Universal Audio Bock 251 – handbuilt multi-pattern large-diaphragm tube condenser microphone, inspired by the iconic Telefunken ELA M 251. Features German-made CK12 capsule and Cinemag transformer for extended low-end response down to 10 Hz and higher SPL than vintage originals. Ideal for vocals and instruments, delivering "golden unit" sound with smooth, open tone. Switchable polar patterns: omnidirectional, cardioid, and figure-8. Powered by external PSU, with robust shock mount and vintage-style case.
The device excels with authentic vintage character, low noise, and precision, hand-tested at UA's Custom Shop in Santa Cruz, California.
MAIN FEATURES
- Handbuilt at UA Custom Shop with premium components
- CK12 capsule and Cinemag transformer for extended LF and higher SPL
- Three polar patterns: omni, cardioid, figure-8
- NOS ECC85 tube for rich harmonic tone
- External true-linear PSU for stable power
- Robust shock mount and vintage-style case
- Ideal for vocals, acoustic instruments, and drums
- Not affiliated with original Telefunken, but faithful inspiration
TECHNICAL SPECIFICATIONS
- Type: Large-diaphragm tube condenser
- Capsule: CK12, 34 mm, gold-sputtered Mylar
- Polar Patterns: Omni, cardioid, figure-8
- Frequency Response: 10 Hz – 18 kHz (±2 dB)
- Sensitivity: Approx. 10 mV/Pa
- Max SPL: 118 dB (1% THD)
- SNR: Approx. 80 dB-A
- Impedance: 200 Ohm (output)
- Power: External PSU, 48V phantom-equivalent
- Connections: XLR
- Dimensions (DxL): 70 x 200 mm
- Weight: Approx. 1 kg (mic)
- Included: PSU, shock mount, case, XLR cable






