they're so damn small lol
 
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As a long time user of iDevices i think i can clear up what happens with iDevices and iDongles output power. I don't own an Apple USB-c dongle but i do own the 3.5 dongle.

The Apple Lightning to 3.5mm dongle output power depends on the host. If the host is and European iPhone it delivers 0'5 Vrms. If the host is an iPad or a non EU iPhone the dongle belts out 1 Vrms.

This is due to the fact that Apple sticks (with the dongle as well) to CENELEC regulations that came in place on 2013-01-01 for portable devices.. By them, any portable device that sells with bundled earphones will output a user removable limit of 85dbs and a non removable limit of 100 dbs. Plus when volume exceeds of 85 db with bundled earphones visual cues will show (That's why EU iPhones HUD volume bar has colors from the 10th square onwards. Squares that are nowhere to be found on non EU iPhones and iPads -whether they are European or not-). Thus there are two volume limits on EU iPhones (85/100) and on Music menu you can disable the 85 one but not the 100 one. So...an EU iPhone will always output half the Vrms of an iPad or a non EU iPhone.

Since iPad does not sell with bundled earphones both its hpo or a Lightning dongle hooked to it deliver 1 Vrms

When the Apple Lightning to 3.5mm rolled out, as a lawyer, i hoped that its output would be 1 Vrms even when the host was an EU iPhone because it was not legally necessary (imho) to cap its output power but it seems to me that Apple played it safe to avoid eventual EU fines (even though a stand alone sold dongle should not be capped because (as iPads) it has not bundled earphones).

Apple EU iPhone output voltage cap is firmware enforced. If your iPhone has an EU serial number it will be capped.
 
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This is due to the fact that Apple sticks (with the dongle as well) to CENELEC regulations that came in place on 2013-01-01 for portable devices..
If you look at the top of this page (specifically this post and what it responds to) you'll see I've been discussing this particular point at great length. I agree that Apple is probably not legally obligated to limit the output of the adapter (since it's not bundled with headphones), and yes, they might have done it anyway out of oversight or legal paranoia.
 
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If you look at the top of this page (specifically this post and what it responds to) you'll see I've been discussing this particular point at great length. I agree that Apple is probably not legally obligated to limit the output of the adapter (since it's not bundled with headphones), and yes, they might have done it anyway out of oversight or legal paranoia.
Yep. I read it. This is a great thread.

(To me) the Apple Lightning to 3.5mm dongle it's the most impressive electrical engineering i've witnessed in quite a while.

With 0,3 ohms of Zout, pitch black background, very low distortion, very low crosstalk and ludicrous power consumption it drives balanced armature and low impedance earphones flawlessly. Better than many expensive boutique gear that i have tried.

Very low (and non-linear) impedance and very sensitive Shure SE535 and Shure SE846 smoke when driven by the dongle.

You can see accurate measurements of the 3.5 mm dongle on the sound science forum of headfi and on ohm-image.

I assume that USB-C dongle plugged to an idevice falls in the same ballpark.

Apple clearly sticks to more demanding audio standards than the rest of the smartphone competition with the glorious exception of LG (which would be more glorious if it allowed users to manually choose gain).
 
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