Drawmer 1962 Digital Vacuum Tube Pre-Amplifier - Manual (Page 16)

1962 OPERATORS’ MANUAL 12
Low Fine Tune:
Continually variable 6dB per octave shelving filter, providing up to 12dB of cut
or boost. This control may be used to add 'warmth' to the signal being
processed or to moderate excessive low frequency content.
Mid Fine Tune:
Continually variable 6dB per octave bandpass control providing up to 12dB
of cut or boost. The centre frequency of 1KHz has been chosen to emphasise
'bite' or presence.
High Fine Tune:
Continually variable 6dB per octave shelving filter providing up to 12dB of cut
or boost. This control may be used to moderate excessive brightness or to
add a high frequency 'gloss'.
In: When depressed, the push button will place the Fine Tune EQ and the
Channel Insert rear panel Jack in circuit. A red status LED indicates such a
situation. When this section is bypassed, any processor connected via the
insert point will also be bypassed.
The Fine Tune EQ controls (and any external inserted process(es)) come
before the Peak Limiter in the signal side chain. Adding gain either via EQ
boost or by external processing will result in a greater degree of limiting
unless the input gain is reduced.
ENHANCE
The 1962 includes advanced circuitry designed to enhance
transient detail by dynamically controlling the phase and
spectral content of the programme material. The LEDs
above the Enhance controls show the degree of
enhancement taking place, and turning the Enhance control
clockwise increases the amount of processed signal added
back into to the programme material. If the Enhance controls
are rotated fully clockwise and dynamic material is processed, the yellow LEDs will seem
to be illuminated constantly. In reality, dynamic enhancement will still be occurring, but the
peaks may be so close together that the LED will appear to be lit continuously.
The Enhance circuitry comes before the Peak Limiter in the signal side chain.
Although only small amounts of additional level will be generated in normal
use, high settings of the Enhance controls may result in more frequent
Limiting unless the input gain is reduced.
Low Enhance:
The low frequency enhance circuit is a level dependant filter designed to
emphasise low frequency harmonics according to the dynamic nature of the
programme material. At low signal levels, the degree of enhancement is
greater than at higher signal levels, which has the result of increasing the
subjective loudness of the material.
The control is continually variable and is designed to be adjusted so that the
LED above illuminates periodically. If the input signal is near the maximum
operating level (0dB on the input meter) then no low frequency enhance will