Audiolab 6000A & Wireless Headphones

[Smiffy1]

Hi, I am looking at purchasing Sonys WH-1000XM3 wireless headphones to use with my Audiolab 6000A amp. In terms of audio quality what is the best way to connect a B/Tooth transmitter to the Audiolab, via the pre - outs or headphone socket ? I have looked at Sennheisers BT100 product. Thanks