In fact it would take quite a while to catalog all of the differences between these 2 amps. Although they are based on similar circuits, they are quite different in execution. Briefly, the DNA-2 design dates back to the mid '90s, just prior to the company's move to Virginia. The DNA-225 is much newer and incorporates a variety of improvements in circuit design and physical layout. The DNA-2 still has its fans, though, and at a conservative 300W per channel delivers a *lot* of power and authority. Only the new DNA-500 delivers more.
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