i go to china to buy fireworks often and see some of the manufactures making fireworks for disney (they keep a lot of the designs, colours very hush hush) not sure if all of stock is made or just certain products but quality comes with a price the time fuses can be made so exact. it's more easier than it used to be as china have moved from 100% humans to 70% machine made. As a firework display designer myself in UK, shows have got easier and easier over the years. computers have made the most complicated show design easy. we have tried magic fire igniters (the same disney uses) and they are very expensive. so it's not surprising they are not used on all the fireworks.
one of the most biggest problems all displays have over such a large area is sound. disney do have a upperhand with this as they zone off each of the areas with speakers and no need to delay the audio, normally if you have speakers at the front of a audience sound takes time to travel to the back so 100m back could be 1 sec late making it look like the fireworks are out of sync. since disney zone of all the areas they can make sure all the audio reaches the audience at the same time. but i expect some zones are not as covered as much as others.
2 things fireone uses one is timecode to sync the show which is very old technology, sometimes it's possible to go out of sync. not so much of a problem as less user error can be made considering they dont need to disconnect equipment like any normal show but it has been know to happen. The second is a manual delay users can set if they feel the show is out of sync. The problem you get with both is comets have no delay so when it is fired you see the effect. shells on the other hand have to pre fire time, this delay is set by disney when the fireworks are made and if they are not exact with whats on the computer you end up with the computer setting off the prefire time early or late. disney can make a perfect show but they are only as good as the manufacture that makes the fireworks.
i find it funny seeing figures of $30k to 60k per night on fireworks per show. trust me if they even spend $8k, id be surprised, fireworks are cheap and if there is one thing iv learnt from disney is they know how to use very little fireworks and still give the best show ever. if you took away the storyline, the music, lights, special effects and you would have quite a small fireworks show but all together you have the very best show in the world.
