Somebody mentioned that the noise level in HR's concert was high. I haven't been to any HR concert but this was exactly me experience from the Sonu Nigam concert I went to this weekend.
Sonu's singing was quite competent and he was in good form that day. The problem was that the instrumental accompaniment, (particularly the drums) was so loud that not only the lyrics but but also the subtle murkis, alankars etc. were drowned out. In such a situation, voice modulation is impossible because if the singer drops his voice to whisper level for some delicate passage, he will become inaudible because the music is not following suit. Of course, in these types concerts, mithas is of secondary concern. If somebody sings Kajra Mohabbatwala to the accompaniment of snare drum and bass guitar, it is not enjoyable to my ears.
I felt Sonu's best number that day was KANK which he sang with full concentration.