That is the beauty of the Vandersteen subs. You use the M5-HP crossover or get the fixed value crossovers. These are connected to the speaker outputs of your amp and allow the subs to work seamlessly with your speakers and relieve the amp from having to reproduce the low frequencies which are the most demanding.
When in doubt, call or message audioconnection, Johnny Rutan. He can give you the best advice on everything Vandersteen.
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