Review: Apple vs Google USB-C Headphone Adapters

[smcc]

Hi, so when I was testing the Apple USB-C Dongle I noticed some issues using Audiotools as source for a 1kHz sine wave. (3dB sinad difference, so worth knowing).

Have screenshots, so think I should make a separate thread, probably/maybe applies to other DACs on iOS...which forum should I post this in?

Edit, in case I don't get around to it, use the generator in the FFT module, not the dedicated generator module...like so:

 

[smcc]

If anyone is wondering the Apple EU Lightning Dongle (0.9v) measures as good as the USB-C variant... L/R 97/98 Sinad...on iPhone 16 pro max via usb-c to lightning dongle.

Edit, 32 tones is way better.

 

[smcc]

Actually the Lightning one above is slightly cleaner, even at the same mV. EU USB-C variant here:

 

[smcc]

I added 32 tones to the last two posts...I used iPad Pro for both of those images (playing a file generated in REW)...some difference in the dongles!

I thought I had made a mistake, the difference is so big...so I redid it a few times...even at different dBFS...but no, it seems to be the case the Lightning Dongle is superior in that test.

 

[amanieux]

Correct . Only certain apple devices can unlock the EU version to 1V. Don't believe possible on android .

pluging the eu version in a european pc or tablet will give you 1V as the european law to limit loudness only apply to "mobile devices" (phones, daps etc...) weird that a laptop or tablet are not considered as mobile devices

 

[Jimbob54]

pluging the eu version in a european pc or tablet will give you 1V as the european law to limit loudness only apply to "mobile devices" (phones, daps etc...) weird that a laptop or tablet are not considered as mobile devices

I knew about laptops. I think Static had referred to some iOS devices being able to circumvent the 0.5v limit- hadnt realised it was a tablet / phone split. Do we know if android tablets can too ? I can try listening on my pixel tablet vs pixel phone and see if the extra 6db is obvious.

 

[staticV3]

I knew about laptops. I think Static had referred to some iOS devices being able to circumvent the 0.5v limit- hadnt realised it was a tablet / phone split. Do we know if android tablets can too ? I can try listening on my pixel tablet vs pixel phone and see if the extra 6db is obvious.

I have not found such a split on Android. Both phones and tablets appear to be capable of 0dBFS output to USB DACs out of the box, with one caveat being that certain ROMs leave 1-2dB of digital headroom (for mixing related IS-overs, I assume).

In the first place, is it actually confirmed that iPhones cannot bypass the EU dongle's 0.5V limit?

Sadly I don't have access to a USB-C iPhone, so was only able to test my A2155 and A2049 on a Mac and iPad.

 

[ZolaIII]

I knew about laptops. I think Static had referred to some iOS devices being able to circumvent the 0.5v limit- hadnt realised it was a tablet / phone split. Do we know if android tablets can too ? I can try listening on my pixel tablet vs pixel phone and see if the extra 6db is obvious.

Then it's regulated with OTG V output capability (200 mA but it can be enabled to do 500~550 as standard USB 2.0). To test that you will need root access and obviously to enable max OTG power delivery output.
Edit: irony is that those drive much less power than average USB dongle.

 

[DSJR]

It's probably because my Windows laptop is so old, but using a USB male - USB-C female adaptor, the EU Apple dongle has substantially less output than the US version and I cannot alter it. Same when I tried them from a 2m USB A - USB C female cable into my second sound rig, the US version being just about okay with volume control 75% up (it's one of these annoying 'HiFi' mid-way log laws which deafen you a third-way up on the control with a conventional 2V CD player input).

The SU1 dac now resides downstairs being fed from the CCA optical output and the second rig and long USB C cable now has a dinky DS2 on the end of it ('sounds' the same to me as the SU1 and has plenty of output ).

 

[staticV3]

Then it's regulated with OTG V output capability (200 mV but it can be enabled to do 500~550 as standard USB 2.0). To test that you will need root access and obviously to enable max OTG power delivery output.
Edit: irony is that those drive much less power than average USB dongle.

Are you referring to OTG current output capability, so 500-550mA for USB 2.0?

If so, then that's definitely not how any mobile device manufacturer limits headphone output voltage.
After all, we have dongles outputting 2V while drawing just 25-45 mA.

EU limits are AFAIK always implemented in the digital domain, either with artificial limits built into the operating system (e.g. Sony DAPs), or built into the headphone adapter (e.g. A2155).

Apple can unlock the A2155's EU limit using proprietary USB commands.

 

[ZolaIII]

Are you referring to OTG current output capability, so 500-550mA for USB 2.0?

If so, then that's definitely not how any mobile device manufacturer limits headphone output voltage.
After all, we have dongles outputting 2V while drawing just 25-45 mA.

EU limits are AFAIK always implemented in the digital domain, either with artificial limits built into the operating system (e.g. Sony DAPs), or built into the headphone adapter (e.g. A2155).

Apple can unlock the A2155's EU limit using proprietary USB commands.

