to increase the strength of sound using electricity

increase in size or effect

to establish, give legal authority to, (a committee etc)

comprise, form

to add to (the value, attraction, reputation etc)

improve, embellish

to improve something in quality, flavour etc (using something)

improve, embellish

to fill (a tyre, balloon etc) with air or gas

blow up, increase

to make (a profit, opportunity etc) as large as possible

blow up, increase

to make (one's estimates) too large

blow up, increase