Recording - October 2017 - 52

AudioTechnica
AT5047

The newest 50 Series mic is a
transformer-based all-rounder
REVIEW BY PAUL VNUK JR.

ast month in our Fast Forward column, we announced
a new addition to Audio Technica's 50 Series of
microphones: the AT5047. The 50 Series debuted
in 2012 with the vocal-focused AT5040 (reviewed May
2013), followed by the smaller instrument-focused AT5045
in 2015 (reviewed in February of that year). When the
Audio-Technica's engineers chose to design the 50 Series,
they approached it with a "sky's the limit" mentality, featuring
cutting-edge circuitry and design principles.

Four sides to the question

Unique to the 50 Series among A-T mics, each model features
a rectangular capsule. The origins of rectangular capsules date
back to the 1950s, to Sweden's Pearl Microphone Labs and later Milab. Both firms still
make rectangular-diaphragm mics today.
The primary benefit of a rectangular diaphragm over a traditional round one is how it
handles resonances. Think of tensioning/tuning
a drumhead; great care has to be taken to get
the tension even all the way around, and even
when properly tuned the drumhead will still exhibit
stray resonances, usually damped by using
physical objects (like a wallet on a snare drum). In
a microphone, the principle is similar and stray
resources are typically controlled electronically
(unless you have a really small wallet).
Now consider how much easier it is to tension
a rectangle evenly from edge to edge. The
end result in a microphone is a better dispersion
of midrange resonant peaks and a more
neutral off-axis response. The smaller-sized
AT5045 features a single rectangular diaphragm
that has almost as much surface area as a
52

RECORDING October 2017

large-diagram capsule, giving it a large mic sound in a
small footprint.
With the AT5040 and now the AT5047, the company took the
rectangular paradigm a step further. The capsule of each model
is made up of four smaller individual rectangular diaphragms
connected in an array to form a larger single diaphragm.
The sonic benefit of combining four rectangular diaphragms
into a single large capsule is best illustrated by a 4 x 10 bass cabinet.
While a cabinet with a single 15" or 18" speaker may give you
more low-end rumble, a cab with four 10" speakers actually
yields more surface area. Also, since each speaker is smaller,
they react faster for a sound that is tighter, clearer and punchier.
In the AT5040 and new AT5047, the combined 2-micron-thick
diaphragms yield almost twice as much surface area as a standard
1" circular diaphragm, and just like speakers, the smaller capsules
react with improved accuracy. This gives the very fast transient
response of a small-diaphragm mic, but in a large-diaphragm mic.
Another benefit: small-diaphragm capsules can be noisy
when pushed hard, but combining four together allows each
capsule to work less hard-so there's a lower noise floor even
with the combined surface area.

The 50 Series transformed

Each mic in the 50 Series uses the latest in permanentlypolarized electret capsule technology. While electrets used to be
shunned as lower-quality designs, they are now used in some
of the most accurate high-end measurement microphones,
like those from Earthworks and DPA.
In that vein, the name of the game with the original AT5040
was hi-fi clarity using matching linear amp circuits, discrete throughhole components, and a very minimal transformer-free circuit
path. The new AT5047 takes a similar approach in electronic
build, but adds in a custom transformer-coupled output. It gives
the mic a richness and weight that adds balance to said clarity.

The AT5047

The AT5047 is very much the AT5040's twin. In addition
to their capsule, they share the same
overall styling and 6.51" x 2.24" high-end
modern aluminum and brass body. The only
visual difference is the sleek monochrome
brushed silver look of the AT5047.
This means the AT5047 also gets to use
the custom AT8480 shockmount originally designed specifically for the AT5040. It is a visually stylized open-front design made from aluminum. The mic is held in place by a locking cradle
system that snaps around the mic and locks with
a set screw; it is packaged with the mic in a
custom molded briefcase, as with the AT5040.
Like the AT5040, the AT5047 is cardioidonly. Specs include frequency response of 20
Hz-20 kHz, open-circuit sensitivity of -29 dB
(35.5 mV) ref: 1V/Pa, impedance of 150 Ω,
maximum SPL of 148 dB (1 kHz/1% THD),
self-noise of 6 dB, typical dynamic range of
142 dB (1 kHz), and signal-to-noise ratio of
88 dB (1 kHz at 1 Pa).

Table of Contents for the Digital Edition of Recording - October 2017