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Review: Apple vs Google USB-C Headphone Adapters

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I have used these and the ones that came with one of my dongles: https://smile.amazon.com/gp/product/B07B47V967/ref=oh_aui_search_asin_title?ie=UTF8&psc=1

They both work. And no, I did not have to change anything in Windows other than setting the levels in the control panel.
I was amazed by the sound quality and power of Apple USB-C to Headphone Jack - just wow, I really can't go above 40%...
And to think that I was thinking to buy something that costs 7-8 times of the price of this dongle.

The only thing is how long it will last because the build quality feels bad...
 
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Hey, does anyone know if there's been some sort of silent update to apple's usb c to aux adapter?

I bought one when they first started getting sold in stores, and found that it was quiet as hell playing off my pixel. Eventually I lost that one so I went and got another which get to a decent volume off my pixel at ~40%. At first I thought there was a driver update of some sort, but then I found the original, and it seems like they might have silently release a new version of the dongle

Got both in store at best buy, so I know they're both real
 

yue

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The measurements are continuous. Bass in music is impulsive. So it is possible to get music to play loud at mid-frequencies and when the bass comes, it depletes the power supply caps resulting in distortion.
This is a very interesting theory!

Are there any technical evidence that continuous vs impulsive might be different? no matter how sudden the impulse is (let's say it reaches from 0 to full volume in 0.001s), the slew is like to a 1Khz wave in full amplitude, so it is much, much slower than the high-frequency sound (say 20KHz), and fa more slower than the slew rate of a typical op-amp (a few volts per micro-second).

Anyone with a electrical engineering degree can explain whether or not an impulse may be difficult to produce with a low power, if such power can drive a continuous wave at full amplitude with great accuracy?


I am thinking about how to test for this in measurements.
How about produce a music with intermittent sine wave at low frequencies and full amplitude + silence, and see if it can reproduce the beginning of the sine wave precisely?
 
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Hey, does anyone know if there's been some sort of silent update to apple's usb c to aux adapter?

I bought one when they first started getting sold in stores, and found that it was quiet as hell playing off my pixel. Eventually I lost that one so I went and got another which get to a decent volume off my pixel at ~40%. At first I thought there was a driver update of some sort, but then I found the original, and it seems like they might have silently release a new version of the dongle

Got both in store at best buy, so I know they're both real
Dunno, the one I got works amazingly with my PC but when I plug it to my Xiaomi Mi 8 it is really quiet even at max volume.
 

bravomail

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ex-Microsoft guy having to recommend an Apple product
There was a generation of consoles (PS3, Xbox 360) and at the same time Apple moved to Intel.
The quote from those times was: "You know you live in a crazy time, when Microsoft console runs on Apple (IBM/Motorola PowerPC) processor, and Apple runs on Intel processor"
:)
Now back to normal.
PowerPC dead. Motorola CPU dept is dead. Intel won.
 
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I've been using a Pixel 2 XL + sennheiser momentum 2 with the stock 3.5mm dongle since the phone hit the market a year+ ago. Last week the 3.5mm dongle stopped working, so I ordered another copy from the Google store. To my surprise when comparing the new dongle (v2) against another copy of v1 google dongle I could hear a difference in volume and quality. After finding this thread I also ordered the apple usb 3.5mm dongle to see if I may get lucky using one of those instead, supposed to get delivered tomorrow. It's a shame that Google actually replaced v1 dongles with a lesser v2 product, it especially affects people who like using full size cans with their phone because max output becomes even more limited with v2.
 

amirm

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I've been using a Pixel 2 XL + sennheiser momentum 2 with the stock 3.5mm dongle since the phone hit the market a year+ ago. Last week the 3.5mm dongle stopped working, so I ordered another copy from the Google store. To my surprise when comparing the new dongle (v2) against another copy of v1 google dongle I could hear a difference in volume and quality. After finding this thread I also ordered the apple usb 3.5mm dongle to see if I may get lucky using one of those instead, supposed to get delivered tomorrow. It's a shame that Google actually replaced v1 dongles with a lesser v2 product, it especially affects people who like using full size cans with their phone because max output becomes even more limited with v2.
Yes, it is a shame they went backward. Let us know if the Apple dongle works for you because it did not with my Samsung S8+.
 

edechamps

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I just received the Apple USB-C dongle that I ordered on the UK Apple Store.

