Recording - August 2014 - 29

Classic look and classic motor
Using the same body, grille, and stand
mount design as the JRS-34, the Cloud
44-A's black body and silver perforated
grille do bear a passing resemblance to
the RCA 44B of old. However, the Cloud
44-A is actually only about half the RCA
mic's depth, measuring 61/2" tall by 27/8"
wide and just over 13/4" deep. Also, the
44-A does not make use of the old large
yoke system of the RCA models. When
not used with the U1, it can mount directly on a mic stand, thanks to an attached
adjustable pivot mount.
One of the things that made the Sankdesigned RCA BK-11 and the modern
Cloud JRS-34 so special was a rounded
magnet design in the ribbon motor. The
BK-11 had some rounded magnets and
surface areas in the motor, but had nonrounded pole pieces. The JRS-34 extended this idea; in its motor, the sides of the
magnets near the ribbon are also rounded. According to Rodger Cloud, this has
the benefit of deflecting most of the indirect sound waves away from the magnets
and the ribbon.
For the new 44-A, Cloud returns to the
classic motor design found in the old RCA
44A as well as many of the RCA PB
series mics. In this motor design, the magnets/pole pieces have a sharp hard edge
and more surface area. On the one hand

it would be easy to see this as a flawed
design, due to secondary reflections
which would effect EQ and imaging. On
the other hand, if that was truly an issue
that resulted in "bad sound", well, feel
free to throw your vintage RCA 44A mics
in a box and send them to me! It's important to note that this was and is integral to
the vintage ribbon sound that we remember. For better or worse, in the audio
world it's often the sonic imperfections of
old that we long for.
The ribbon element in the Cloud 44-A
is 1.9 inches wide, 2.35 inches long and
1.8 microns thick. It has a 20 Hz to 20
kHz frequency response, a maximum SPL
of over 138 dB, and an output sensitivity
of -25.3 dBV/Pa. Like most ribbon mics,
it has a figure-8 polar pattern.
Another difference between the JRS-34
and the new 44-A is in the microphone's
transformer. The JRS-34 used a transformer with a ratio of 1:35, while the 44A has a ratio of 1:28. While this winding is closer in spec to that of a vintage
44, that means it also has a lower output. However, thanks to the active circuitry in the new 44-A, having this low
level before the head amplifier is a nonissue. You get gobs of clean gain that
will work nicely with any preamp, while
retaining the sonic characteristics of the
older style transformer.

Well, not exactly...
Okay, so I've spent some time explaining how the Cloud 44-A is obviously
inspired and influenced by the RCA ribbon
mics of old. Now it's time to move to the
other side of the aisle and explain why
and how the 44-A is its own beast and not
a clone of the classic RCA design.
First, due to the differences in the dimensions of its grille enclosure, there will be subtle sonic differences between the Cloud 44-A
and old RCA mics. Second, and much more
dramatically, the 44-A has that Cloudlifter
active circuitry on board; as an active ribbon,
it will be both louder and cleaner than most
classic vintage ribbon mics. This has the follow-on effect that the Cloud 44-A is not subject to the wonderful and often unpredictable
world of varied mic preamp impedance,
where finicky classic ribbons can sound brilliant on one preamp and terrible on another.
To some engineers, this freedom from variability will be a strength; to others, the loss of
potential tonal variation is a weakness.
According to Rodger Cloud, this microphone was based on modified versions of
the classic RCA 44A rather than a stock
original, and it's not based on the later
RCA 44BX version either.
So what's involved in the modification in
question? It involves removing all of the internal grilles and metal mesh screening that
surrounds the ribbon element, and then

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Recording - August 2014

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