Neumann audio/microphone transformers have a high reputation for accuracy and naturalness.
I purchased this pair of Neumann transformers from Europe about 12 years ago. They are dead quiet with excellent frequency response across the spectrum. They have a step-up ratio of 10:1, so are usable with a wide range of low output cartridges. I had my audio technician install them in a nice steel enclosure which is well grounded.
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