Three types of power supplies commonly used in Audio

Batteries...
Either “one time use” or rechargeable

Batteries, especially the rechargeable type, are pretty much an ideal power source for audio components if they are correctly sized. A battery is a reliable source of clean, quiet power. That is if the battery is large enough to power the component for a reasonable time without significant discharge. One problem is that the impedance of a battery increases as it discharges, the higher the impedance the faster the rise in voltage ripple. If the frequency of the voltage ripple is in the audio range then this can cause undesirable noise to be heard from the component.

Another obvious con for battery powered systems is the constant requirement for either replacement or recharging.

Wall Wart power supplies...
This is the little black box supplied with your Firestone Audio Component (FAC)

The standard wall wart power supply is a non linear, unregulated power supply; these are the simplest and least expensive solution for powering your Firestone product.

With the wall wart you have 120VAC going in and 24VDC coming out (assuming a stable 120VAC source). It includes a rectifier to convert the AC power to DC and a smoothing circuit to help tame the pulsating DC. Unfortunately there is still a significant amount of ripple on the DC side and the small space available in most wall warts limits the amount of filtering that can be used to reduce the ripple. The result is degradation in the DC power and a corresponding degradation in audio quality.

Another problem with an unregulated power supply is that the output voltage will rise and fall with changes to the input voltage. Any variation on the AC input side will be directly translated into DC variation on the output side. If your AC wall power has hash, surges, spikes, brown outs or some other ugliness; this will appear on the DC side as well and degrade the audio quality. These DC artifacts are known as noise and ripple. Fortunately your FAC is equipped with ”power regulation” and “low pass filter” circuits to help minimize the bad effects of this.

Last but not least is the low power output capability of the wall wart. Electronics that are “power challenged” tend to sound thin or flat at frequency extremes and don’t have the oomph to follow the peaks and large dynamic swings in the music. The FAC’s as with any audio component will draw considerably more current during intense passages in the music; this is when the wall wart may not have the jam to follow along.

Linear, Regulated Power Supplies...
This is the SUPPLIER Power Supply upgrade.

To help deal with the AC voltage variation and other assorted nastiness from the wall power, the Firestone engineers designed the SUPPLIER power supply. The SUPPLIER is a linear, regulated power supply so this means the DC output voltage is largely independent of the AC input voltage. It is designed to output a stable 24 VDC despite variances to the AC input voltage. Is it perfect? Of course not, but it’s a major improvement over the relatively large voltage swings seen at the DC output of a wall wart.

The Supplier also has vastly superior filtering for both DC ripple and noise. This is where you’ll experience a majority of the increase in sound quality; tighter bass, clearer highs and a better defined midrange. To my ear the biggest improvement is in the dynamic contrasts, dynamics are noticeably improved. Also, if your system can reveal it you’ll experience an increase in the magical, low level detail as the line noise and hash present with the wall wart are filtered away by the Supplier.

The SUPPLIER also has much higher power output and superior reserve power compared to the wall wart. Its high current output effortlessly follows the music regardless of dynamics and helps your FAC deliver the very best from the music.

So is it really worth the EXTRA COST?
YES, with one exception. If you are using the Fubar II with a low resolution system then the improvements may not be as apparent. I personally can detect the addition of the Supplier 100% of the time in my system in an A - B - A test; all I have to do is listen to the low level detail in the music.

Chao...