Full Text Searchable PDF User Manual
53 Briarwood Road • Florham Park, New Jersey • 07932 • info@sonogyresearch.com • www.sonogyresearch.com
1
Sonogy
TM
"The delicacy of tubes.
The authority of transistors."
Sonogy Black Knight™ Power Amplifier
Owner's Manual
Operation, installation, and
safety
information
serial nos. A9596101 through A9596212
Thank you!
Thank you for purchasing your Sonogy Black Knight
power amplifier. This manual will help you enjoy
your amplifier for many years to come. If you have
any questions about operation or maintenance, please
contact your dealer. Sonogy dealers are true
professionals, and have a wealth of experience with
our products and in designing excellent audio
systems.
A Description of the Black Knight Amplifier
Sonogy amplifiers and preamplifiers offer the
harmonic richness that distinguishes live music from
reproduced music. Often associated with the best in
tube amplifiers, the Black Knight combines natural,
rich harmonics with the traditional virtues of solid-
state circuitry.
Like other truly fine amplifiers, your Black Knight is
designed with
real world
performance in mind rather
than incomplete and artificial specifications. As a
result, the Black Knight is very powerful, and drives
even difficult loudspeaker loads with ease. Output is
37 volts r.m.s. per channel, and the generous power
supplies provide sufficient drive current to handle
demanding speaker loads. More importantly, the
Black Knight/500 is unconditionally stable into
capacitive, inductive and other dynamic loads.
The Black Knight can be used either as a 175W stereo
amplifier or in pairs as 500W balanced monoblocks.
No modifications are necessary to use a Black Knight
as a balanced monoblock; you need only have two
amplifiers and a balanced preamp output to drive each.
If your preamplifier does not offer balanced outputs,
Sonogy offers the Duette™ balancing module, which
creates balanced outputs from unbalanced ones.
Set-Up and Electrical Connections
Your Black Knight should be located on a solid
platform, or on the floor, where it receives good
ventilation and is away from flammable items, such as
curtains or paper.
Connections are required for speakers, preamp input(s),
and for 117VAC or 230VAC power. These are clearly
marked on the rear panel of your Black Knight. All
signal connections should be made with the amplifier
off, to prevent possible speaker damage. If the
amplifier is left on while preamp connections are made,
it could amplify the resulting transient and damage
your speakers.
Two pairs of 5-way binding posts are provided for
speaker connections. These will accept bare wires,
standard banana plugs, or spade lugs. A good
clean
connection is important for consistently good sound.
Clean any connectors used, and insure that all
connections are tight. Do not allow the "hot" and
ground connections to short together. If spade lugs are
used, you may wish to
lightly
tighten the binding posts
with a socket or nut driver; be sure not to crack the
plastic binding post or strip the soft brass threads (we
use a high copper alloy for best sound). If you are
interested in maintaining absolute phase, your Black
Knight does not invert phase. Please note that
connections are made differently for stereo vs.
monoblock operation.
Balanced and unbalanced inputs are provided for both
left and right channels. In addition, a single XLR jack
is provided to drive your Sonogy amplifier as a fully-
balanced monoblock. Balanced monoblock operation
requires two amplifiers for stereo.
Finally, a single IEC modular power jack and line cord
is provided. The 15A power cord provided is suitable
for all applications.
53 Briarwood Road • Florham Park, New Jersey • 07932 • info@sonogyresearch.com • www.sonogyresearch.com
2
Dual-Mono Balanced Operation
Two standard Black Knights may be operated, without
modification, as 500W balanced monoblocks. Each
balanced monoblock (one per channel) must be driven
by a preamplifier with balanced outputs, or by Sonogy's
Duette Balancing Module. If you connect your Black
Knight as a balanced monoblock, be sure to connect the
speaker across the left and right red ("hot") binding
posts. Ground is not used to carry signal in a balanced
configuration. Your authorized Sonogy dealer can
explain fully how to connect a balanced preamplifier to
a pair of Black Knight monoblocks.
Balanced monoblock operation offers many sonic and
technical advantages. Most obviously, this guarantees
the power to reproduce high volume and explosive
dynamics with a greater sense of realism. Many subtle
advantages are offered as well. True dual mono
operation generally enhances the three dimensional
stereo image. Furthermore, balanced operation has
technical advantages, derived from distributing the
speaker's load evenly within the amplifier, which result
in better fidelity, depth of image, smoothness, and
realism, even at lower levels which might not appear to
need the awesome power of two 500 watt monoblock
amplifiers.
Warm-Up
Contrary
to
popular
belief,
even
solid-state
(transistorized) equipment benefits from a warm-up
period. While your Black Knight will operate properly
and safely as soon as it is turned on, most listeners find
that the sound improves substantially during 20-30
minutes of use, and continues to improve over the next
few hours of continual operation.
NOTE: Your Black
Knight will not sound its best until it has been in
standby mode (see below) for at least 24 hours.
Break-in
New amplifiers break-in over a period of 1-2 weeks.
The tonal balance and smoothness will improve.
Standby Mode
Most of this amplifier's low-power circuitry is not
switched on and off. Once your Black Knight is
plugged in, these circuits operate in standby mode. The
Black Knight will not perform optimally until these
circuits have warmed up for at least 24 hours with the
Black Knight plugged into a live AC outlet. Standby
mode is indicated by the front-panel Amber LED.
CAUTION!!! Wait before turning on . . .
