"exploding guitar amp"

[malibu]

The scene calls for an amp that "explodes" because it is turned up too loud. high school theater/high school budget...

I cant use smoke, can use dry ice, can possible just have someone run on the stage with a co2 fire extinguisher to "put it out".

What would you do?

[JohnEstep]

I'd think for going on the cheap if you can, however you have it fall apart, some kind of powder could be used, baby powder, flour, that kinda thing, that when it falls apart "explodes" a poof of dust goes out. Another speaker mounted behind it could give a really good sound effect of it falling apart. If someone is standing close to the fake amp they could possibly put a foot on top of it when it goes, releasing a catch and causing the whole effect.

[Van]

Originally Posted by JohnEstep

I'd think for going on the cheap if you can, however you have it fall apart, some kind of powder could be used, baby powder, flour, that kinda thing, that when it falls apart "explodes" a poof of dust goes out. Another speaker mounted behind it could give a really good sound effect of it falling apart. If someone is standing close to the fake amp they could possibly put a foot on top of it when it goes, releasing a catch and causing the whole effect.

NEVER USE BABY POWDER IN A DUST EFFECT!
I've posted it a bunch of times on here. But since you're new I'll let it slide,
Your best option is Rye flour it's the least allergenic < I don't know if that's the right way to say that.> and it's Equity acceptable. Baby powder is Talc, Talc and Asbestos come from the same mines. Talc will tear up your lungs the major difference is that it doesn't cause Cancer.
Cornstarch is another viable option but it and most other Powdered items, baking soda, baking powder, etc. tend to clump if exposed to high humidity, like say, fog .
Just my two cents.

[dvsDave]

Hypo-allergenic is the term you are looking for. And this is a big concern in a world where somehow kids develop horrifying reactions to a single particle only a thousandth of a millimeter in diameter.

* dvsDave stomps on his rant about germophobic parents before he gets started.

[sk8rsdad]

Consider using fuller's earth rather than organic materials like flour. Fuller's earth is a common ingredient of kitty litter.

Organics are a poor choice for a lot of reasons like health, hygiene, critters, and combustion. Google "flour explosion" for hours of amusing videos.

[kiwitechgirl]

I'd build a box and dress it to look like a guitar amp, and rig it with hinges and hinge pins so that the sides can collapse (ie hinged at the bottom, and then with removeable hinge pins holding the sides to the top). Get clever with fishing line so that a crew member can pull the line to remove the hinge pins, causing the sides of the box to collapse. Inside the box, I think I'd put an inflated balloon which also has some safe dust-producing material in it (there are already some great suggestions here!), and somehow work out a way to burst the balloon with the fishing line trick - shouldn't be too difficult to rig a thumbtack or pin or something to burst the balloon. Be aware that if you have a crew member run on stage with a fire extinguisher to "put it out" you're going to have to get the extinguisher refilled for every show which will probably blow your budget....I would think with the collapsing box and a burst of dust, you should hopefully get the effect you want!

[AdamBair]

I would go with a flash bulb or strobe light set inside the amp. Maybe you could pipe in the CO2 from the fire extinguisher if you can cut a whole in the back of the amp. But then that extinguisher would need to be recharged before it counts towards fire safety again.

If you dip the general lighting at the same time as the strobe flash, the "explosion" effect feels much larger. A quick puff of smoke out of the amp would be a nice touch.

[eternalfire1244]

The first thing that came to mind was using compressed air. It would be trivial to simulate a power cord with the air hose. The hose would have a valve offstage for someone to trigger, you could use the air to launch the powder via a small tube like a pen or bigger if more dust is needed. If the intent of the effect is to have the speaker "Jump" out of the cabinet, the face plate could be taken off and preset to fall either because of the air pressure or cast intervention as could the speaker as long as it was unscrewed and was close to coming apart. I would use a medium or large christmas tree light (Clear or amber) to simulate the transistors.

[Chris15]

Originally Posted by eternalfire1244

I would use a medium or large christmas tree light (Clear or amber) to simulate the transistors.

Not to nitpick too much, but transistors don't light up unless things are very wrong...
Triode valves in the other hand...

[eternalfire1244]

Thanks for the correction. I always get the parts mixed up with some older tech. The last time I saw a vacuum tube transistor was at a local HAM radio flea market ( Put on by LARCfor any interested HAMs out there).

On a side note isn't the point of this effeect to simulate things going "Very wrong"?