First let me say THANK YOU for keeping the headphone jack! Can’t tell you how frustrating it is being forced to use a dongle with any of my headphones when listening to music. Any chance us audiophiles will be getting a decent DAC in this phone? It’s obviously not a primary focus but MAN would it be nice…
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I’d also love to see some decent DAC. They shouldn’t be that expensive anymore. It doesn’t have to be the top-notch product (if that’s too expensive that is), but phones are used as portable music players.
So please include some goodish DAC 
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i believe we should have a poll thread to be able to ascertain what is the minimum specs most people have/need on their headphones. in-ear or over-ear types doesn’t matter.
i have a pair of new Pioneer in-ear headphones that go for 5hz-50hz at 26 ohms with a sensitivity of 108 db. flac types go well here not sure about mp3s (not high enough bitrate probably)
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ok since i came across this youtube video while i was researching dac/amp i thought you might be interested in hearing why there is actually less you need to be concerned about
in short - phones/smartphones are not suitable for hi res audio since that is ussually the job of an external AMP/DAC dedicated for 16/24/32bit amplitude proccessing and sufficient sample rate in this case 44khz at maximum(because the average human hearing can go up to 20 khz analog so double that for high fidelity digital reproduction acording to Niquist theorem explained in video)
At least 96 db SNR is required but can go higher with hardware dithering up to 120db.
between 120db-140db max possible is over the top and not neccessary because of how human hearing works also explained in the vide.
Making a smartphone with such great specs will be very difficult and expensive and will not compare to dedicated external amp/dac since components have to fit too tight together and there is noise and crosstalk.
best option is external AMP/DAC with 24bit at max 44khz native (can go higher with optional internal hardware oversampling if required). software oversampling degrades overall experience. so over 44khz is really only niche case scenario.
for audio production you need 24bit and only for listening to uncompressed source 16 bit is all you need.
so i have been researching for external libre DACs/AMPs and found this:
not sure if the firmware is 100% freed of binary blobs maybe someone with more experience can confirm this. they link to a store where you can find hardware and electrical diagrams in order to build your own.
if you know of other places to visit please post here.
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Thanks, that was very informative! For me, the big advantage of having a decent dac in the phone would be to have the best quality audio I could get without having to carry a second device with me. I’ve used portable external dac/amps, and my preferred source is my Cowon player, but if I only want to bring one device with me a decent dac in the phone seems the way to go…wouldn’t need a really powerful amp either since I’m mostly using iem’s when I’m out and about, and the other cans I’m using with it are pretty low impedance.
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@Photojoe4
it depends what kind of IEM’s (in-ear monitors) you are using. some very high end expensive hi-fidelity ones absolutely benefit from good external AMPs. there are some external DACs who also include AMP circuitry there is no need for two separate ones only on the big/heavy/large ones used for very high powered speakers.
if you just want some small/high end amp/dac for smartphone you can have a look here:
https://www.headphone.com/blogs/news/top-3-usb-headphone-amp-dacs-under-200-in-2018
they probably have binary blobs in their firmware seeing as they are so expensive. 24-32 bit is really overkill unless you record music.
I had the black dragonfly, I also had a Fiio Q1 that I liked. That’s what led me to get my Cowon. But if I’m going to bring a second device with me for audio, I’d just use my Cowon (I’ve got custom EQ settings for all of my headphones, and that would save the battery on the phone as well).
just a quick bump and update for interested people.
turns out dedicated hifi audio usb cables really make a big difference regarding sound quality not data.
noise plays a big part in sound quality. that is a fact with pcs and usb.
No, that guy in the video is completely out of reality. Did you even look at the top comments in the comment section?
A digital signal is either received or the sound will skip significantly, either the data is there or it is not. There is no “noise” since the signal is either on or off.
The guy in the video uses a DAC powered over USB and his cheap USB cable is likely rated for less power output than the DAC requires so the DAC cannot function properly. That has nothing to do with the digital signal. He likely only needs a $2 USB cable rather than a $1 USB cable. Anything past that is wasting your money.
Please stop spreading FUD.
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I watch the video also and i’m still not 100% sure. I like to believe the guy really had a better experience with the cables, but i doubt that buying the cables is the right solution or the core of the problem.
With my understanding this all came from the common ground needed as a reference point for data dtrancmission. So the ground of the pc is connected to the DAC. Doesn’t matter if there is extra power supply for the DAC or not. So it is possible to transmit noise from the pc to the DAC. And i also believe pcs and usb grounds are noisy. But i don’t see the big problem in damping this noise in the DAC. So i’m more likely to say if one needs such cabels to get good sound out of the DAC, it faild hard on the damping and isn’t worth its money. One can fix this with overly expensive cables but that is just a bad and expencive fix for a bad product.
Disclaimer: I don’t have any deeper electrical engineering experience. So please correct me if i am wrong. I am interested in the right explanation.
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I fully agree with @johan-bjareholt. Either the guy is doing it on purpose, or is affected by the placebo effect. It starts with guy in the video always mentioning how these cables are better for transmitting audio, but not making a difference for data. Surprise: Until the DAC converts the binary data it receives over USB, there is no analogue-audio just bits. So much for “filtering/denoising” the data lines.
For the power pins on USB (given that the DAC is supplied only via USB): While I can imagine that in theory having an extremely noisy (and at that level I wouldn’t even call it noise anymore) power source could eventually degrade your audio signal, I’m confident basically any DAC implements circuits to completely flatten/counteract this by default. So again this is nothing to worry about either.
