Recording - February 2014 - 58

PLUG-IN OUTLET
Universal Audio
Fairchild Tube Limiter Collection for UAD-2 and Apollo
By Paul Vnuk Jr.
In the history of compressors, the Big Three are
arguably the Teletronix LA-2A, the Universal Audio
1176, and the Fairchild 670.
The LA-2A and 1176 debuted in the middle and
late 1960s, respectively, and Universal Audio still
makes hardware reissues today. By contrast, the
Fairchild made its debut around 1958 and was discontinued by the time the others came into prominence. Fairchild's pro audio division does not exist
today; original vintage units are rare, expensive, and
highly temperamental (unless you have the right NOS
6383 tubes, which are rare and costly themselves).
Back in 2004, Universal Audio modeled the curves
and characteristics of Ocean Way Recording's "golden
unit" Fairchild, and created the Fairchild 670 plug-in for
the UAD-1 DSP engine platform.
Now, with a decade's worth of advances in modeling
technology, UA has returned to that same Ocean Way
unit and modeled it again, down to the component level,
for the new Fairchild Tube Limiter Collection, to which this
time they have also added the mono Fairchild 660.
Meet the Fairchild
A real Fairchild 670 weighs 65 pounds and takes up
8 rack spaces, with 20 tubes and 14 transformers
behind its faceplate (often but not always anodized-
the 660 modeled by Universal Audio was anodized
but the modeled 670 unit wasn't).
Back in the early 1960s, a new one cost about
$800, or the equivalent of about $6000 today.
Vintage ones now sell for between $35,000 to
$50,000 depending on condition. Even the third-party
spec-for-spec handmade recreations by ADL, Ear and
others will still set you back close to $15,000. This
makes Universal Audio's price of $299 a bargain, as
long as you own a UAD-2 DSP card or enclosure, or
an Apollo DSP engine/audio interface.
Tube compression
Like most vintage compressors from the 1950s and
1960s, the 660/670 is a simple push-pull design with
minimal controls. Unlike the FET-based 1176 and the
optical circuit of the LA-2A, the Fairchild uses tubes not
only as amplifiers but also for its gain reduction. These
tubes are directly in the audio path without a separate
compression circuit. The commonly used term for this,
trademarked by Manley Laboratories, is Variable Mu
or Vari-Mu ("Mu" being a term for gain), but that term
was nowhere to be found in the original Fairchild literature.
The 660 and the 670 are laid out and function similarly, but some of their internal components and design
elements differ, resulting in both responsive and tonal
variation between the units. In the plug-in realm, while
the 660 appears as a mono GUI and the 670 is stereo,
both plug-ins can be used on mono or stereo sources.
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RECORDING February 2014

Specs and controls
Each channel starts with a large VU meter followed by a large Input knob
that goes from ∞ to 0 dB in 2 dB steps on the 660 and -20 to 0 in 1 dB
steps on the 670. Next is a Threshold knob with a variable throw of 0 to
10. The last control is a 6-position Time Constraint knob that adjusts the
preset attack and release times.

Delivery: Web download
Format: UAD-2/Apollo platform; seen by DAW as VST, AU, or RTAS
plug-in, Mac OS X 10.6+ or Windows 7/8
Copy Protection: locked to UAD hardware, license added to user
account
License: single user/UAD
Documentation: PDF user manual available online
Price: $299; $149 for owners of legacy Fairchild plug-in
More from: Universal Audio, www.uaudio.com

http://www.uaudio.com

Recording - February 2014

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