The Bock Audio 251 is a premier lead microphone for premier voices. It is built to last and provide the studio and user with many years of daily, high end performance.
The Bock Audio model 251 is a high quality variable directivity studio condenser microphone utilizing vacuum tube electronics. Modeled after AKG's classic ela M251, originally built in the 1950's, this mic takes that platform and expands the electronics bandwidth. It utilizes it's own proprietary cable and power supply. The microphone's audio output is standard male XLR3, with positive excitation of the diaphragm at the front of the mic resulting in a positive voltage at the output XLR's pin 2. Audio output is fully transformer balanced.
The Bock Audio 251 uses classic single triode circuitry with no additional negative feedback and high quality through hole components. Through hole components are more mechanically robust than surface mount and allow for worldwide ease of repair. Single triode mic circuits demand excellent capsules before them and excellent transformers after them, with a reward of low noise, simplicity of troubleshooting, and classic sound unachievable otherwise. The Bock 251 departs from the classic 251 of the 1950's in it's expansion of the bandwidth of the electronics, which has had it's low frequency cutoff frequency decreased from 80Hz to 10Hz, without any loss of high frequencies, by use of a larger transformer. As well, the cathode bias cap has been increased to maximize warmth.
It is recommended that the user place the mic in it's shockmount on a stand and connect all the cables before applying power to the unit. Allow a few minutes for the mic to warm up.