Sony C17b

The Sony C17b is a Japanese small diaphragm tube condenser from the early 1960’s. With a diameter of only 15mm, its diaphragm is even smaller than the Altec 21B/D capsules, possibly making it the smallest condenser capsule of any vintage tube-era microphone. The microphone itself is also quite small since it only contains the microphone’s 6DH3 tube which was Sony’s version of the AC701K,  manufactured by Sony to be their proprietary microphone tube. The 6DH3 was also used in Sony’s other non-export tube microphones such as the C57, C107, and C220a, was made in extremely small quantities, and is now truly impossible to find in any condition. Most of the 6DH3 tubes we have come across have become noisy over time so we replace them with a Telefuncken EF732 which sounds exactly right and would be impossible to discern in a blindfold test.. actually you’d be able to pick it out because it’s not noisy.

Since the C17b only has a tube in its body (and possibly a cap and resistor), that means that the rest of the microphone’s circuit lives in the PSU -  just like every other Sony tube mic. This particular C17b is an early version that uses the older CP2 PSU, while most of the other C17b’s we’ve come across use the more common CP3b PSU.

In terms of sonics, the mic sounds quite pleasant with a good amount of body and an extended high end that makes it a very nice choice for acoustic instruments, vocals, guitars and even a snare drum if you’re feeling bold and reckless. Want to hear this mic for yourself? You’re in luck!  You can listen to  an entire song recorded with a Sony C17b without and EQ or processing whatsoever at the audio player below.