Which DAC is being used with Bluetooth?


Might be a silly question but when I Bluetooth from my phone to my Cambridge integrated Amp Cxa80, the Dac that is being used , is from the iPhone still right? I have a Wadia 171i transport that has a digital out to the DAC In The amp but the sound quality from the Wadia plugged into the amp just sounds slightly better than the Bluetooth option. I’m using a fairly inexpensive no name brand optical plug from the Wadia to the amp... would upgrading to a carbon AudioQuest coax cable from the transport to the Amp make a more noticeable  sound difference? (I have an AudioQuest NRG 3 Y power cable coming in the mail for my 1st power plug upgrade, hoping for sound improvement there too.)

My rig is CxA80 cambridge intregraded 120 watt to 4ohms amp, Dyanaudio DM 3/7 towers, Wadia 171i transport from
 the phone to the dac into Amp, Shunyata venom conditioner plug into $10 power strip with no surge protection.... ( surge protection is from the Shunyata plug) and a low grade Klipsch 12 in Sub( like $250 range from Frys, forgot the model).
Thanks for reading and any advice you can send my way.
rmiller01
My bias would be no, the cable won’t make that much difference.  Of course, until you try it, we can’t know for sure...Can you by an expensive quality cable with a return policy?  Even if there is a restocking fee?  At least that way you would satisfy you curiosity.
  Does your Cambridge amp have a usb input?  If so have you tried comparing the phone without the Wadia plugged directly into the amp/DAC?  That would remove the Wadia from the equation.
I have plugged the phone  into the amp without the Wadia before, and it’s souds pretty crappy. The Wadia is difinately better than analog plugged in the front of the amp. So yeah I can look into returning a more expensive coaxial plug if it doesn’t improve the sound too much. 
Thanks.
That’s interesting I am guessing that the DAC in the Cambridge doesn’t do much in the way of jitter reduction and that the Wadia does.  That was my experience with my iPod and the Wadia as well.
well, if upping the cable doesn’t do much, it could be that the latest Bluetooth technology as implemented by CA is really good.