The large diaphragm, multi-pattern TELEFUNKEN AR-51 was created to bring the classic circuit of the ELA M 251E into a new, affordable microphone. Built in TELEFUNKEN’s Connecticut facility by hand, the AR-51 features a combination of premium components to yield a vacuum tube microphone system with sonic qualities way outside its price category. Manufactured and tested to TELEFUNKEN‘s strict standards for both quality and consistency, the AR-51 has its own unique distinctions and flexibilities in application that make it an outstanding value.


The amplifier circuit is identical to the ELA M 251E and C12, featuring high fidelity polystyrene film capacitors and a new old stock European-made National 12AT7WA (ECC81) vacuum tube. The “WA” designation is military spec for low noise and low microphonics. This is matched with a German-made Haufe T14/1 transformer also used in the top of the line ELA M 251E.


The AR-51 features a dual membrane, 1” edge-terminated capsule that provides smooth midrange, open top end, and extended low frequency response. These characteristics lend the AR-51 equally to vocal and instrument applications, making it an excellent choice for users who seek a mic with a wider set of possible uses. Both male and female vocals shine with this mic. Sources like acoustic guitars and piano sound full without being muddy or dark. Instruments that require close miking such as strings or horns still sound balanced and natural. The power supply features a 9-position polar pattern selector for added versatility and superior accuracy.


The AR-51 utilizes standardized metalwork to reduce production costs while retaining high quality electronics. Capsules are individually tested by TELEFUNKEN in an anechoic chamber for proper frequency response, and vacuum tubes are burned in for 48 hours and tested for noise and gain prior to installation. The circuit board features wide gold-plated ENIG traces and through hole components. The microphone is entirely hand assembled in TELEFUNKEN’s Connecticut facility, finished in sleek black nickel-plated hardware and a dark gray powder coated body with an antique nickel TELEFUNKEN diamond logo.


Due to its flexibility in application, the AR-51 is an ideal mic to use in matched stereo pairs. Drums, piano, choirs, orchestras, and room miking come through with impressive depth and lush stereo imaging.


Each AR-51 microphone system comes complete with:

M 901 Power supply with pattern selection switch

M 801 25’ Dual-shielded TX7 tube microphone cable

M 701 Elastic shockmount

Wooden microphone box


Available configurations:

AR-51 – Standard configuration

AR-51 HC – Includes a TELEFUNKEN hard shell flight case

AR-51 Stereo Set – Matched stereo pair, premium dual power supply, vintage style flight case

Type Pressure Gradient Condenser
Capsule TK51D - 26.5 mm Edge Terminated Diaphragm
Tube Type National 12AT7WA (NOS)
Transformer Haufe T14/1
Polar Pattern 9-Pattern Variable including Omnidirectional, Cardioid and Bidirectional
Frequency Range 20 Hz - 20 kHz, ± 3 dB
Sensitivity 13 mV/Pa, ± 1 dB
THD at 1kHZ at 1Pa (Amplifier) < 0.2%
Output Impedance 250 ?
Maximum SPL (for 1% THD) 128 dB
S/N Ratio 86 dBA
Self Noise (Amplifier) 8dBA
Dimensions 240 mm L x 46 mm Dia
Weight 769 g
Power Supply M 901 - 7 Pin Female XLR Input, 3 Pin Male XLR Output, Polar Pattern Selector
Cable M 801 - 25 ft Accusound TX-7 Cable, 7 Pin Male & Female XLR's
Wood Box WB01
Flight Case HC01 - Hard Shell Protective Case (not included), FC10S for Stereo Set