Universal Audio UAD POWERED PLUG-INS ver.6.1 - Manual (Page 149)

UAD Powered Plug-Ins Manual - 149 - Chapter 12: Ampex ATR-102
Ancillary Noises Tape recorders have inherent signal noises that are a by-product of the elec-
tro-mechanical nature of the machine. While “undesirable” tape system noise
is historically considered a negative and was an attribute that pushed the
technical envelope for better machine design and tape formulas (and ulti-
mately, “noiseless” digital recorders), noise is still an ever-present character-
istic of the sound of using tape and tape machines.
The UAD Ampex ATR-102 models the hum, hiss, wow, flutter, and crosstalk
characteristics of the original hardware. These noise components can be in-
dividually disabled, adjusted, and/or exaggerated for creative purposes
(even though the servo-controlled, direct-drive capstan tape transport of the
original hardware provides excellent wow and flutter specifications).
Modeled
Transformer
The original hardware was manufactured with isolation transformers, which
can color the signal. A common modification to the hardware tape machine
eliminates the transformers from the signal path to produce a (subjectively)
“cleaner” sound. UAD Ampex ATR-102 simulates the behavior of the trans-
formers in the hardware circuit, and can be optionally disabled in the plug-in,
providing both sonic options.
Tape Delay A popular application of multi-head tape recorders is to employ them for slap-
back tape echo effects. If the machine is running in record mode but the re-
corded signal is monitored from the repro head (as opposed to the sync
head), the physical space between these two heads results in a short delay be-
tween the signal sent to the recorder and the monitored signal. When these
signals are combined with mixer routings, the classic slapback echo is mani-
fest. The UAD Ampex ATR-102 implements the ability to reproduce this classic
effect with a simple set of controls, and expands the capabilities by extending
the available delay times beyond what is possible in the physical realm.
Automatic
Calibration
The ability of a magnetic tape recorder, which has inherently non-linear re-
sponse characteristics, to accurately reproduce an audio signal with a mini-
mum of noise and distortion requires precise adjustments to the system elec-
tronics. The calibration settings are based on the current tape speed,
formulation, emphasis EQ, and tape width. The hardware must be meticu-
lously re-adjusted each time a different tape, speed, emphasis EQ, or head
width is used (and for system wear and drift, even if these variables are not
changed). UAD Ampex ATR-102 has an automatic calibration feature that
tunes all calibration electronics with a single button.