Lightning to 3.5 mm headphone "adapter"

[Joe McG]

I'm an electrical engineer and I have had some serious doubts about the functionality and audio quality of the lightning to 3.5 mm headphone adapter. This is because Apple has stated that the lightning port is "all digital" so the digital audio stream must be converted to analog for the 3.5 mm audio jack.

That being said, there must be a tiny DAC inside the lightning to 3.5 mm adapter. However, it is so small that it would be an incredible engineering feat to fit any decent DAC inside this connector.

I received my iPhone 7 Plus yesterday and my fears were realized. The adapter works just fine but the audio quality is absolutely awful. Apple must be using a ridiculously cheap, low quality DAC in this cable. It's really disappointing that they would market this as an "adapter" when it really is a DAC and DACs aren't trivial. The DAC is EVERYTHING when it comes to music quality. I guess many people won't notice the low audio quality and it seems Apple is banking on this.

On top of that, Apple doesn't support the Bluetooth aptX codec, only AAC and it has been really difficult to find Bluetooth headphones that support high quality AAC. I did find the Klipsch S6 Bluetooth headphones and have ordered a pair to test. Standard Bluetooth headphones use the SBC codec and this has mixed results.

I hope that eventually there are 3rd party lightning DACs that become available in the next few months which are of higher quality.

It's also disappointing that most of the tech blogs out there don't seem to have an engineering expertise to point these sorts of potential issues before they become the next "Apple-gate". This was an obvious potential issue to me from the start.

 

[pantlesspenguin]

My hope is that audio companies will start manufacturing lightning connected ear buds. However, I might still be left in the dark because only the ones that lay flat in my ears will stay put during excercise. I've hoarded a lot of these types of ear buds since they're becoming more rare, so it's disappointing to hear that the converter isn't all that great. I was just going to slap that on the backup pair I always keep in my gym bag and use the lightning connected ones that come with the phone until manufacturers start making lightning connected ones that fit in my ears.

 

[metllicamilitia]

I never expected anything quality with audio from Apple. The only reason the classic iPods were popular for audiophiles was because it could be Rockboxed. So unfortunately this is no surprise for me.

For those that have no issue with EarPods, you will likely not notice anything wrong with the DAC Apple used in the adapter. Once you understand how bad EarPods are, then you'd understand how bad the DAC is, and would almost never listen to music on your iPhone again. Again, for the majority, this is not an issue.

 

[Joe McG]

I never expected anything quality with audio from Apple. The only reason the classic iPods were popular for audiophiles was because it could be Rockboxed. So unfortunately this is no surprise for me.

For those that have no issue with EarPods, you will likely not notice anything wrong with the DAC Apple used in the adapter. Once you understand how bad EarPods are, then you'd understand how bad the DAC is, and would almost never listen to music on your iPhone again. Again, for the majority, this is not an issue.

I don't really consider myself an audiophile so I think the quality of audio coming from the standard jack up to iPhone 6s was pretty decent. The adapter is a step back IMO. You can really hear it with lower frequencies. It reminds me of crappy Bluetooth headphones, which apparently Apple is trying to convince everyone is better than wired headphones.

 

[tai4de2]

On previous models that did have a 3.5mm jack, the DAC was on the phone mainboard and was similarly space-constrained. I think the DAC in the adapter cable isn't necessarily smaller than the ones in older iPhones. Of course Apple still might have used a DAC of poorer quality in the adapter...

Did you have an iPhone before you got the 7? I'd be curious about the results of a head to head comparison with the same headphones.

 

[tekjunkie28]

The lightning port just passes analog audio to the 'adaptor' which just is a conversion cable to 3.5 mm headphone jack. The iPhone 7 has 3 audio amps in it which I'm pretty sure is for the lightning earbuds. There is NO way a DAC fits into the lightning adaptor that I know of. I have you the ports digital audio function for years via USB cable to car stereo. Also I am an audiophile and the iPhone has always been nice to listen to but nothing can compete with SACD or vinyl. Can someone please confirm if I am correct about that 3rd audio amp in the iphone 7

 

[Joe McG]

The adapter is a DAC. Confirmed.

https://9to5mac.com/2016/09/20/apple-3-5mm-to-lighting-adapter-teardown/amp/

It's a low quality DAC which IMO produces muddy mids and lows, pretty typical of low audio quality.

 

[zog1977]

not a big deal in my opinion, people always need something to complain about

 

[Mdbills484]

yeah, unless you like decent quality audio with decent quality headphones.

 

[Joe McG]

I've given the adapter another chance and I've tested the EarPods with lightning connector since my last post.

I'm using the adapter with Sennheiser headphones and the mids just seem muddy. It's not the worst but it's noticeable on some songs with heavy guitar distortion.

The EarPods are actually pretty decent and on par with the previous EarPods. Perhaps they are doing some passive signal shaping on the EarPods to overcome the DAC limitations or maybe it's a different DAC. Not sure.

In any case, I'm hoping that some 3rd party companies come out with a better DAC which is also someone portable and suitable for workouts in the gym. DACs tend to be bulky and not very portable.

 

[chrgnthru]

I've been tweeting some of the headphone "HiFi" companies like RHA, Sennheiser, etc and RHA tweeted back to keep a eye out for new products in the next month or so. Sennheiser simply mentioned new upcoming head/earphones with different cabling options. Hopefully it's only a matter of time before someone releases a proper adapter.