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| New Filter Caps For an Epiphone EA-32RVT Gibson amps, and the Epiphone amps made by Gibson in the 50's and 60's often used large paper multi-part capacitors for the power supply filters. These are the brown cylinders between the circuit board on the left and transformers on the right (see figure 1). Exact duplicate replacements are often not available. When suitable authentic looking replacements are not available, it is necessary to they be replaced with more readily available- individual, axial-lead, metal-can, electrolyic capacitors such as Sprague Atoms or Illinois. |


| Figure 1 - Inside the EA-32RVT * BEFORE* replacing the filter caps |
| I've seen many of the Gibson/Epiphone amps that have had the multi-caps replaced using singles, and often there is not a good place to mount a bank of 4-6 singles. Too often I've seen them dangling out in mid-air only supported by their wires or worse yet flopping around on the end of a pig-tail wire that was needed to make the leads reach some obscure connection. The other alternative I'd seen was to band them together and attempt to tie them down where the old multi-caps had been mounted. Then use the leads cut from the old caps to wire into this "bank" of individual caps (this is better than leaving them dangling). Both methods look untidy at best and unsafe at worst. While the original looking paper multi-caps are usually no longer available in suitable values, there are still quite a few metal can multi-caps available. The EA-32RVT originally used two 20-20@450v caps, but even in a metal canister that value wasn't available. Substituting two 32-32@500 multi's like the Marshall amps use was the best alternative. They are still available from many sources. *Note: changing the values from 20uF to 32uF did "stiffen" the power supply up somewhat and seemed to reduce some of the amps tendancy to sound "mushy". How much of this is due to changing the cap's values and how much was due to replacement of the tired old caps is hard to say. At any rate, it worked well, and sounded good. Finding a place to mount the metal cans is not as problematic as trying to mount an entire bank of single caps, and they will probably fit where the old paper caps were mounted in most cases. Pig-tail wires of needed length can be soldered onto the cap's terminals and the connections covered with heat-shrink tubing before installation. Then it's a simple matter of soldering the new pig-tails to the connections that the old paper multi-caps were formerly attached to. Using stick pads and wire ties (both available at most electronic supply stores) to hold the caps down is the easy was to mount them. The end result is a much more tidy and secure job overall (see figure 2). |
| Figure 2 - Inside the EA-32RVT *AFTER* replacing the filter caps |