A Perfect example of a period correct U 47 clone
The Wunder Audio CM7 Tube Microphone comes with the original large-style U47 transformer that was used in the earlier U47's, including the legendary "Large Badge" U47. These first couple of hundred U47's are very sought after sonically. The CM7 transformer's larger size and high nickel content achieves better low end rolling off at 20 Hz, identical to the original U47 design, instead of 40 Hz. The smaller 40 Hz transformer that was used in later versions of the U47 was made with the 40 Hz roll-off as a requirement for the IRT (German Broadcasting Network). In modern day recording this capability to capture the low end frequencies is essential.