Was this student in the wrong?

I'd say you were both in the wrong.

Its never permissable to turn the sound up full volume no matter how many vote yes. The sound can go up at home IF it is not bothering anyone at home.

His sense of manners is backwards. It doesn't matter how many want it. What matters is if anyone doesn't like it. If no one thinks its a problem then it's okay. If it was a hot day and no a/c and they decided to sit around in the nude it doesnt matter if the majority thinks its okay. If one person finds it offensive then they are in the wrong to do it. It doesn't matter, nude or sound volume, if you are in a public place and someone takes issue with it then it shouldnt be done.

As for you, who gave you permission to leave the school grounds? Is your school 1 room only? Could you not have moved to another class room or gone to sit in the office or gone to sit in the library or gone to sit outside somewhere or gone to the classroom where the teacher was and waited outside? If the volume was that high surely the teacher would have heard it and come back or you could have found another teacher to tell them to turn down the sound. Going home was a juvenile response. It's like a 2 year old stamping its foot and throwing a tantrum for not getting its own way.

The solution is very simple, and I wish I had thought of it back when I was your age: disposable earplugs. Carry them wherever you go. Only ~$0.5 apiece at a pharmacy and frankly can be reused several times without reduction in effectiveness.

Last week, for 4 nights in a row, there were these kids shouting and detonating explosives outside my window every hour from eve till early morn (and then during the day). Not one constable showed up to tell them off (let alone take measure against their antics).
What keeps societal structure from degenerating into anarchy are three variable demands from the individual: enforcing the rules, maintaining personal space and tolerance. They must be balanced according to the population, both to the side of preventing rebellion and physical constraints of proximity or inspiring empathy.
You have the mien of highschool or college. That's part of what some guys do, particularly in this century, owing to the double edged sword of technology. If you lack the authority to persuade them, you find ways to deal with the problem. Justification for your perspective can only lead to frustration over the triumph of evil, so to speak. As stated, enforcement is only a part of your sanity's defence, far from a personal bodyguard.

Best course of action would vary depending on the person with whom you have beef, but I think claiming you were left without an alternative is a tad on the dramatic side.