There is certainly a small loss. Not audible in my opinion. However, the quality of the headphones is much more important. In the meantime, even the top league headphones offer Bluetooth transmission. The freedom from cables is a big plus point in many situations.

Transferring music via Bluetooth to a Bose speaker leaves nothing to be desired. Rich sound with all the highs and lows of the music stand comparison with CD quality. There may be losses, but for that you would have to have the appropriate measurement technology or perfect hearing. What you hear as a normal music connoisseur sounds very good.