Thank you for your critical review , just quick question , is there any special reason for your choice of iphone XR ? XR need special connector for T4 , and may be not good for your review . Of course , I understand you may show the performance of T4 in portable musical playing . No any offence. And I do agree with your final conclusion that However, it is becoming hard to rec the T4s today with the release of so many great earphones and IEMs in the $100 - $200 range.