Let me quote from the Bolder Cables website for you. It is only one of two or three places you can get this mod done, and the only one I have first hand experience with.
Short answer is that probably the most important thing to do is clean-up the power supply. Besides Wayne's very reasonably priced mods, you can also get one from Wellborne Labs.
After that if you want to get the most out of the unit, because you have golden ears or a highly resolving system, the digital and or analog mods both add a lot and IMHO are well worth it.
http://www.boldercables.com/servlet/Detail?no=369
The SB3 digital only mod has many of the main input power supply capacitors and the digital buffer's power supply capacitor replaced with higher value, low ESR versions. BlackGate NX caps are used throughout the circuits.
Our latest version of the SB mod now includes changes to the internal switching supply that provides voltage to the display. In the past, this supply has added quite a bit of noise to the positive voltage and ground paths. We have changed the circuit to reduce this noise. This results in a quieter "Blacker" background
The power supply cap to the digital buffer chip is replaced by a BlackGate NX. The signal path to the digital output jack is rerouted. The digital output jack is replaced with a 75 ohm, WBT NextGen, gold plated, copper RCA.
There are options to install a Bybee Slipstream Purifier in the digital signal path. You have your choice of Copper or Silver Slipstream Purifiers.
Short answer is that probably the most important thing to do is clean-up the power supply. Besides Wayne's very reasonably priced mods, you can also get one from Wellborne Labs.
After that if you want to get the most out of the unit, because you have golden ears or a highly resolving system, the digital and or analog mods both add a lot and IMHO are well worth it.
http://www.boldercables.com/servlet/Detail?no=369
The SB3 digital only mod has many of the main input power supply capacitors and the digital buffer's power supply capacitor replaced with higher value, low ESR versions. BlackGate NX caps are used throughout the circuits.
Our latest version of the SB mod now includes changes to the internal switching supply that provides voltage to the display. In the past, this supply has added quite a bit of noise to the positive voltage and ground paths. We have changed the circuit to reduce this noise. This results in a quieter "Blacker" background
The power supply cap to the digital buffer chip is replaced by a BlackGate NX. The signal path to the digital output jack is rerouted. The digital output jack is replaced with a 75 ohm, WBT NextGen, gold plated, copper RCA.
There are options to install a Bybee Slipstream Purifier in the digital signal path. You have your choice of Copper or Silver Slipstream Purifiers.