I did a few informal measurements on it, just to make sure I didn't get a weird variant. My results generally agree with amirm's. I measured an amazing 0.5 Ω output impedance, yay!

Hey, does anyone know if there's been some sort of silent update to apple's usb c to aux adapter? I bought one when they first started getting sold in stores, and found that it was quiet as hell playing off my pixel. Eventually I lost that one so I went and got another which get to a decent volume off my pixel at ~40%. At first I thought there was a driver update of some sort, but then I found the original, and it seems like they might have silently release a new version of the dongle
Sadly, the one I just bought (ordered 2019-02-18 on online Apple Store UK) still suffers from this gain issue with Android phones. I measured a paltry -26 dBV (0.05 Vrms) max output with my Pixel 3, which is way too low to be usable with anything other than very sensitive IEMs.

When using the dongle with Windows, it's the same output level initially, but that's because the default gain is -20 dB. In Windows you can adjust the gain, and get it up to -6 dBV (0.5 Vrms) max output, which is more reasonable. Sadly, in Android it looks like it's stuck at its default gain of -20 dB with no way to adjust it. That really sucks, that dongle would have been perfect for Android devices otherwise.

(By the way, the maximum output level I could measure when using the dongle with Windows was 0.5 Vrms, but amirm measured 1.0 Vrms. Not sure why I'm getting a different number there.)
 
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I just received the Apple USB-C dongle that I ordered on the UK Apple Store.


When using the dongle with Windows, it's the same output level initially, but that's because the default gain is -20 dB. In Windows you can adjust the gain, and get it up to -6 dBV (0.5 Vrms) max output, which is more reasonable. Sadly, in Android it looks like it's stuck at its default gain of -20 dB with no way to adjust it. That really sucks, that dongle would have been perfect for Android devices otherwise.

(By the way, the maximum output level I could measure when using the dongle with Windows was 0.5 Vrms, but amirm measured 1.0 Vrms. Not sure why I'm getting a different number there.)
If your Android phone is rooted, you could edit mixer_paths.xml file to set the digital gain. Unrooted, there isn't much we can do.
 
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I received the apple usb dongle (ordered from Apple store in the US, shipped from Los Angeles). I didn't take measurements but I can roughly say that the apple dongle at 100% volume sounds as loud as google v1 dongle at 80% (where I'd usually set it), which makes it quite usable with my sennheiser momentum 2 headphones. I'm guessing it's currently limited to 0.5v output and I'd need to root my pixel2xl to adjust the gain further. Subjectively the apple dongle also sounds better.
 

edechamps

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I bought one when they first started getting sold in stores, and found that it was quiet as hell playing off my pixel. Eventually I lost that one so I went and got another which get to a decent volume off my pixel at ~40%. At first I thought there was a driver update of some sort, but then I found the original, and it seems like they might have silently release a new version of the dongle
Sadly, the one I just bought (ordered 2019-02-18 on online Apple Store UK) still suffers from this gain issue with Android phones. I measured a paltry -26 dBV (0.05 Vrms) max output with my Pixel 3, which is way too low to be usable with anything other than very sensitive IEMs.
(By the way, the maximum output level I could measure when using the dongle with Windows was 0.5 Vrms, but amirm measured 1.0 Vrms. Not sure why I'm getting a different number there.)
I received the apple usb dongle (ordered from Apple store in the US, shipped from Los Angeles). I didn't take measurements but I can roughly say that the apple dongle at 100% volume sounds as loud as google v1 dongle at 80% (where I'd usually set it)
We might get some more insight if we compared the product details of our respective dongles. My dongle (0.5 Vrms max output from Windows, stuck at -20 dB gain in Android) has this sticker:

IMG_20190223_170157(1).jpg


In particular it would be interesting to know if your dongles bear the same "MU7E2ZM/A" and "Model A2155" references.
 

DDF

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A little environmental test note for the Apple dongle. Living in Ottawa, you deal with what Mother Nature gives. I often take evening walks for 1-2 hours and the dongle lasted 30 minutes at -20C (outside jacket pocket) before refusing to synch with the phone. The phone (i7) would continue on speaker for at least another 30 minutes before giving up the ghost from the cold.

Not surprisingly, there's also a serious incompatibility issue between the apple adapter and my Bose Android QC-20 NC headphones: audio clicks repeatedly. Found a workaround: turn off QC20 NC, plug in only half way till click stops (a few seconds), then insert all the way and turn on NC.
 
