You have to change the input transformer to some higher ratio. V74a is 1:4, V74 is 1:2 and V72a is 1:8. The latter also has a different feedback, but you can change this inside the V74a too. So fitting it with a tranformer of 1:8 or 1:10 you can convert a V74a to a V72a.
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Converting V74a to mic-pre You have to change the input transfo
Converting V74a to mic-pre
You have to change the input transformer to some higher ratio. V74a is 1:4, V74 is 1:2 and V72a is 1:8. The latter also has a different feedback, but you can change this inside the V74a too. So fitting it with a tranformer of 1:8 or 1:10 you can convert a V74a to a V72a.