Telefunken U48

U48

10 years after the development of the ubiquitous U47, the U48 was released with one variation to the U47; it had “bidirectional” (figure 8) capability. The bidirectional capability can be very useful in more “ambient” recording environments where the engineer recording the sound does not want to hear as much of the room ambience as might be recorded with an omnidirectional or cardioid pick-up pattern.

Sonic Characteristic

According to the book Recording The Beatles, the U48 was one of George Martin’s favorite microphones when actually “recording The Beatles”. Utilizing the same M7 capsule, BV8 output transformer and VF14K vacuum tube as TELEFUNKEN’s historic reissue of the U47, the U48s authoritative mid-range and extended low-end response make the microphone an excellent tool for recording vocals and acoustic instruments, both near and far.

Circuit Design

Since its original development in the late 1950s, the TELEFUNKEN U48 has been the microphone of choice for generations of recording professionals. The original U48 also featured the famous M7 capsule which had been developed in 1928 by Georg Neumann. To this capsule was added an amplifier built from military surplus VF14 tubes (they had been used in field and aircraft radios), and BV8 output transformers. The combination of these components created a sonic quality that was absolutely unheard of in the English speaking world of the mid-1940s when darker sounding, less detailed ribbon microphones were the standard.

Construction

The large, chrome headgrille houses a newly manufactured M7 capsule. Its matte nickel finished body houses a new BV8 output transformer and a newly developed VF14k vacuum tube; a “plug and play” replacement for the rare VF14M tubes found in the original. The classic “TELEFUNKEN” diamond logo proudly adorns the front of the body tube.

Each U48 microphone comes complete with M940 power supply, M840 25’ dual-shielded ACX-7 tube microphone cable, M740 elastic shock mount, FC40 locking flight case and WB40 wooden microphone box.

Type Pressure Gradient Condenser
Tube Type TELEFUNKEN Elektroakustik VF14K
Transformer Custom Wound Telefunken BV8
Polar Pattern Cardioid, Bidirectional
Frequency Range 20 Hz - 20 kHz, ± 3 dB
Sensitivity 24.5 mV/Pa ± 1 dB
THD at 1kHz at 1Pa (Amplifier) <0.3%
Output Impedance 400 Ω
Maximum SPL (for 1% THD) 127 dB
S/N Ratio 85 dBA
Self Noise (Amplifier) 9.5 dBa
Dimensions 240 mm L x 60 mm Dia.
Weight 620 g
Current Draw from Mains 85 mA
Power Supply M 940H PSU - Vintage Compatible 6 Pin Female Tuchel Input, 3 Pin Male XLR Output
Cable M 840H - 25 ft Sommer SC-Square 4-Core Cable, Vintage Compatible 6 Pin Male & Female Tuchel
Shockmount M 740 - Clasping Elastic Mount
Wooden Box WB40
Flight Case FC40 - Vintage Style Locking Combination Flight Case, FC40S for Stereo Set