Possible Clues:

• *Megadeth's music genre
• What makes use of strong guitar lead, say
• Arsenic, for example — a noted conversation stopper?
• Type of rock like lead?
• Some rock and lead, say, have melted and tamely liquefied
• This is Spinal Tap's kind of music
• Hard rock yielding lead, maybe
• Lead, say in hard rock?
• Music played by certain bands, not steel or brass!
• Iron, e.g. ... or Iron Maiden's music genre