UAD Powered Plug-Ins Manual
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Chapter 55: Studer A800
Equaliser
(Emphasis EQ)
The Equaliser buttons determine the active Emphasis EQ val-
ues and the frequency of the hum noise. Click the equaliser
buttons to alternate between the two different types.
NAB or CCIR curves can be selected when the Tape Speed is
7.5 or 15 IPS. When the Tape Speed is 30 IPS, neither value
is available (the LEDs are dimmed) because the EQ is fixed with the AES em-
phasis curve.
When the value is set to NAB, the Hum Noise frequency is 60 Hz (the United
States standard). When set to CCIR, the Hum Noise frequency is 50 Hz (the
standard in Europe and other regions). See
“Noise Enable” on page 550
and
“Hum Noise” on page 555
for more information about Hum.
Note:
When
IPS (Tape Speed)
is set to 30 IPS, the yellow LEDs are not illu-
minated, indicating that the Emphasis EQ is set to AES. However, in 30 IPS
mode, the Equaliser switch can still be changed to set the frequency of Hum
Noise.
Tape Speed and Emphasis EQ were originally practical controls for record
duration vs. noise and local standards. It is important to note that historically,
the origin of the tape machine (US or European) dictated the built-in EQ em-
phasis, but later machines like the A800 had both circuits available.
While the hardware A800 has discrete controls for tape speed and emphasis
EQ, the user has to recalibrate the machine for various speeds and re-jumper
the whole machine for 30/15 or 15/7.5 IPS usage. The A800 plug-in has
three speeds and related EQ pre-emphasis/de-emphasis filtering, presented
as two easy to use controls for simple auditioning of the sonic variations.
CCIR (also known as IEC) is the EQ pre-emphasis made famous on British
records and is considered the technically superior EQ; many say this EQ was
part of the “British sound” during tape’s heyday. NAB (also referred to as
IEC2) was the American standard with its own sound. AES is truly standard-
ized for 30 IPS and is the sole EQ found on the Studer A800 for 30 IPS.
Noise Enable
The Noise Enable buttons are a global enable/disable control
for the individual hum and hiss components of the A800 model.
The amount of hum and hiss noises are continuously variable
and are set with the
Hum Noise
and
Hiss Noise
controls
(
page 554
). Click the Noise buttons to alternate between OFF
and ON.
