Active series MicsA840
microphones Active Series

A840

Phantom-powered version of the R84 ribbon mic
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  • Phantom powered R84 with 12 dB more sensitivity
  • Custom German toroidal transformer and JFET electronics
  • Optimal for soft sound sources and classical recording
  • Same award-winning sound as the passive R84
"Almost any ribbon mic will provide the general ‘ribbon’ flavor, but I haven't found one that sounds as well-balanced and useful as this one."

Adam Kagan, Tape Op

The Gold Standard R84

The A840 delivers the same award-winning sound as its passive sibling, the R84. Its higher output and immunity to impedance-loading offer more flexibility in the choice of preamps, and avoid noise problems in low signal level applications. Touring musicians who are looking for consistent and risk-free performance in a wide range of venues and recording setups will find a trusty companion in the A840 microphone. The A840 remedies most of the limitations of passive ribbon microphones, whether in a remote recording situation with long cable runs, a classical music application, or simply for the wish to combine the ribbon sound with a low-gain vintage preamp. The signal strength and flexibility of active JFET electronics combined with the luxurious warmth of a Big Ribbon™ all wrapped up in an affordable package is what sets this microphone apart. No studio is complete without a pair of A840s.

Classic Sound Meets Cutting Edge Technology

Building on the success of the R84 and the legacy of the RCA designs, the A840 marks the next step in incorporating the same modern JFET electronics and high performance transformer as used in AEA’s flagship active microphone, the A440. Back in the RCA days, ribbon microphones were always passive transducers. With the invention of transistors and the subsequent reduction in size of electronic components, it has become possible to use ribbon mics in even more applications. A passive ribbon microphone needs to be matched with a high gain, high impedance preamp, like AEA’s TRP or RPQ, to achieve its best performance. Phantom-powered, or active, ribbon microphones like the A840 can be used with a wider range of preamps, including those commonly found in USB or Firewire audio interfaces. Does this mean that passive ribbons are an obsolete relic of the past? Absolutely not: Passive ribbon microphones still have an edge when it comes to maximum signal level (165 dBSPL instead of 134 dBSPL), the more minimalist signal path, and lower cost.

A Big Ribbon for a Big Sound

The AEA A840 uses a big, 2.35" by 0.185" by 2 micron pure aluminum low-tension ribbon element just like the classic R44. Many ribbon mic manufacturers choose shorter ribbons that are easier to install, but AEA’s Large Ribbon Geometry TM design offers important advantages. Ribbon microphones operate linearly above their resonant frequency, unlike condenser or moving-coil transducers, so the resonant frequency of a good microphone design should be as low as possible. The longer the ribbon, the lower the resonant frequency will be. The ribbon has to move twice as far for every drop in octave as it vibrates within the magnetic gap, thus a longer ribbon will allow for further movement back and forth. This results in the ribbon handling louder sound sources and more sound pressure level (SPL). Most AEA ribbons are tuned to 16.5 Hz, and because the A840 shares the same Big Ribbon™ as the rest of AEA's product line, you will achieve a sound that is smooth, natural and free from any of the uncomfortable resonances that shorter ribbons and condensers can exhibit. The result is a sound that many engineers say is astonishingly close to what their ears hear when you're actually standing in the studio.