The most common and most likely answer to this crossword clue is the 5 plus 5 letter word HEAVY METAL
I've seen this crossword clue in The Daily Telegraph
H
E
A
V
Y
M
E
T
A
L
More clues leading to the result HEAVY METAL
- Mercury's blasted music?
- Lead, for example, in a type of rock
- Big dinner interrupted by tenor ‘singing’ with a loud band
- Mercury perhaps isn’t representative of such music
- Have May let Dicky lead perhaps
- fff pb?
- Some rock and lead, say, have melted and tamely liquefied
- Hard rock yielding lead, maybe
- Lead, say in hard rock?
- What makes use of strong guitar lead, say
Buddy explains!

The straight part
We know that "Some rock and lead, say" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case some rock and lead, say = heavy metal.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.