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We might get some more insight if we compared the product details of our respective dongles. My dongle (0.5 Vrms max output from Windows, stuck at -20 dB gain in Android) has this sticker:

In particular it would be interesting to know if your dongles bear the same "MU7E2ZM/A" and "Model A2155" references.
Here's what mine looks like

 
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edechamps

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The apple usb-c to 3.5mm jack adapter was also measured in xda forum and the output voltage on windows is 0.5V : Link to xda thread
Yes, that is consistent with my own results.

I have a MU7E2ZM/A Model A2155 usb-c adapter
That's the same as mine. You should get similar results as I did (0.5 Vrms from Windows, 0.05 Vrms from Android, 0.5 Ω output impedance).

without your specialized tools can i measure the output voltage
Yes, that can be done with a simple AC voltmeter. Generate a 60 Hz full scale sine wave using any tool you like (Audacity, REW, SoX, etc.). Play it through the adapter and probe the output voltage of the jack using the voltmeter (protip: a jack to RCA adapter will make this easier). The voltmeter display is in Vrms. If you do that from a Windows machine at full volume, it should read 0.5 volts. From Android at full volume, it will read 0.05 volts.

Are you using USB 3.0 adapters ?
Yes, but what type of adapter you use doesn't matter, it's purely a wiring thing.
 
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Yes, that can be done with a simple AC voltmeter. Generate a 60 Hz full scale sine wave using any tool you like (Audacity, REW, SoX, etc.). Play it through the adapter and probe the output voltage of the jack using the voltmeter (protip: a jack to RCA adapter will make this easier). The voltmeter display is in Vrms. If you do that from a Windows machine at full volume, it should read 0.5 volts. From Android at full volume, it will read 0.05 volts.
Well, for a noob like me that was a lot of fun, i measured 52mv out of my galaxy S8 (I should receive USB adapter tomorrow so I'll test out of windows), and a resistance of 0.9ohms.
Now I understand that we can root our phones and change the gain setting, but how can we reach 1V out of windows 10 ?
 

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edechamps

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a resistance of 0.9ohms.
How did you measure that? If you used the ohmmeter on your multimeter that's not a valid measurement - the voltmeter will only measure the resistance at DC, which is not necessarily the same as the impedance at audio frequencies.

If you want to do an output impedance measurement you need to load the output with a resistor of known value R (e.g. 16 Ω) and measure the output voltage again while the output is loaded. The output impedance is R * ((unloaded voltage/loaded voltage) - 1).

Now I understand that we can root our phones and change the gain setting, but how can we reach 1V out of windows 10 ?
I was not able to reach 1V with this particular model, only 0.5 V. I suspect those who measured 1V (such as amirm) have a different model.
 
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How did you measure that? If you used the ohmmeter on your multimeter that's not a valid measurement - the voltmeter will only measure the resistance at DC, which is not necessarily the same as the impedance at audio frequencies.

If you want to do an output impedance measurement you need to load the output with a resistor of known value R (e.g. 16 Ω) and measure the output voltage again while the output is loaded. The output impedance is R * ((unloaded voltage/loaded voltage) - 1).



I was not able to reach 1V with this particular model, only 0.5 V. I suspect those who measured 1V (such as amirm) have a different model.
As a real noob, i did use the ohmmeter setting on my multimer, thank you for your help. OK we will have to wait amirm answer to see if he has another model.
 
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We might get some more insight if we compared the product details of our respective dongles. My dongle (0.5 Vrms max output from Windows, stuck at -20 dB gain in Android) has this sticker:

View attachment 22433

In particular it would be interesting to know if your dongles bear the same "MU7E2ZM/A" and "Model A2155" references.
Sadly, I chucked the packaging for both of mine weeks ago, so I can't verify the numbers on the packaging. However, a close up look on the cable of both mention Model A2049
IMGP0631.jpg

The one with the yellow dot on it is the original one I got. Tried them both again to double check and I found the reason for the difference in volume, apparently one of them was using android's driver while the other seems to have been accidentally fat fingered into use neutron's driver(and it seems like that got broken in a recent update so trying to use that now only results in a loud annoying buzzing, dang:confused:... why the heck doesn't the google store have a rollback feature again?)
 
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I was not able to reach 1V with this particular model, only 0.5 V. I suspect those who measured 1V (such as amirm) have a different model.
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.
Can't wait any longer for Brexit, don't you?:p
 
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