Every Audiophile knows that a source of clean, regulated power is essential for great sound. The standard wall-wart power supply included with your Firestone Audio component is a capable unit and will satisfy the needs of many listeners.
The "SUPPLIER" upgrade on the other hand is a highly regulated, linear power supply capable of delivering Audiophile grade power to your Firestone Audio headphone amps and DACs. This is the clean power you need to follow the dynamic swings and crescendos in the music for a noticeable improvement in sound quality.
Electronics that are "power challenged" sound thin or flat at frequency extremes and don't have the oomph to follow the peaks and large dynamic swings in the music. This is particularly noticeable at higher frequencies and when driving some of the more difficult headphones.