Grateful, I can't speak to the upgrade on an MA-1. However, I did have this upgrade done to an early production MA-2 MkII to bring it up to current MkIII production status. Ralph replaced the big blue filter capacitors for the power supply with the even larger "built for the MA-2" capacitors and he updated the power supply with the new regulated power supply. There were other updates done to my MA-2 at the same time, so I can't completely isolate the impact of the filter cap and regulated power supply upgrade. Nevertheless, the updated MA-2 clearly had noticeably improved control and authority in the bass, which is what Ralph told me to expect from the larger filter caps. And, the entire amp was smoother and more refined (with lower distortion) throughout the frequency range, which is what Ralph told me to expect from the new regulated power supply. I would expect the update to an MA-1 would have similar results.
If you have not already talked with Ralph about what to expect from this upgrade, I recommend you do so. My experience with Ralph is that he is absolutely straight in his comments about what to expect, and I've always found his description to match what I hear.
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If you have not already talked with Ralph about what to expect from this upgrade, I recommend you do so. My experience with Ralph is that he is absolutely straight in his comments about what to expect, and I've always found his description to match what I hear.
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