If you read before and after then the context is what I said. If you don't I can't help you there. If you ask Apple you shouldn't be using it with Android in the first place. EU limits are less than what Apple did as shown on many phones while they had analog output. If you continue to imagine things then it's how you say it is. There is no debug bridge or proprietary command.

 

[donjoe0]

Which pics can I read the color/frequency response of the Apple type C dac dongle itself? Because I see that the dac is boosted in the treble region.

MEASUREMENTS: Apple's Lightning to 3.5mm Headphone Adaptor [MMX62] (CES 2018 Creative Super X-Fi audio, and A/C cable "proof"?)

A blog for audiophiles about more objective topics. Measurements of audio gear. Reasonable, realistic, no snakeoil assessment of sound, and equipment.

archimago.blogspot.com

iPhone 7 nachgemessen: Audio-Adapter liefert schlechteren Sound

Die wegrationalisierte Buchse des iPhone 7 erhitzt derzeit die Gemüter. Ausbaden soll es ein kurzer Lightning-Adapter. Doch statt den Sound zu verbessern, verschlechtert sich die Signalqualität, wie unsere Messungen zeigen.

www.heise.de

It should be reasonably flat all the way to 20 kHz (+/-0.12 dB) IF you feed it 44.1k or 48k material. You go up to 96k and it starts to make a mess of the FR, rolling off fast in the audio band, already down 0.5 dB around 15k. So upsampling in software not recommended. In fact if you have hi-res albums at 24/96 or higher, you should make sure they get downsampled first, or the fidelity goes bye-bye if all you're going to listen through is the Apple dongle.

Hell, even at 48k if we look at smcc's recent multitone plot for the EU USB version it shows big and easily audible in-band ripples that seem to fit some of what you were reporting from listening impressions, i.e. weakness around 6-8k. Same plot also fits the finding of 1dB weaker bass around 300-400 Hz vs. another modern (higher-powered) dongle in amanieux's thread where they thought they were going to "debunk a myth" with measurements and only educated themselves on the myth not being a myth at all.

 

[dreamscene]

Hey guys, I wanted to purchase the USB-C Apple Headphone Dac / Amp dongle with a USB A adapter for an older Windows PC. Will it affect it's performance with the USB A adapter? Has anyone done the test with a USB A adapter and found no issues eg. lower power to headphones etc?

My headphone is a Philips X2HR and I read before buying it that it's a very efficient headphone so a cheap USB Dac / Amp dongles won't have issues powering it to fuller volumes.

I was thinking to use this Ugreen adapter: https://www.amazon.com/UGREEN-Adapt...x=ugreen+usb+c+to+usb+a+adapte,aps,280&sr=8-3

 

[staticV3]

Will it affect it's performance with the USB A adapter?

It will not.

On my PC, I use this cable as strain relief and to have the dongle at a more convenient position. Power is unaffected.

 

[dreamscene]

It will not.

On my PC, I use this cable as strain relief and to have the dongle at a more convenient position. Power is unaffected.

Thanks mate for the quick reply.

 

[smcc]

So I just picked up a US USB-C Dongle (A2049) and indeed you get 1.026v with an EU iPhone (16 Pro Max in this case).

Also, I wonder if the limitation on the USB-C dongles is determined by the phone, and not the dongle. Has anyone tested a US dongle on an EU phone and actually measured 1v?

 

[dreamscene]

So I just picked up a US USB-C Dongle (A2049) and indeed you get 1.026v with an EU iPhone (16 Pro Max in this case).

Yea, this $10 Apple dac / amp dongle has blown me away. It pretty much rivals my Topping DX3 Pro+ Dac / Amp setup. Also runs my Sennheiser 50 - 150 ohm headphones without sweating. What is this sorcery?

 

[smcc]

Yea, this $10 Apple dac / amp dongle has blown me away. It pretty much rivals my Topping DX3 Pro+ Dac / Amp setup. Also runs my Sennheiser 50 - 150 ohm headphones without sweating. What is this sorcery?

dunno if I'd go that far...depends on what headphones of course..definitely the US one is worth sourcing, the EU one is unusable with HD560s for example...

 

[staticV3]

the EU one is unusable with HD560s for example...

The EU one will drive the 560S to 100dB SPL Peak.

Personally, I'd have to reduce the EU dongle to about 25% volume for comfortable loudness, so still tons of headroom for EQ and high CF recordings.

 

[dreamscene]

dunno if I'd go that far...depends on what headphones of course..definitely the US one is worth sourcing, the EU one is unusable with HD560s for example...

Yea, the A2049 model. It gets loud enough where there is no difference between the $10 Apple dongle vs my $200 Topping DX3 Pro+ desktop setup. I have the Philips X2HR and Sennheiser HD598, HD560s and Hifiman Edition XS. Only the Edition XS seems to sound more muted. It has flipped my understanding of audio requirements from now on. If you can't hear any detriment to the sound, what is the point of spending more than $10 on a dac / amp for most consumers especially when they match it with an efficient and sub 150ohm headphone. Bloody tiny dongle is the biggest secret in the audio world at the moment. It's a damn miracle what the Apple dongle can do.