AEA A840 Phantom Powered Version Of The Ribbon Mic
The Gold Standard R84
The AEA A840 Phantom Powered Ribbon Mic 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. This avoids noise problems in low signal level applications. Touring musicians 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 AEA A840 Phantom Powered Ribbon Mic 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″ x 0.185″ x 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. 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.
- 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
Applications & Audio
Our experience shows the A840 sounds best on vocals when used at a distance of 6 to 24 inches (15-60 cm). However, you may find that positioning the microphone closer or further away from the singer yields better results depending on the voice, the room or the musical style. When recording at 6 inches (15 cm) or closer, it is advisable to have a pop filter handy. The ribbon is well protected from damaging plosive blasts, but to avoid noises from wind blasts, we recommend using a pop filter.
If you are recording a musician who sings and plays an instrument at the same time, you can make use of the exceptional rejection offered by the 90º “null” planes of the bidirectional pickup pattern to reduce the pickup of the instrument in the vocal microphone.
Brass and Woodwind
The A840 has become one of the top go-to microphones to record brass instruments for engineers and musicians alike. Whether live or in the studio, the A840 is known for capturing the full-bodied sound of brass and woodwind instruments. Soprano saxophone, trumpet, and most high- pitched brass and woodwind instruments are known to have “edgier” or “brilliant” frequency characteristics. The A840’s smooth treble response is great at preserving these frequencies without aggravating the striking tonal qualities.
Depending on the instrument’s dynamic range, we recommend starting by positioning the A840 8 to 16 inches (20-41 cm) away from the source.
Unlike brass instruments, whose sound emanates entirely from the bell, woodwinds produce sound from the entire length of the body of the instrument. When mics are placed favoring the bell, only lowest fundamentals dominate. For a focused sound, use the yoke mount (not the mic stand) to point the microphone on axis so that its pickup encompasses the entire instrument.
If you are concerned about wind blasts, use a pop filter, or position the microphone slightly off axis.
The A840 excels at capturing the richness and full sound of string groups and string soloists. For string soloists, start by positioning the A840 3 to 5 feet (1-2 m) on axis towards the sound hole. To achieve a balanced string group sound, try placing the A840 5-8 feet (2-3 m) away (either in front or above) from the section. Use the A840’s excellent null points to isolate the A840’s pick up from other sources. If you desire more ambiance texture, pull the microphone further away from the source.
A840s in a Blumlein configuration (coincident pair at 90-degree angle) positioned at a distance of 10 to 15 feet (3-5 m) from a string section will capture a deep and wide image.
For bass string instruments that are bowed and plucked, placing the A840 about a foot away (0.3-0.5 m) will give you a very nice and defined low end. The proximity effect of the A840 can be used to your advantage.
Drums and Percussion
Whether as an overhead configuration, or mono drum room, the A840’s extended low end and smooth high end gives your drum sound that thickness, warmth, and detail without unintended harshness. For mono drum room, start by positioning your A840 at head level 9 feet (3 m) in front of the kit. Depending on the size of the room and kit arrangement, you may want to position the A840 further away if you wish to capture more room ambiance.
Another popular technique to record drum overheads is to set up the mics in a Blumlein configuration (coincident pair at 90-degree angle) above the head of the drummer with each mic pointing in a different direction. This will give you a very wide image of the drums that sounds like you are in sitting center stage.
Both of these techniques also work well for recording the sound of the room. The closer the A840s are positioned to the drummer, the more direct sound and less room ambiance will be captured by the mics.
When recording solo acoustic guitar, position the A840 4-8 inches (10-20 cm) from the guitar. Point the microphone at the 12th fret or where the neck meets the body. This placement will capture clear midrange and pick articulation with a balanced low end.
Try rotating the mic to use its excellent horizontal off-axis performance to find the “sweet spot”. The bass response of the A840 is sensitive to the miking distance. Try pulling the microphone away from the guitar in increments of 1 to 2 inches (2-5 cm). Listen to the guitar up close and when you find a spot that sounds good, try putting the A840 there. Let your ears be your guide.
Authentic and Balanced
To capture an authentic and balanced electric guitar tone with your A840, place the mic directly in front of the amp grille. Locate the center of the speaker cone and place the A840 4 to 8 inches (10-20 cm) away from the speaker. Pointing the mic at the center of the cone will deliver a very direct, “in-your-face” sound. This is the spot that will obtain the most high-frequency content. If it sounds too harsh, try moving the microphone slightly off center of the speaker cone. You can also try positioning the A840 at an angle. You will find that small differences in positioning can make huge differences in the sound, so experiment until you find the spots you like. Close up, the A840 is very good at spotlighting a speaker’s unique sounds at various locations.
When using multiple microphones on a guitar cabinet at the same time, it is important to pay attention to the phase relationship between signals. Try positioning the microphones as close to each other as possible. This avoids phase problems caused by sound arriving at the microphones at slightly different path lengths. Listen to the combined signal summed to mono to catch potential comb filtering that could be caused by out-of-phase signals. When recording with the back lobe of the A840, it’s important to invert the polarity on the preamp or DAW.
For a more natural sound that captures the sound of the amp in your room, try moving the microphone back a couple of feet.
The A840 delivers a great sound as a close-up and distant mic on both upright and grand pianos. On a grand piano we have found two positions to be particularly useful:
- Spaced pair of A840s looking at the hammers in the front. You will need to remove the lid of the grand piano. This position will yield a very natural, hi-fi sound. It is common to pull the mics farther out of the piano than you would with a pair of condensers. You can change the amount of natural room reverb by changing the distance between the mics and piano.
- Blumlein pair (coincident pair at 90-degree angle) of A840s positioned on the side of the piano facing the player: one microphone pointing towards the treble side of the piano, and the other microphone facing towards the bass side that can result in a larger than life recording