Also for the non-digital part of audio-transmission: there’s the story online about “monster cables vs. coat-hanger”. Spoiler: Don’t buy overpriced audio cables.
One last thing: Toslink cables with gold-plated connectors don’t improve sound-quality either.
At least the video gave me a good chuckle 
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Haha what, is that seriously a thing? That’s hilarious
Nice rip of.
You have my full backup that there are many not worth buying cables on the market. One idea that came to me why his set might be stat noisy is his all-in-one sony pc. I think LCD backlight can get quiet noisy as the are often dimmed via PWM while drawing a considerable amount of energy. Only good prof for me would be a oscilloscope showing the nois on the ground with then testing DAC on noisy Power and no noisy power. And maybe if there are many bad DAC how much these cables can do. But i never would spend that much on usb cable either. If the DAC doesn’t work with the included normal cable i would return it.
i got a phone recently that delivers audio via usb-c and was disappointed in the first place as well. later i found it much nicer to connect only one plug in my car (i use the mobile for all, audio, charging, navigation, … ) with a y-dongle and the dongle for the headphone is quite small. there are even headphones with usb-c out there, no dongle at all… so jack or not: both has its benefits.
Well, having a jack does not prevent that. It just gives you options.
i’m just a fan of simplicity, i thing that’s not there can’t break, doesnt consume space, does allow dust to enter 
But you would be able to do that with a phone which has both usb-c and a headphone jack aswell, so there’s not really any pros with only having usb-c-
guys i’m not an audio/electrical engineer either but i think you missed the point about expensive dedicated usb cables vs non-dedicated common(even quality) ones.
the problem is that common non-dedicated audio usb cables don’t have good separation/insulation between the audio wires that carry the 0s and 1s and the power lines. thus noise affects the power in the dac. sure most quality DACs feature noise filtration tehnology for the ground but that doesn’t mean that output analog noise isn’t affected at all.
the point is that we want to get as close as possible (playback) to original sound recording by any means neccesary. That means that all components in the in-out chain play a part in this. Yes it is expensive and you probably won’t get any added value if you’re not an audio-phile.
Why would you go to the opera when you can listen at home ? why would you want to experience clean sound-separation and audio-fidelity when all you are interested in is the information ?
if listening to music was only about the message and the information we would all be listening to Rap and Hip-Hop on cheap equipment. no offense to anyone here !
sure there is a good amount of Snake Oil involved when selling expensive products but can you really say no to a blind test ?
Me nether, but I have enough knowledge to undestand what is happening at least. The thing you are missing is that interference on a digital audio signal might make that 0 into a 0.01 which is still interpreted as a 0. Unless you put your digital cable right beside a 10kW transformer that signal will not get anywhere close to 0.5 even with a unshielded cable.
Also if you wonder why digital cables such as ethernet cables are shielded it’s because they need to transfer the digital signals at such high frequencies that the 0’s and 1’s barely has time to switch until they need to switch again so they are much more exposed than slow USB cables.
If you are wondering why your internet pages are not distorted because the data over your unshielded ethernet cable/wifi was distorted it’s because they have checksums which mathematically verifies that what they received is what was actually sent instead of possibly garbage because of interference. If you actually do get a garbage packet over ethernet/wifi and browse the web, your computer will request the package again from the sender until it gets a verified non-distorted package.
The same thing goes for audio over USB, if the digital signal is distorted the receiver will find that out since it is verified via a checksum and requests the sender to send the audio again.
If you put your unshielded usb cable right next to a power plant you will still get the exact same quality as you get at home, but it might be too slow to play in real time because 99% of the packages are distorted and needs to be sent again.
Because microphones and headphones cannot perfectly capture and recreate the atmosphere and sound (even though they do recreate it incredibly great nowadays).
The digital signal is fine, lossless formats are mathematically lossless. Music which is made only with a computer and no microphones can be transferred mathematically perfectly, but our ears are still not digital so we need to convert it to a analog signal in the end anyway so we can’t hear it in the perfect format.
@johan-bjareholt your explanation is technically (mostly) correct, but misses what reC claimed.
I’d just add that USB cables nowadays work in the similar speed levels as network cables. Usually they don’t need shielding because they are much shorter, and possibly also use the twisted pair “trick”.
What’s more, the data line is kinda self-neutralizing, meaning within a very short time (every few cycles) the same amount of 1’s and 0’s are transmitted, esentially resembling a constant 0.5.
@reC is not saying the noise is bad to the digital data, but the digital data is bad for the DC, making it unstable. What you have to realize though, is that a USB 2 device has a clock-speed of 480MHz, while your DAC has 48kHz. So, during the time the DAC converts ONE sample, the data line transported 10,000 bits, guaranteed to be 0.5 on average, and never more than 5 consecutive 0s or 1s. The impact on the DAC will be homeopathic. You can not stress enough how much higher the influence of the power source is: The DC that you receive from the PC (USB port) is already a mess, or at least you really have to expect it. The CPU might adapt it’s core voltage several thousand times a second. THIS has an impact on what DC external devices see. And for this reason, a good DAC has to be able to cope with unstabilized DC (which is possible), but a shielded or gold-plated cable will not help the slightest.
The definition of snake-oil is “no useful, scientifically proven effect at all”, not “I don’t need that extra quality, I’m already satisfied with the standard”.
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