Echo cell

Echo cells are gadgets from the Marvel portion of the Generation 1 continuity family.

AUGGH! Why did I think of trying to use 'Agadoo' against him?

An echo cell is a piece of technology that absorbs sonic waves and redirects them outwards. It also helps with ventriloquism.

Fiction

Marvel Comics continuity

Marvel UK The Transformers comic

An echo cell was built into Buster Witwicky's battlesuit by Wheeljack.

When Buster used the battlesuit in battle against Frenzy, he unknowingly activated the suit's echo cell, absorbing Frenzy's sonic attack. The absorbed attack was then fired out, incapacitating the Decepticon. Robot Buster!

In the alternate future of 2008, Hot Rod used an echo cell to trick Ghyrik with ventriloquism. Space Pirates!