As you've probably heard by now, Piranha recently undertook an awesome project in North Wales (which is quickly becoming our favourite place by the way) in which we collaboratively installed the new interactive and immersive tour for Llechwedd slate mine. One of the things that makes this tour so special, is the way in which it transports guests back in time, to an era where slate mining was still an important industry for the area, and the mine at Llechwedd was still fully operational.
As a part of this project, ourselves and the install team were tasked with creating a simulated explosion for one of the larger chambers. Cool, I know. The general idea was to recreate the blast of a gunpowder explosion as it might have felt in the process of mining (without the risk of potential death or smoke poisoning).
And here's how we did it...
Thanks to our friends at Weigl, interactive control technology is made both possible and seamless. Our engineers programmed Weigl's ProCommander 2 to sequence the sound, lighting and special effects of the explosion. The in-house team at Llechwedd then created a detonator, which guests would be able to use to start the explosion themselves.
This road-runner style detonator (can anybody say Wile e Coyote?) is easily recognisable to all ages, and means that everyone can get involved and engaged, from the oldest to the youngest.
Our engineers fitted a micro-switch arrangement into the detonator which is wired back to the ProCommander, which is then programmed to trigger the explosion. That handsome devil is our fearless leader in the process of installing it.
You've heard the saying 'there's no smoke without fire', well we beg to differ. In order to make the explosion seem convincing, there needed to be a significant amount of smoke, and it very definitely needed to be without fire. To achieve this we installed a smoke machine (unsurprisingly) and a high-volume commercial compressor. When the detonator is, well, detonated, the smoke machine is triggered to release it's smoke. The compressor is then triggered to begin it's exhaust funnel cycle and the smoke is sucked into the compressed airflow in the direction of the guests on the tour. This way guests are engulfed in a cloud of smoke, much like the miners would have been, immediately following an explosion.
Whilst fire was clearly not an option, it would be fair to say that a detonator and a cloud of smoke do not an explosion make. A combination of blinders and LED coloured lighting was installed to create the startling flash and afterglow, typical of a gunpowder explosion. 1000 watts of PA (so quite a lot) were also installed to simulate that deafening sound, including a sub bass to provide the fundamental rumble.
I suppose I should apologise for misleading you with the title of this blogpost - we aren't actually twisted fire-starters; just really good at faking it.
For any of you avtweeps out there who want to know a little more about the technical considerations of putting this kind of SFX in an enclosed space, keep reading; otherwise, feel free to jump off now and tell your friends about those cool folks at Piranha who can give you (or your guests) the experience of a gun-powder explosion 500ft below ground.
The fiddly bit:
Clearly, due to the kind of space we were working in, the physical parameters required a lot of thought and negotiation. One of the main obstacles for consideration was how to stop the smoke from lingering in the enclosed space where the 'explosion' would occur. Depending on the prevailing winds, the airflow through the underground tunnels could draw the leftover smoke towards guests who hadn't yet reached this stage in the tour, giving an unwanted preview of what was to come, but also spoiling the view of the incredible underground caverns. In order to rectify this, we installed a rapid air dispersal solution to stop the chambers filling up with smoke and to deal with the potential problem of overflow.
As well as the spacial issue, we were also working with far lower temperatures than are usual for AV installations, and as such had to contend with a decreased dispersal rate. In other words, an amount of smoke that would have dispersed within 30 seconds above ground, is likely to last several minutes underground. This might not seem like a huge difference, but when tours are running every 15 minutes, every second really does count. Our engineers experimented with multiple variations of mist/smoke solutions until they found the variant that achieved the right result, within the right time-frame.
So if you haven't yet made your way to Llechwedd to experience the new tour, why not? And if you're reading this thinking that your attraction could do with some SFX to give it that 'explosive' quality (see what we did there?) then we'd love to have a chat with you.