My guess is both a more rigid chassis and an improved / sturdier power supply. While the improvements to chassis construction can be debated, a sturdier power supply will typically be audibly obvious if one knows what to listen for. This becomes more apparent as the speakers are more difficult to drive and / or volume levels ( dynamic and / or sustained ) are increased.
As a general rule, other than really big heatsinks and / or thick faceplates, a heavier amp is typically "better" than a lighter amp of equivalent power rating. Since all of the power that the amp produces comes from the power supply, skimping there will produce both audible and measurable differences everywhere else. Sean
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As a general rule, other than really big heatsinks and / or thick faceplates, a heavier amp is typically "better" than a lighter amp of equivalent power rating. Since all of the power that the amp produces comes from the power supply, skimping there will produce both audible and measurable differences everywhere else. Sean
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