1. 佢的輸入係「a single ended analog input signal and splits it into two signals 180 degrees out of phase, one with the positive polarity the other with negative.」即係根本唔係bal. in,就算佢的設計點好,都係受到input所限。
2. 留意佢的輸出頭並非常用頭,加添diy的問題,同時要破壞原本earphone的頭,多數會令earphone失去保養,即使rsa的機係lifetime 保養都無用!earphone壞左,有amp都無用。