Drawmer 1962 Digital Vacuum Tube Pre-Amplifier - Manual (Page 14)

1962 OPERATORS’ MANUAL 10
Gain:
When depressed, provides an additional 20dB of gain to the auxiliary input.
A Yellow status LED will illuminate.
Bright:
Switches in a 'presence' peak of around 10dB at 2KHz to simulate the voicing
of a typical guitar amplifier. Because nearly all guitar amplifiers are voiced
differently, it is likely that additional EQ will be required to achieve the desired
sound.
Input Gain:
When the Input Select switch is set to AUX, the Input Gain control is fully
variable over the range -25dB to +15dB; the gain setting may be read off
using the yellow coloured graticule around the Gain control. The input level
meter must be monitored while adjusting the input gain so that average
programme level is between -18dBfs and -12dBfs while the highest peak
signal level never exceeds 0dBfs. This will permit a programme headroom
of about 18dB (or approximately 3 bits of digital data). If the Peak LED
illuminates, the gain is too high and should be reduced accordingly.
LINE PRE-AMPLIFIER
The line input stage is based around an advanced, discrete component design,
characterised by extremely low levels of noise and distortion. The performance is
significantly better than what is normally achieved by the input stage of a typical, high
quality recording console. When the tube and EQ sections are out of circuit, the line preamp
provides a high quality, minimum signal path to the output, making it ideal for direct
connection to a tape machine or, if the D62 digital interface is installed, to the digital input
of a digital multitrack recorder, DAT machine or hard disk recorder. The tube and EQ stages
may be switched into circuit for applications where it is desirable to 'enhance' the signal
prior to recording.
Input Gain:
When the Input Select switch is set to LINE, the Input Gain control is fully
variable over the range -25dB (attenuation) to +15dB; the gain setting may
be read off using the yellow coloured graticule around the Gain control. The
input level meter must be monitored while adjusting the input gain so that
average programme level is between -18dBfs and -12dBfs while the highest
peak signal level never exceeds 0dBfs. This will permit a programme
headroom of about 18dB (or approximately 3 bits of digital data). If the Peak
LED illuminates, the gain is too high and should be reduced accordingly.
If using the Limiter with Line input selected, caution must be observed when
large amounts of line input gain are used in conjunction with very high line
input levels. It is feasible that the Line Limit headroom of 10dB could be
exceeded in these conditions resulting in distortion.