This article lists manufacturers of bass amplifiers, loudspeakers, and other amplification-related items such as preamplifiers.
This distinction affects the design of the loudspeakers, the cabinet, and the preamplifier and amplifier.
Loudspeakers for bass instruments tend to be larger and more heavy-duty, and speaker cabinets have to be built more solidly to prevent unwanted rattling due to the low frequencies.
At the other end of the spectrum are companies that offer bass amplification equipment as part of a much broader offering of different types of instrument amplifiers and public address systems (e.g., Peavey, Carvin A&I or Yorkville Sound.)
Another way of categorizing bass equipment manufacturers is by which part of the market they are targeting.