The ProPower™ PSW152 was developed using the expertise of professional sound engineers and working musicians. You will find your new Nady audio speaker has superior performance and greater flexibility than any other subwoofer speakers. We recommend that you read this instruction sheet carefully to get the most out of your new unit. Thanks for selecting NADY AUDIO and the PSW152 as your choice in subwoofer speakers. Ruggedly built, exceptional sound - the ProPower™ PSW152 from Nady audio delivers the best value in subwoofer speakers.