This kit is for ONLY the Sunfire True Subwoofer EQ model.  It will not work with other models. If you have an HRS or Dominator series, look for listing # 336282077989.  If you have an original True Subwoofer, Signature, MK II, MK IV or Architectural, look for item # 236350385203. If you own a Sunfire True Subwoofer Junior or Super Junior, look for item # 236349782513.
This kit's purpose is to provide capacitors to address a common issue with Sunfire Subwoofer amplifiers after several years--hum. I have not worked on the EQ model myself, but this kit is being developed in response to requests by EQ owners for a kit. 

Four 1000 uF capacitors in the power supply are vulnerable and are replaced with upgraded Panasonic low-ESR versions (C1A, C65, C148, and C170). This may be all that is required to address a hum. Not as likely to fail and not as easy to replace are two 47 uF high voltage capacitors (C39 and C73), but upgrade replacements for them are included. On that same board two 470 uF capacitors can be replaced (C41, C62). On a daughterboard two 220 uF capacitors may be replaced/upgraded (C143).

Sunfire carried over use of some vulnerable capacitors from the earlier True series to the EQ, and have included upgraded Panasonic low-ESR type FR capacitors to replace them. Typically I also increase the voltage rating, where practical.

In response to buyers' suggestions, this kit now offers the option to include a new pair of 200V 1500 uF Nichicon replacement capacitors.  These are from the very high quality LGW series, which is noted for long life, high temperature and handling high ripple current: "Withstanding 3000 hours application of rated ripple current at 105°C." The capacitors are rated for 5.22 A ripple current. They are also more compact, allowing the amplifier to be remounted more easily. The factory originals stand taller. The LGW series has a small tariff cost with it.  A buyer has asked about substituting a 2200 uF 200V Nichicon, which I can do upon request (LLS series; excellent ripple current rating; 85 deg. C., same height as the original capacitors).

As buyers share results and suggestions how to improve this kit, I will modify this listing to provide more help, photos, identification numbers and possibly more components.

Four cautions:

1). Most importantly, observe proper safety precautions. These amplifiers store dangerous voltages in two 200 volt capacitors and in circuits connected to them, even after the amplifier has been unplugged for days. Handling circuits that can still hold high voltage is not something a novice should attempt. I always discharge those capacitors through a resistor before beginning work.

2) While these capacitors address a problem so common that I would address it automatically with every one of these amplifiers as a starting point, there could be additional problems beyond what this kit addresses. Using this kit does not assure that your amplifier will be repaired. 

3) Desoldering and soldering is required for installation.  Be careful not to press on the copper trace or pad when desoldering, nor overheat it, or it may lift. If that happens, note where the trace on the top side of the board connects, so that you can be sure you have correct continuity with the new component.  Using a jumper may be necessary. Double-check your work.

4)  Be sure to observe correct polarity with the diodes and capacitors.  Each component needs to be oriented facing the correct direction (+ and -).  Condition is "New".

A Tip on Large Capacitor Replacement:

First discharge any electrical charge.

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.


Anecdotal Report:

Individual reports are no guarantees of universal results, but with electronics if numerous examples see the same problems and solutions, cumulative results become very useful.  In May 2024 a True Subwoofer EQ owner, to whom I recommended replacing four 1000 uF capacitors (which are included in this kit), reported, "I did replace the 4 capasitors [sic] and all the hum was gone! No other replacement was needed."