Packburn 325 Owner's Manual - page 6
Audio Noise Suppressor Model 325 Technical Specifications
Designed for professional installations and for quality home
sound systems
Outfitted to interface with 600 ohm balanced line systems or with the more customary single-ended Hi Fi systems;
Provided with XLR professional connectors as well as with RCA-type phono connectors for all signal input and
output terminations.
Power Line Voltages:
U.S./ Canadian 105 volts 120 volts, 50/60 Hz
International: 210 volts-240 volts, 50/60 Hz (consult factory)
Power Consumption: 20 Watts
Size:
Width: 19" (483 mm) for rack mount, 17” (432 mm) with mounting ears removed
Depth: 13" (332 mm), Height: 3.5" (89 mm).
Inputs and Outputs:
There are two separate electronically balanced input channels. Separation throughout the
audio frequency range is maintained in processing stereo signals, in which each signal path
is provided with a Blanker, a Treble Equalization network and a Continuous Noise
Suppressor and then routed through a dual OUTPUT LEVEL control to the separate output
terminations.
In processing lateral-cut or vertical-cut recordings, the signals applied to the two input
channels are routed through a balancing circuit to the Switcher. Or, at the operator's choice,
with lateral-cut records, the signal of either channel may be individually selected for
processing. To reduce the audibility of low frequency disturbances, the bass portion of the
two input channels, is mixed in the proper polarity. The output of the Switcher is connected
to both of the Blanker + Equalizer + Continuous Noise Suppressor channels, and the fully
processed signal may be taken from either or both of the output channels.
Electronically balanced input. Single-ended input impedance is 100k ohms.
Electronically balanced output. Single-ended output impedance is less than 1 ohm.
Sensitivity:
With INPUT LEVEL control all the way up, a 0 VU (1.23 v.) reading of the processing
level meters will be achieved by an input signal of — 6 VU or less from a 600 ohms line or
by 0.4 v. or less from a single-ended source. Range of control of INPUT LEVEL
potentiometer is 20 db.
With OUTPUT LEVEL control all the way up, there is unity gain from the metering circuit to
the output terminations.
Frequency Response: Bass response is within ± 1/
2
db to 10 Hz.
Treble response is determined by the setting of the Treble Equalization switch and the
action of the Continuous Noise Suppressor.
Treble Equalization:
is provided by the Audio Noise Suppressor by means of a six-position selector switch which
enables you to match the treble portion of published equalization curves of records, old and
new. Includes FLAT, FFRR, AES, RIM, LP.
Continuous Noise
The Continuous Noise Suppressor is a low pass filter. Cutoff frequency varies from 2.5 kHz to 18 kHz
Suppressor Action:
in accordance with the dynamics of the program material and the nature of the surface noise.
Alternatively, a fixed cutoff frequency may be selected. Meter on front panel reads the cutoff
frequency. Filter has a slope approaching 12 db per octave.
IM Distortion:
60 Hz and 7 kHz, 4:1 at + 4 vu (1.23v.) input: Less than .05%
S/N Ratio:
(Unweighted) – At least 75 dB with reference to + 12 vu (3 v.).
Warranty:
A full five year’s warranty on both parts and labor.
About your Record
To take advantage of the Switching process, you must have equipment to play back discs or
Playback Equipment:
cylinders stereophonically. The two channels of reproduction must be closely matched in
frequency response.
Demonstration CD: Available on request
electronics inc. P.O. Box 226 Syracuse, NY 13215 U.S.A.
Ph 315-476-9121
Covered by one or more of the following US patents: 4,151,471; 4,155,041; 4,259,742; 4,322,641; 7,035,417