Were you using both the Tidal vs Amazon apps or the browser?
The biggest issue with Amazon Music isn't the sound quality. The app sounds really good and you have the ability to play back in Exclusive Mode which bypasses OS based sound processing. The issue is getting it play on the stereo. The app is proprietary and has limited device support.
I found Tidal didn't have the music selection I listen to and to and I'm not a MQA guy so after the fee trial I went another direction.
Just a side note the annual family plan for prime members is really hard to beat.