Tag Archives: modification

Marshall JTM-45 Reissue Modification – Part II

In part I of our Marshall JTM-45 transformation process, we installed a point-to-point board from Metropoulos Amplification and began to hear the positive results of our test Marshall as it came to new life.

Now, in Part II of our continued Marshall JTM-45 transformation, we move forward with two additional changes in addition to having the opportunity to compare the final results to an original 1964 badge-logo Marshall JTM-45. The two changes that we decided to perform were to swap out the stock output transformer to a Mercury Magnetics Axiom O45JT-C model as well as to upgrade the board’s capacitors to those made by SoZo Amplification. To say that we were excited as well as just plain curious about the final results, especially when we could now compare it to an original JTM-45— is an understatement.
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Mercury Magnetics Epiphone Valve Junior Mod

The Epiphone Valve Junior is a small 5W amp head that is first most noteworthy because it is, well, cheap. Especially considering it is a tube amplifier, selling for $129 is frankly a bargain. Because of its simplicity and price, it has had a bit of an underground following being a pure-tube circuit with a single 12AX7 in the preamp stage and an EL84 as its output tube running Class A. The amp has 4,8, and 16 ohm output jacks to enable a wide use of cabinets.
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