[PaulQinUSA]

This is all new to me. I used to just grab any headphones. I decided to find some better ones and get noise canceling so my next international flight is a little more tolerable. I have been trying out a lot of wireless Bluetooth noise canceling headphones.
 
I tried the QC35s, Sony MDR100X, Sony MDR100ABN, AKG N60nc and now the Sennheiser Momentum 2.0 wireless. I know the Bose and the Sony MDR100X are supposed to be top notch at noise canceling and they certainly were. Unfortunately, I thought the sound suffered. Of those first 4, I actually liked the sound of the cheaper MDR100ABN. But now I am listening to the Sennheiser and wow, they sound great.
 
I have to consider that 90% of the use will be everyday and on the ground. The other 10% will be on a plane for 8-12 hours. I can only buy one pair. As of this moment, it's the Sennheisers. 
 
That's the background...
 
So, like several of the others, these Sennheiser's support Bluetooth aptX. I guess my question is simple - assuming I have a player capable of aptX, do the files themselves need to be lossless to gain any benefit? The majority of my music is in Google Play Music. However, I have a large local file storage of music. Almost all of it is in MP3 format that I would say averages 256kbs.
 
Hope that's an easy question. I'm not really sure how complex this is.
 
Thanks for your help!

 

[Dulalala]

   I guess my question is simple - assuming I have a player capable of aptX, do the files themselves need to be lossless to gain any benefit?

I don't think so from what I understand at least. AptX is just a different way of re-encoding the audio file that is sent to your headphones over Bluetooth. Bluetooth original codec is not meant for audio fidelity, it's main purpose is to transfer the data using as little power as possible which means that it will cut out some data in the audio file to achieve that. The newer codec (claims at least) that it doesn't sacrifice as much data lost through it's new compression.
 
(Anyone with more experience please feel free to correct me as I would like to know as well)