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1962 OPERATORS’ MANUAL

8

CONTROL DESCRIPTION

 

The 1962 comprises two independent audio channels plus a Stereo Mix section, and both
channels may be operated independently or linked for stereo operation. When used in linked
mode, the control-circuitry for both channels responds to the average of the two channel
settings. It helps to avoid confusion if both sets of channel controls have similar, or, as near
as possible, the same settings. Digital output capability is only available if a D62 digital
interface has been fitted.

 

CHANNEL INPUT

Source Select:

This four-position rotary switch selects the audio input source, which can be
Mic, Mic with 48V phantom power, Line or Aux. The Line and Mic inputs are
via rear-panel XLRs while the Aux input jack is located on the front panel. A
red LED shows when the phantom powered mic option has been selected.

Limit

:

The limiter is available for all input selections and, when enabled, will prevent
clipping in situations where the maximum input level cannot be determined
with accuracy. Use of the limiter also makes it possible to run the output
closer the digital peak level (0dB) without the risk of clipping. Note that with
Line input selected the Limit headroom is only 10dB. Large amounts of gain
could exceed this, resulting in distortion.

A status LED indicates that the limit function is active, and if the signal level
is increased to a point where the limiter operates, the GR (Gain Reduction)
LED will illuminate. It is usually acceptable for the GR LED to flash on
occasional signal peaks, but if it lights regularly or almost continuously, it is
invariably best to reduce the input level using the input gain control, and/or
adjusting the EQ and Tube Drive settings. 

For stereo operation, the limiters should either both be active, or, both
bypassed, to prevent an unwanted image shift(s) during limiting.

As with all limiters, excessive amounts of limiting will be audible, but used
carefully, the limiter offers protection against transient clipping while retaining
tonal transparency.

Содержание 1962

Страница 1: ...i 1962 DIGITAL VACUUM TUBE PRE AMP OPERATORS MANUAL...

Страница 2: ...THER ORAL OR WRITTEN EXPRESSED OR IMPLIED THE MANUFACTURER MAKES NO OTHER WARRANTY EITHER EXPRESS OR IMPLIED INCLUDING WITHOUT LIMITATION ANY IMPLIED WARRANTIES OF MERCHANTABILITY FITNESS FOR A PARTIC...

Страница 3: ...ge 8 Limit page 8 Microphone Pre amplifier page 9 Auxiliary Input page 9 Line Input page 10 High and Low Pass Filters page 11 Fine Tune EQ page 11 Enhance page 12 Tube Drive page 13 Stereo Mix page 14...

Страница 4: ...uit different from that to which the receiver is connected Consult the dealer or an experienced radio TV technician for help Unauthorised changes or modification to this system can void the users auth...

Страница 5: ...m x 5mm THE MAINS INPUT FUSE MUST BE RATED AT 250mA WHERE THE MAINS INPUT VOLTAGE SWITCH IS SET TO 230 VOLTS AC AND 500mA WHERE THE MAINS INPUT VOLTAGE IS 115 VOLTS AC CAUTION MAINS CABLE DO NOT ATTEM...

Страница 6: ...extremely low noise balanced input circuitry followed by true high voltage tube amplification enabling modern microphones to take on the characteristics of older tube models Phantom power is individu...

Страница 7: ...l For high quality location recording the 1962 makes the perfect partner for a DAT machine combining the functions of stereo mic preamp with the capability to output high resolution digital data with...

Страница 8: ...onnect the power inlet earth but instead try disconnecting the signal screen on one end of each cable connecting the outputs of the 1962 to the patchbay If such measures are necessary balanced operati...

Страница 9: ...g of multiple 1962s only one need be fitted with a D62 digital converter This option saves on cost and also provides a convenient method of mixing especially where no digital mixing facilities are ava...

Страница 10: ...position The status LED illuminates to confirm this mode has been selected The output socket fully conforms to the EMC standards if the unit is to be used where it may be exposed to high levels of dis...

Страница 11: ...Never disconnect this unit from the mains supply earth If the unit is to be used at a power input voltage which is different to that as supplied the following procedure must be carried out See followi...

Страница 12: ...en enabled will prevent clipping in situations where the maximum input level cannot be determined with accuracy Use of the limiter also makes it possible to run the output closer the digital peak leve...

Страница 13: ...tely 3 bits of digital data If the Peak LED illuminates the gain is too high and should be reduced accordingly Phase Rev Depressing this button inverts the phase of the microphone input signal only No...

Страница 14: ...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 makin...

Страница 15: ...e of interference The High Pass filter is also helpful in reducing the level of the fundamental frequency in mains hum though it will not remove the harmonics that cause mains buzz Low Pass A continua...

Страница 16: ...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 cloc...

Страница 17: ...fed into the Limiter stage to increase This will result in increased limiter activity Tube Drive A continually variable control that regulates the amount of tube colouration Note that even at the cont...

Страница 18: ...ent to use the high quality digital output stage of the 1962 if fitted Channel Pan This control pans positions the channel signal between the left and right stereo outputs When a conventional stereo m...

Страница 19: ...yellow LED is flashing an unrecoverable power brownout glitch has caused the DSP to mute its digital outputs Switch the power Off and On again to restore normal operation REAR PANEL CONTROLS There are...

Страница 20: ...rol is selectable on two internal jumper links See configuration jumpers section on page 19 In all configurations the audio signal to the D62 passes through a Soft clip circuit therefore short transie...

Страница 21: ...the remainder bits For example when using a 16bit multitrack machine to record a stereo 24bit signal tracks 1 2 and 3 or 5 6 and 7 must be selected The third channel sounds like white noise and is us...

Страница 22: ...KHz 10dB A particularly effective setting combining subjective neutrality with a worthwhile increase in dynamic range and high tolerance to post HF EQ 6 Shaped dither above 14KHz 20dB 7 Shaped dither...

Страница 23: ...Channel Output Level control It is less desirable option for the Mix section and the Digital Source Chs channels feed to be made post level control for several reasons 1 Digital output noise will be i...

Страница 24: ...ales invoice and a detailed description of the problem Authorised returns should be prepaid and must be insured All Drawmer products are packaged in specially designed containers for the best adequate...

Страница 25: ...gain 0 01 Line Input at 0dBu 0 025 Mic Input at 0dBu 0 01 D62 specification with LINE input 0dBu all effects disabled CROSSTALK 105dB 0dB gain THD n 1Khz 2dB soft clip 70dB 0dB gain THD n 1Khz 20dB 9...

Страница 26: ...1962 OPERATORS MANUAL 22 BLOCK DIAGRAM...

Страница 27: ...Q CHANNEL OUTPUT LEVEL CHANNEL OUTPUT LEVEL OUTPUT LEVEL DITHER CHAN 1 PAN CHAN 1 PAN SAMPLE RATE WORD LENGTH STEREO STEREO POWER ENHANCE ENHANCE TUBE DRIVE TUBE DRIVE IN IN IN IN IN IN IN IN IN IN LO...

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