When the Black Knight is first plugged in (or
subsequently plugged in after moving), always be sure
that the power switch is off, and wait 2 minutes for the
bias circuits to stabilize. This will avoid an unusual
turn-on surge, blown fuses, and unnecessary strain on
the amplifier.
Ventilation and Heat
Your Black Knight is expected to run warm, but not
hot. Since the Black Knight relies on convection
cooling, it is important to allow space around the
amplifier and particularly important not to obstruct the
cooling fins. Do not stack a preamplifier or any other
equipment directly above the Black Knight. Leave at
least 6 inches of space on all sides, as well as a
dissipation path for warm air. If possible, raise the
amplifier off any rugs by 1-3" to improve airflow and
cooling.
Do not enclose in a cabinet.
Never operate
the Black Knight in such a way that its heatsinks
become hot to the touch.
On/Off Switch
The On/Off switch controls only the high-current
output stages. The rest of the circuitry is in standby
mode whenever your Black Knight is plugged in. The
amp is "ON" when the switch is flipped up, and OFF
when down. The green LED indicates that the Black
Knight is fully "on".
Grounding Switch
On the bottom of the amplifier (rear panel on some
models) is a toggle switch which options the Black
Knight between two grounding configurations. This
switch can eliminate ground loops and noise in
different systems. Choose the position that provides
the lowest hum and buzz. One position should be
clearly superior to the other.
High Output Current:
The Black Knight is a very high current design, capable
of driving low impedance and reactive loads while
maintaining sonic purity. Each channel's output stage
can deliver peak current of 40 amperes (<100mS) and
the Black Knight can deliver 800 watt peaks (<100mS)
without strain.
A high current option, which increases the constant-
current capability into low-impedance loads is available
at additional cost. This option does not increase peak
current nor does it make the Black Knight more stable.
For the vast majority of applications we do not feel that
this option is necessary.
53 Briarwood Road • Florham Park, New Jersey • 07932 • info@sonogyresearch.com • www.sonogyresearch.com
3
D.C. Offset
Your Black Knight is equipped with circuitry which
monitors the presence of DC voltage at the output. A
DC servo constantly adjusts amplifier operation for low
DC at the speaker terminals. If you notice any unusual
operation, or measure more than 100mV of DC at the
outputs, turn your Black Knight off immediately and
contact your dealer for service.
Power Requirements
For safety reasons, the Black Knight
must
be plugged
into a
3-prong grounded
110/120 volt (AC) outlet
1
.
While on, the amplifier may be expected to draw 150-
200 watts at all times, and up to 600 watts
momentarily, and therefore should be plugged directly
into a wall outlet rated for at least 10A
2
. If you have
an unusual requirement, contact your dealer or a
qualified electrician.
Fuses
The high power output stage power supplies and lower
power standby circuitry power supplies are fused
independently. The output stage of all 117V (USA)
models is fused with a 3A slo-blo type fuse (located on
the back panel)
3
. The circuit cards are fused with a 1/4
A slo-blo type fuse inside the amplifier.
Always unplug
the amplifier before attempting to replace an internal
fuse!
Never replace a fuse with one of higher value as
serious damage could occur in the case of failure!!
No
fuses are in the audio path.
Maintenance
Your Black Knight requires no regular electrical
maintenance, and in any event service should be
performed only by Sonogy, Ltd.
Limited Warranty
For warranty information, please see your dealer or
refer to the enclosed warranty form.
Repairs
All repairs must be performed by Sonogy, Ltd or an
authorized service provider. Service or modifications
performed by any other person or establishment will
automatically void your warranty.
Thank You!
Thank you again for your confidence in Sonogy, Ltd.
1
230V/50Hz and 100V/50-60Hz models also available.
2
For 230V operation, the circuit should be 5A minimum.
3
230V models are fused with a 2A slow-blow fuse.
Sonogy, Cantata, Duette, and Black Knight are trademarks of
Sonogy, Ltd.
If you have any suggestions that might improve our
products or our service, or if we may assist you in any
way, please do not hesitate to call or write us at the
address below. Happy listening from the entire staff!
Technical Specifications:
Voltage Output:
37.0 Volts
74.0 Volts mono
Current Capability:
40A peak (<100mSec)
10A continuous
Stereo Power
175 W/ch (8
Ω
)
Monoblock Power
500 watts (8
Ω
)
Active Devices:
Junction FETS,
Bipolar Transistors
Input impedance:
30k-
Ω
unbalanced
60k-
Ω
balanced
Output impedance:
< .3
Ω
Sensitivity:
1.6V (175 W / 37V)
60 mV (1 watt)
Gain:
26dB
Phase Inversion:
no
Shipping Weight:
50 lbs./ 23 Kg
Dimensions:
6.25" x 18" x21"
Feedback:
0 dB (no feedback loops)
Power Consump.:
175W continuous idle
600W maximum draw
SMPTE I.M.:
<.1%
DC Offset:
<10mV
Freq. Response:
5Hz-20kHz +/- <0.25dB
Class of Operation:
very high bias A/AB
Gain stage :
pure class A
AC Coupled:
Yes
Fuses (110V-120V models):
internal
1/4A slo-blow/250VAC
external
3A slo-blow/250VAC
Fuses (220-230V models):
internal
1/8A slo-blow/250VAC
external
2A slo-blow/250VAC
Heat dissipation
175 watts at idle