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.
The BOCK 251 provides the user with absolute confidence that this is the mic you put in the most critical situations. The BOCK 251 uses a proprietary hand made German capsule, a proprietary hand wound multi sectioned audio transformer, a NOS tube in the mic amplifier, a hand built outboard power supply and a custom low capacitance audio cable. This is one of the best overall mic packages available on the market at any price.
The BOCK 251 is the ideal microphone to choose when there is a variety of applications that must met with absolute top recording quality. With frequency response that extends well beyond the normal range of typical studio microphones, the BOCK 251 sets new standards.
For vocals, the BOCK 251 instantly delivers that huge vocal sound you have wanted for years. It sounds equally impressive on females and males. It will capture the most intimate and subtle details of a vocal yet maintain integrity at high SPL's. It holds up track after track, "sitting on top" in extremely dense mixes without EQ.
For instruments, the BOCK 251 offers very high end performance on critical stringed instruments, orchestras, choirs and small ensembles. The outstanding transient response reveals elusive harmonic details that spell the difference between good and great in your recordings.
Patterns: Cardioid, omni, Figure of 8 Switchable from mic Frequency Range: 10Hz to 18kHz, +/-2dB Sensitivity: 19mv/Pa Equivalent Noise: 18dB ("A" weighted) 32dB (unweighted) Distortion vs.SPL @1kHz:
112dB = 0.5% THD
118dB = 1% THD
129dB = 2% THD Impedance: 200 Ohms true transformer balanced Recommended load: 1.2k Ohms Dynamic range (maxSPL-"A"noise): 94dB S/N (94dB-noise): 76dB "A", 62dB unweighted Capsule size: 1" diameter, dual asymmetrical backplate CK12 type Tube type: New Old Stock 6201 Dimensions: 2" dia x 8.5" oal (52x216mm) Weight: 1lb 9.3oz (1.58lbs) =716g Shipping weight: 12 lbs Power Supply: P251 true linear, factory wired 115v or 230v operation