Actually this has been answered in a different domain with single question surveys such as for job satisfaction.
Psychology research has shown and well established that a single question, how satisfied are you with your job, gives a reliable and valid answer without needing further elaboration. Typically it is measured using a five or seven point Likert scales, with 7 point scales marginally better.
So, translating this finding to pleasure levels with music, the question might be asked,
Rate (this) music (experience) by answering the following question:
How pleasurable (or pleasing) is (this) music (experience) for you?
1. Very Highly pleasurable
2. Highly pleasurable
3. Moderately pleasurable
4. Neither pleasurable nor displeasurable
5. Moderately displeasurable
6. Highly displeasurable
7. Very highly displeasurable
Framing of the question would need to be tested, and adjusted for word choice, settings and so on, as well as choosing asking about liking vs wanting vs pleasure vs preference and so on...
Measuring the brain is unnecessary invasion, and doesn't use probes, but neuro-imaging, for example here: https://www.sciencedirect.com/science/article/pii/S0896627315001336
And there are other full scales such as Temporal Experience of Pleasure Scale, available that are not really justified here.
So, in sum, just ask...How pleasurable (or pleasing) is (this) music (experience) for you?
;-)