Reb Yakov Lemmer is the greatest chazan alive. I have listened to many many chazanim, Alberto Mizrachi used to frequent my house when we were in yeshiva together 50 years ago. Many chazanim have power, dynamic range, control, melodiousness, and other attributes of proper voice. But Yanky in addition to possessing all those attributes and near the top in all of them has one up on all but a select few of the others. He has perfect pitch. If you listen carefully to the others, their pitch will go off on occasion, especially in key transitions. Lemmer is perfect in this respect; and the only one who is consistently so.