Crown Micro-Tech 600 Reference Manual page 26

Controls
Power: A front panel rocker switch used to turn the ampli-
fier on and off.
Level: A back panel rotary potentiometer for each chan-
nel used to control the output level.
Stereo/Mono: A three-position back panel switch used to
select Stereo, Bridge-Mono or Parallel-Mono mode.
Sensitivity: A three-position switch inside the back cover
plate used to select the input sensitivity for both channels:
0.775 volts or 1.4 volts for standard 1 kHz power into
8 ohms, or 26 dB gain (see Section 4.4).
Ground Lift: A two-position back panel switch used to
isolate the phone jack input grounds from the AC ground.
Reset ( Micro-Tech 2400 only): A back panel push button
for each channel used to reset the circuit breaker for each
channel.
Indicators
Enable: This amber indicator shows the on/off status of
the low-voltage power supply and cooling fan.
ODEP: These amber indicators show the thermodynamic
energy reserve for each channel. Normally they are brightly
illuminated to show that reserve energy is available. In the
rare event there is no reserve, they will dim in proportion to
ODEP limiting. They remain off if the power is turned off,
disconnected, or if the low-voltage power supply fuse
blows. A channel's ODEP indicator will also remain off if its
high-voltage supply fuse blows (or breaker opens) or if
transformer thermal protection is activated.
Input/Output
Input Connector: Two balanced ¼-inch phone jacks. See
Section 8.2 for XLR and barrier block accessories.
Input Impedance: Nominally 20 K ohms, balanced. Nomi-
nally 10 K ohms, unbalanced.
Input Sensitivity: Settings include 0.775 volts and 1.4 volts
for standard 1 kHz power, or 26 dB gain (see Section 4.4).
Output Connectors: Two sets of color-coded binding
posts for banana plugs, spade lugs or bare wire (Euro-
pean models do not accept banana plugs).
Output Impedance: Less than 10 milliohms in series with
less than 2 microhenries (see Figure 6.9).
DC Output Offset: (Shorted input) ±10 millivolts.
Output Signal
Stereo: Unbalanced, two-channel.
Bridge-Mono: Balanced, single-channel. Channel 1 con-
trols are active; channel 2 should be turned down.
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Micro-Tech 600/1200/2400 Power Amplifiers
Parallel-Mono: Unbalanced, single-channel. Channel 1
controls are active; channel 2 is bypassed.
Protection
Micro-Tech amplifiers are protected against shorted, open
or mismatched loads; overloaded power supplies; exces-
sive temperature, chain destruction phenomena, input over-
load damage and high-frequency blowups. They also
protect loudspeakers from input/output DC and turn-on/
turn-off transients.
If unreasonable operating conditions occur, the patented
ODEP circuitry will proportionally limit the drive level to
protect the output stages, particularly in the case of el-
evated temperature. Transformer overheating will result in
a temporary shutdown of the affected channel; when it has
cooled to a safe temperature, the transformer will auto-
matically reset itself. Controlled slew rate voltage amplifi-
ers prevent RF burnouts, and input overload protection is
provided by the input current limit. Refer to Section 4.3.
Turn On: The four-second turn-on delay prevents danger-
ous turn-on transients. Turn-on occurs at zero crossing of
the AC waveform, so power sequencers are rarely needed
with multiple units. Note: To change the turn-on delay time,
contact Crown's Technical Support Group.
Construction
Steel chassis with durable black finish, front panel Lexan
overlay and specially designed "flow-through" ventilation
from front to side panels.
Cooling: Internal heat sinks with forced-air cooling for
rapid, uniform heat dissipation.
Dimensions: Standard 19 inch (48.3 cm) rack mount width
(EIA RS-310-B), 3.5 inch (8.9 cm) height and 16 inch
(40.6 cm) depth behind the mounting surface.
Approximate Weight: Center of gravity is 6 inches
(15.2 cm) behind the front mounting surface.
120 VAC, 60 Hz Units:
Micro-Tech 600 : 36 pounds, 4 ounces (16.5 kg) net;
41 pounds, 2 ounces (18.7 kg) shipping weight.
Micro-Tech 1200 : 41 pounds, 1 ounce (18.6 kg) net;
45 pounds, 3 ounces (20.5 kg) shipping weight.
Micro-Tech 2400 : 46 pounds, 14 ounces (21.3 kg) net;
55 pounds, 12 ounces (25.3 kg) shipping weight.
International Units:
Micro-Tech 600 : 39 pounds, 7 ounces (17.9 kg) net;
44 pounds, 2 ounces (20.0 kg) shipping weight.
Micro-Tech 1200 : 41 pounds, 0 ounces (18.6 kg) net;
45 pounds, 4 ounces (20.5 kg) shipping weight.
Micro-Tech 2400 : 47 pounds, 9 ounces (21.6 kg) net;
56 pounds, 6 ounces (25.6 kg) shipping weight.