What is an SP Capacitor Pack?
The SP capacitor packs from Angela - Gilbert Yeung are specially constructed banks of capacitors to greatly increase the power reserve of the preamp or line stage of an audio component. The size and composition of the capacitors is specific to the model of SP Capacitor Pack and have been carefully selected over years of A/B testing for the best performance and what it does for the sound.
SP Jack
Many models of components from Gilbert Yeung come preinstalled with an SP jack for a plug and play upgrade option. To use SP, simply plug the pack into the rear mounted jack with the device off, then power on the device. Devices with an installed SP jack contain an integrated high current soft start circuit to safely power up the large reservoir of energy. Once the indicator is at full brightness and the relays have engaged, the cap pack has fully charged and is bonded to the power supply.
Where the FCF focuses on the output stage of a component such as in power amplifiers, the SP pack adds a large reservoir of energy to the line stage or preamplifier stage of a component.
The Sound and A/B Testing
Each SP capacitor pack is burned in for a period of time after completion, but the pack will still need some time for the capacitors to fully settle and it is normal to note some changes in the sound as this happens.
Once you have connected the SP cap pack through the associated jack and turned the component on, wait for the pack to fully charge. Once it is charged you can instantly A/B the difference that it makes in your system by disconnecting the cap4 pack from the device, and plugging it back in. Depending on the size of the pack there is a 3-5 minute window of time that you can plug the capacitor pack back into the component for instant A/B comparison, otherwise you will need to power off the device again as to not create a spark upon reinsertion.
The capacitor packs add a new level of dimensionality and palpability to the soundstage and imaging. Similarly to using an amplifier with abundant headroom, a capacitor pack gives your component that headroom and immediate power that is not capable from the wall alone, and allows the circuit to perform unhindered. The soundstage blends in behind the speakers and gives more weight to the center image, allowing you to pinpoint finite details and locations of instruments easier. Unplugging the pack you can immediately notice these effects start to collapse as if you were walking away from the stage, plug the capacitor pack back in and it all comes back into focus. While instant A/B is a fun exercise, you will find it hard to not have it in your system once you have heard it.
Pictured is a Gilbert Yeung DAC with SP jack
The Science
Adding a capacitor pack does much more than just increase the internal reservoir of DC power. All conductors are 14 gauge copper for high current capability ensuring that regardless of the load or demands of the amplification stages, the power supply will not sag, and it will always have more than enough power than it needs on demand for increased dynamics and stability through musical transients. The greater the amount of capacitance, the lower the input resistance of the individual electronic components trying to pull from it, providing something that no power cable or audiophile fuse or tweak can. Even better is that this can be instantly compared back and forth for the pronounced effect that it has. Where the FCF helps an amplifier handle transients and occasional high current requirements, the SP pack helps clean up the power for some of your most sensitive components such as preamplifiers, so that they are essentially running off of battery reserve power, compared to the noisy and inconsistent power from the wall.