tannerite is an interesting choice, 80lb of tannerite was a very interesting choice
i did mention metal+oxidizing agents elsewhere, the one above is relatively stable and needs a decent shock to set it off (HV round, det cord or a det) but it will self tamp and is rather energetic for its mass
as a playing card size target for long range shooting it only needs a small bit in a pouch or tin for a bang and a flash if you get a bullseye
a telescope is quieter
80 lb is getting close to a blow and suck booster in a torpedo warhead, although that is usually done as a mix, but it has been done with separate components and neat shapes
ps videos of a moderate amount in a piano are available on YouTube for any unfamiliar with such madness
3lb seems adequate for a piano
i recon this was quite a banging gender reveal party