ParticleSoundSystem-Template

using System.Collections.Generic;
using UnityEngine;
using System.Linq;

[RequireComponent(typeof(ParticleSystem))]
public class FireworksParticleSoundSystem : MonoBehaviour
{
    private ParticleSystem _parentParticleSystem;

    private IDictionary<uint, ParticleSystem.Particle> _trackedParticles = new Dictionary<uint, ParticleSystem.Particle>();

    void Start()
    {
        _parentParticleSystem = this.GetComponent<ParticleSystem>();
        if (_parentParticleSystem == null)
            Debug.LogError("Missing ParticleSystem!", this);
    }

    void Update()
    {
        var liveParticles       = new ParticleSystem.Particle[_parentParticleSystem.particleCount];
        _parentParticleSystem.GetParticles(liveParticles);

        var particleDelta       = GetParticleDelta(liveParticles);

        foreach (var particleAdded in particleDelta.Added)
        {
            //Todo: Play "Spawn" sound - use particleAdded.position to play at right position
            Debug.Log($"New particle spawned '{particleAdded.randomSeed}' at position '{particleAdded.position}'");
        }

        foreach (var particleRemoved in particleDelta.Removed)
        {
            //Todo: Play "Disappear" sound - use particleRemoved.position to play at right position
            Debug.Log($"Particle despawned '{particleRemoved.randomSeed}' at position '{particleRemoved.position}'");
        }
    }

    private ParticleDelta GetParticleDelta(ParticleSystem.Particle[] liveParticles)
    {
        var deltaResult = new ParticleDelta();

        foreach (var activeParticle in liveParticles)
        {
            ParticleSystem.Particle foundParticle;
            if(_trackedParticles.TryGetValue(activeParticle.randomSeed, out foundParticle))
            {
                _trackedParticles[activeParticle.randomSeed] = activeParticle;
            }
            else
            {
                deltaResult.Added.Add(activeParticle);
                _trackedParticles.Add(activeParticle.randomSeed, activeParticle);
            }
        }

        var updatedParticleAsDictionary = liveParticles.ToDictionary(x => x.randomSeed, x => x);
        var dictionaryKeysAsList = _trackedParticles.Keys.ToList();

        foreach (var dictionaryKey in dictionaryKeysAsList)
        {
            if (updatedParticleAsDictionary.ContainsKey(dictionaryKey) == false)
            {
                deltaResult.Removed.Add(_trackedParticles[dictionaryKey]);
                _trackedParticles.Remove(dictionaryKey);
            }
        }
        
        return deltaResult;
    }

    private class ParticleDelta
    {
        public IList<ParticleSystem.Particle> Added     { get; set; }   = new List<ParticleSystem.Particle>();
        public IList<ParticleSystem.Particle> Removed   { get; set; }   = new List<ParticleSystem.Particle>();
    }
}

It's very interesting. I'm also making my own fireworks game, and I solved the problem of fireworks audio in my own way. But in the process of searching for how to generate smoke for each fireworks particle, I found here.

@Alfafar
Ok cool. Yeah in my game I have an bit more advanced version now, to avoid using too much memory etc. But the idea is the same.

How did you solve it, not in code, just the concept?

I call the emit method in the script to emit particles, and then calculate the start and end positions in real time, and set the delay of playing sound effects or special effects.