Which DAC is being used?

[Jeff_hires]

Hi,
I've got a Kenwood Excelon DMX907S head unit in my car. I'm trying to understand what DAC is being used if I'm playing music from my android phone via usb cable and android auto to the HU. I'm thinking of upgrading my phone, so do I need to look for a phone with a good DAC? Or does my Head Unit's DAC always take precedence over the phone's dac? If the latter, how does the phone / phone app (Tidal) know to not process the audio using the phone's DAC, but rather "pass it" to the Head Unit DAC? Don't know if any intelligent "passing" goes on there or not. I'm showing my ignorance.
Thanks for any explanations to this audio processing path.

Click to read more...

 

[Squirrel!]

The phones DAC.

 

[Doxquzme Premium Member]

/\ ditto /\

Only when you use a digital out does it bypass the internal source DAC. In those instances, the receiving device then gets the digital bitstream and uses its own DAC to do the conversion.

 

[Jeff_hires]

/\ ditto /\

Only when you use a digital out does it bypass the internal source DAC. In those instances, the receiving device then gets the digital bitstream and uses its own DAC to do the conversion.

But I am using a digital out - the usb-c on my phone. Problem is, I know that usb-c can carry analog in certain situations.

 

[Jeff_hires]

The phones DAC.

But I am using a digital out - the usb-c on my phone. Problem is, I know that usb-c can carry analog in certain situations.

It is not the phone's dac that's used in usb connection to a head unit. I found this good explanation on androicentral and confirmed on stackexchange.
"with Android Auto the sound output from the phone is purely a digital connection coming out from the USB-C that does indeed bypass your the DAC on the phone. It's just like plugging in an a USB stick with Mp3 files into a car USB port. It will force the system to use the embedded DAC in your car stereo system. Android Auto is also very heavy on the battery, hence the requirement to keep it Plugged in (USB-C is a multi-channel set that can charge & perform other functions as well). It also does use Bluetooth connections but not for music, only for voice calls and etc."

 

[Doxquzme Premium Member]

But I am using a digital out - the usb-c on my phone. Problem is, I know that usb-c can carry analog in certain situations.

Ah, well then, clear as mud.

I have an S23 ultra and a S22 Ultra and when connecting to YouTube, I am able to use a USB-C to 3.5mm adaptor to play music to my passive headphones and earbuds AND my crown amplifier in the my soundroom. That tells me the phone is doing the conversion. None of those devices have an active DAC.

On the other hand, I found this interesting to.

If you want to take advantage of high-res audio on Apple Music, Tidal, or Qobuz, you can use a USB-C to 3.5mm headphone jack (which is what I used) or portable DAC. You can also use an external DAC if your phone is USBC only and doesn't have a headphone output - my android only has USB-C, so contradictory.

There is no question that in my use, conversion is done by the phone. When using my earbuds, my headphones or Pro sound reinforcement set up for my music room, connected from my S22/23 Ultra phones or directly to one of my Crown amplifiers, there's no external DAC in any of those so they can't convert bitstream content.

I have ead additional information on the subject, that there may be a way to dictate via setting - this depending on the phone, but again, not clear.

For now, I know that the signal from my Android playing back MP3s, streaming from YouTube, etc. the conversion is done by my phone.

 

[Jeff_hires]

Ah, well then, clear as mud.

I have an S23 ultra and a S22 Ultra and when connecting to YouTube, I am able to use a USB-C to 3.5mm adaptor to play music to my passive headphones and earbuds AND my crown amplifier in the my soundroom. That tells me the phone is doing the conversion. None of those devices have an active DAC.

On the other hand, I found this interesting to.

If you want to take advantage of high-res audio on Apple Music, Tidal, or Qobuz, you can use a USB-C to 3.5mm headphone jack (which is what I used) or portable DAC. You can also use an external DAC if your phone is USBC only and doesn't have a headphone output - my android only has USB-C, so contradictory.

There is no question that in my use, conversion is done by the phone. When using my earbuds, my headphones or Pro sound reinforcement set up for my music room, connected from my S22/23 Ultra phones or directly to one of my Crown amplifiers, there's no external DAC in any of those so they can't convert bitstream content.

