What is the opinion on feeling a tremor in the heart when listening to some reciters of the Quran, and is this considered an attraction to the voice rather than fear of Allah?

Improving one's voice with the Quran is permissible, and souls are inclined towards a beautiful voice. Listening to the Quran from those with beautiful and proficient voices is good and commendable. A beautiful voice is desirable, and the Prophet, peace and blessings be upon him, listened to the recitation of Abu Musa al-Ash'ari and praised his voice. There is no harm in having khushu' (devotional humility) when listening to a reciter with a beautiful voice, while bearing in mind that the voice is a means to understand and ponder the Quran, and that khushu' is for the recited words, not merely for the voice itself. One should continue listening to the Quran and not succumb to the whispers of Satan.