This listing provides a set of six capacitors, with an option to add two more, high-voltage capacitors. Six low voltage capacitors address the common issue of hum that develops after several years due to weak components in the Sunfire HRS series of subwoofers: 8", 10" and 12". This kit has also been used successfully with D12 subwoofers (Dominator).
Optional: The two high voltage (originals are 160V; upgraded to 200V Nichicon LGW series) 1000 uF replacement capacitors are also available to be added for those who want to be more thorough (marked C65 and C76 on the power supply board).
The six low voltage capacitors are new Panasonic FR low ESR or Nichicon low impedance capacitors. Photos of their location are shown in this listing. Included instructions identify their numbers on the circuit board, too. Desoldering and soldering is required for installation. The replacement capacitors are a bit larger than the originals (taller or a bit wider), but I have used them in these amplifiers. Most of the capacitors have higher voltage rating. Some Kester solder is included in the kit.
There is an alternate design for the power supply circuit board. The components to replace are the same, but the identification numbers on the circuit board are different. The two 47 uF 16v original capacitors to replace in that case are numbered C4 & C5.
\A Tip on Large Capacitor Replacement:
First, discharge any residual electrical charge in the two 160V 1000 uF capacitors.
Second, desolder both
pins, so that ONLY adhesive is holding the capacitor. You don’t want to pull a
copper socket out of the circuit board’s holes. If you are sure the
terminal/pin is not stuck to the board, then I would gently pry one side of the
capacitor up. Warming the board with a heat gun (not too hot) can loosen
adhesive and make it more flexible. If there is a chance one or both of the two
pins may be still soldered to the sides of the socket, I would use a soldering
pencil to heat the terminal closest to the side I am trying to loosen, so that
I know the solder is not holding.
Then alternate sides to incrementally back the capacitor up and away from the board until both pins are free and the capacitor is out.
Other Troubleshooting Tips
1) It is rare, but if the subwoofer produces distortion as volume increases (it may sound like the speaker/driver is loose or rattling), there may be two small 470 uF 16v capacitors that have degraded in the amplifier section. Each is mounted to a 1" x 1.5" daughter board, and is easy to spot, but they are not easy to access for desoldering and soldering. You might spot the aluminum cans bulging--a sure sign they have failed. I can create a custom listing if you need those two additional capacitors. I have mounted the larger 470 uF capacitors on the bottom of one of those two boards, to fit. The eighth photo in this listing has a screwdriver pointing to one of those daughterboards and its larger, replacement 470 uF capacitor.
2) Inconsistent volume, or lack of power may be due to the volume potentiometer wearing out or breaking (infinite resistance to the center contact). Cleaning the potentiometer has not been a long-term solution, and that original physical size is not available as a drop in replacement. I have found some new replacement potentiometers that are the same resistance and can be mounted to function correctly, though in order to fit, they must be installed upside down, so that their three terminals connect to the circuit board with short, soldered jumpers. I may add a replacement potentiometer option to this listing in the future. Let me know if interested.
3) If you measure a small transistor in the power supply and find it has shorted (rare, but I have seen it once or twice), I have a few in stock. It is not a common problem, but if it shorts, it will need to be replaced (along with the capacitors in the kit).
From a previous buyer, July 2023: "Yes i saw that 2 out of the six caps were swollen upon disassembly. I replaced all of them tonight in about 2 hours time. I plugged it back in and I couldn't be happier!! Thank you again"