I have ead additional information on the subject, that there may be a way to dictate via setting - this depending on the phone, but again, not clear.

For now, I know that the signal from my Android playing back MP3s, streaming from YouTube, etc. the conversion is done by my

These days usb-c CAN output analog, but that is not the norm. Your usb-c to 3.5mm might have a builtin dac chip. Seems these days many do.
Is your adapter or phone doing the dac conversion?
Below is something I copied from another site...
"Now that 3.5mm headphone output is nearing extinction in smartphones, it's time to start compiling the list for the best USB-C to 3.5mm adapter DACs. Many phones don't even offer analog output anymore on their USB-C output , so the only option is to have a dongle/adapter with a built-in DAC."

 

[Doxquzme Premium Member]

These days usb-c CAN output analog, but that is not the norm. Your usb-c to 3.5mm might have a builtin dac chip. Seems these days many do.
Is your adapter or phone doing the dac conversion?
Below is something I copied from another site...
"Now that 3.5mm headphone output is nearing extinction in smartphones, it's time to start compiling the list for the best USB-C to 3.5mm adapter DACs. Many phones don't even offer analog output anymore on their USB-C output , so the only option is to have a dongle/adapter with a built-in DAC."

Well I'll be damned! Never even considered that they could stick a DAC in something so small - low and behold, I stand corrected!

"This usb c to headphone adapter adopted an advance DAC Smart Chip, offer high-definition audio"

Amazon

Can't link the actual item but here it is - man I feel a little stupid right now!

JXMOX USB Type C to 3.5mm Female Headphone Jack Adapter,USB C to Aux Audio Dongle Cable Cord Compatible with iPhone 15 Plus/15 Pro Max, Samsung Galaxy S23 S22 S21 S20 Ultra, Pixel, iPad Pro, MacBook​

Don't I feel silly!

Cool, then I will get a decent outboard DAC so I can play my electric drums through my Crown - good to go!

Thanks for pointing that out!

 

[Doxquzme Premium Member]

Anybody interested, this a great little DAC for home (OR CAR) equipment. It could be powered in ones car too, uses standard USB charge/power on the UCB-C input.

On Amazon $79

S.M.S.L SU-1 MQA MQA-CD Audio Decoder AK4493S XU316 768kHz/32Bit DSD512 Hi-Res DAC​

 

[Jeff_hires]

Well I'll be damned! Never even considered that they could stick a DAC in something so small - low and behold, I stand corrected!

"This usb c to headphone adapter adopted an advance DAC Smart Chip, offer high-definition audio"

Amazon

Can't link the actual item but here it is - man I feel a little stupid right now!

JXMOX USB Type C to 3.5mm Female Headphone Jack Adapter,USB C to Aux Audio Dongle Cable Cord Compatible with iPhone 15 Plus/15 Pro Max, Samsung Galaxy S23 S22 S21 S20 Ultra, Pixel, iPad Pro, MacBook​

View attachment 56121

Don't I feel silly!

Cool, then I will get a decent outboard DAC so I can play my electric drums through my Crown - good to go!

Thanks for pointing that out!

You're welcome. My main fogginess is when I learned that usb-c can now also output analog. I just wanted to be sure that it was not my phone dac doing the analog conversion. My guess is that when it's plugged into the usb-a going into the head unit that the phone somehow knows (some handshake) that usb-a can't pass analog so it must send digital to the HU Dac. Or can the phone detect the downtream dac? Maybe someone has a more accurate description of what's happening there.
Your phone dac may be better than the adapter dac. Might be good to get a dumb adapter to try, or like you say, get a dac adapter. Good luck. I'll be curious if you get better audio.

 

[Doxquzme Premium Member]

I own one of the S.M.S.L SU-1 MQA MQA-CD DAC. I got it to play off my stable platter CD player, a Pioneer Elite PD-59 that I use as a transport to feed my Elite PDR-99. I was very much impressed with the playback for sure. Brought the old Elite PD-59 unit back to life!