Bi-Directional Ribbon Microphone
The R44 from AEA is one of those rare mics that has remained relatively unchanged from its inception, and still sounds great some 75 years later.  Wes Dooley, a specialist in ribbon mics of all kinds, has now restored the 44 type microphone to its rightful position in the studio.  After tracking down the engineers who designed and built the original RCA 44, AEA acquired ribbon material, made the tooling and custom machined all the parts necessary to build the original RCA 44 B/BX design to its original specifications, just as it was in the 1930s.  After years of painstaking work, AEA has again begun production of the most important ribbon mic of all time: the AEA R44C.  Product Features/Specifications: 
An accurate reproduction of the original RCA ribbon mic 
Uses the same ribbon material as the original 
Built to the highest studio standards possible 
A single diaphragm Figure 8 ribbon microphone 
High null-axis rejection 
Custom AEA transformer 
High SPL capability, max level of 140dB plus above 200Hz 
Low self noise 
Consistent polar response 
Operable in high humidity environments 
Sounds equal to or better than the original RCA 44 
Technical Specifications:  
Link  
https://www.aearibbonmics.com/wp-content/uploads/2018/01/AEA-R44-Specifications-2-3-18.pdf  
Operating Principle: Pressure gradient transducer 
Directional Pattern: Bi-directional 
Frequency Range: <20 Hz to >20 kHz 
Polarity: Pin 2 high for positive pressure on front of microphone 
Polar Response: Native bidirectional, figure-of-8 pattern 
Horizontal: Up to 90 dB rejection at right angles to the front/back axis. 
Vertical: Level changes with angle of incidence, but frequency response is consistent. 
Thickness: 1.8 µm 
Width: 0.185 in (4.7 mm) 
Length: 2.35 in (59.7 mm) 
Microphone Dimensions: 
Height: 12.25 in (31.1 cm) 
Width: 4.62 in (11.7 cm) 
Depth: 3.25 in (8.3 cm) 
Weight with cable: 7 lb 9 oz (3.43 kg) 
Connector: XLR-3M 
Maximum SPL: 165+ dB SPL (1% third harmonic > 1 kHz) 
Sensitivity: 2.25 mV/Pa (-53 dBV) into unloaded circuit 
Output Impedance: 270 Ω Broadband 
Recommended Load Impedance: 1.2 KΩ or greater 
Phantom Power: Not required or recommended 
Accessories Included: Vertical case, user manual, captive 10” (3 meter) output cable with XLR-3M connector