From Pikipedia, the Pikmin wiki
The Amplified Amplifier (真空波動スピーカー?, lit.: "Vacuum Wave Speaker") is a treasure in Pikmin 2. It is actually a loudspeaker from a stereo, found on the final floor (7) of the Shower Room. Getting it requires fast thinking, as a Ranging Bloyster has to be defeated. After it is brought to the Research Pod, the Hocotate ship uses it to create the Mega Tweeter, which considerably increases the range of the leaders' whistles. Like some other treasures, if the player defeats the Ranging Bloyster, but does not have enough Pikmin to carry the Amplified Amplifier, which requires the strength of 20 Pikmin, it will change weight to match the player's army.
“Today, we searched a deep underground structure that was completely covered in tile! I have no idea what it was originally intended for, but I've decided to call it the Shower Room. Deep within, I clashed with a sleek bug that coughed up this conical curiosity.”
“Your voice is weak. It does not carry. No one notices you. If this is true, then this is the item for you! Starting today, you are a gym teacher! You will never be ignored again.”
“Processing... How odd. The gooey creature dissolved, leaving this curious item behind.
It appears to be coated in slime. Are you sure you want to collect this? ...Absolutely sure?
You'll toss just about anything in my hold. It would be nice if you cleaned occasionally.
This shape is well suited for the emission and amplification of sound waves. A moment, please.
I shall use this as the final part in my new sound equipment. The Mega Tweeter is done!Captain Olimar, this device has increased the acoustic range of your whistle!”
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