boom box

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun A portable audio system with speakers capable of producing loud sound.

from the GNU version of the Collaborative International Dictionary of English.

• noun a large portable casette or compact disk player, usually having an integrated radio receiver. It typically has two (stereophonic) speakers, and can be adjusted to play at a high sound intensity, from which the name comes.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun A powerful portable audio system for listening collectively to recorded or broadcast sound.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun a portable stereo