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Introduction:
After thirty
years of repairing, modifying and rebuilding amplifiers, I
have seen literally thousands of circuits and topologies that
I simply didn’t like. The reason I didn’t like them is that
they introduced unnecessary compromises in reliability, serviceability
or in sound quality… sometimes all three! When I began the
Jupiter Project, I decided this amplifier would contain no
such compromises and it would therefore be the amp I love!
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Applications:
High-End Audio
Systems, Extreme Home Cinema, Studio Control-Room Monitoring, Professional
Cinema.
Physical
Configuration:
Jupiter is built
as two monoblock modules which share only the chassis, control system
and mains connection. Each monoblock module is constructed on a
massive heatsink and may be completely removed / replaced using
a hex key and a flat-blade screwdriver. This allows Jupiter to
be repaired on a next-day-turnaround basis by any authorised dealer.
Jupiter
stands on 4 stainless steel, self-levelling and adjustable feet
with replaceable rubber pads. The feet are fixed into four solid
internal pillars which run from top to bottom with M8 stainless
steel bolts. This means that Jupiter amps can be stacked on top
of each other (up to 6 high) to create high powered arrays. The
feet may also be removed (using a 13mm open-end spanner) and substituted,
if desired, with any accessory spikes which use the common M8 thread
(such as Soundcare Superspikes). A spare M8 threaded hole is also
provided mid-chassis to allow tri-point footing, if preferred.
Electrical
Configuration:
Audio input is
received by a true differential balanced-line stage. A low-noise,
high precision, bipolar error amp feeds a complimentary differential
gain stage which provides voltage drive to the output stage. The
output stage uses hand-selected super-matched quartets of LAPTs
which form a complimentary pair of compound supertransistors with
very high current gain. A short, fast global feedback loop sets
the system gain and provides extremely low output impedance. A
massive high-current power supply stage driven by 3 toroidal transformers
provides floating single-ended supplies (11 in total) for each stage.
Onboard diagnostic circuitry ensures safety and stability.
Inputs:
Line-level inputs:
Gold-plated RCA (unbalanced) and XLR (balanced) connectors.
Outputs:
8 x high-current,
gold-plated, insulated binding posts with banana sockets. These
binding posts are interchangeable with any M9-size third-party type
which allows high grade terminals (such as WBT) to be easily fitted
as an option. Speaker switching is handled by 4 high-power relays
(2 per channel) which immediately isolate the speakers in the event
of a fault condition. Although the output configuration is bi-wire
by default, the speaker relays may also be controlled independently
to provide A / B system selection if required.
Controls:
 Power
is controlled by a front-panel switch and/or by trigger input.

 Mute
is controlled by rear-panel switch or by trigger input.

 Inputs
are selected by rear-panel switch or by trigger input.

 Speakers
A are selected by rear-panel switch or by trigger input.

 Speakers
B are selected by rear-panel switch or by trigger input.
A standard DB-9
connector on the rear panel provides easy access to the trigger
inputs. Pinouts and levels are as follows:-
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Pin
|
Function
|
Level
(all rear-panel switches on – see Note 1)
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1
|
Power
On/Off
|
Apply
+12V to switch on (see Note 2)
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2
|
Operate
(Mute)
|
Apply
+12V to mute
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3
|
RCA
(XLR)
|
Apply
+12V to select XLR input
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4
|
Spkr
A (Off)
|
Apply
+12V to switch A Speakers off
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5
|
Spkr
B (Off)
|
Apply
+12V to switch B Speakers off
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6
|
Trigger
Output
|
+12V
output when amp is on
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7
|
+
Switch
|
+12V
constant output
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8
|
Reserved
|
No
connection
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9
|
Ground
|
Zero
Volts (chassis)
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Note
1: When trigger inputs are not used, the rear panel switches
control their respective functions. When the trigger inputs are
used, each rear panel switch will set its respective input’s default
state and logical sense as follows:-
|
Pin
|
Function
|
Switch
= Off
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Switch
= On
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2
|
Operate
(Mute)
|
+12
= Operate
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+12
= Mute
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3
|
RCA
select (XLR)
|
+12
= RCA
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+12
= XLR
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4
|
Spkr
A (Off)
|
+12
= Spkr A On
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+12
= Spkr A Off
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5
|
Spkr
B (Off)
|
+12
= Spkr B On
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+12
= Spkr B Off
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Note
2: Pin 1 is an edge-detecting input. When the amp is off,
the rising edge of the +12V trigger will switch the amp on. When
the amp is on, the falling edge of the +12V trigger will switch
the amp off. A falling edge will not result in any change if the
amp was already switched off and vice versa. The power switch on
the front panel can override the trigger input in either state.
Protection:
Jupiter incorporates
several levels of protection to prevent any internal or external
fault condition from causing damage to either the amp or other connected
equipment. These protection circuits are unique as they have been
specifically designed to ensure the safety of Jupiter without sonic
compromise. Jupiter’s protection is summarised as follows:-
 Soft
Start…
Prevents large
in-rush currents tripping circuit breakers when switched on from
cold.

 De-thump…
Prevents any
noises resulting from power up/down being heard through the speakers.

 Thermal
Overload…
Detects when
the output devices have reached their upper thermal limit.

 Signal
Overload…
Detects distortion
resulting from the amp being pushed beyond its upper power limit.

 Direct
Current…
Immediately isolates
the speakers if any destructive DC voltage is detected.

 SOAR
Protection…
Seperately monitors
the dissipation in each output device without throttling transients.
Specifications:
| Configuration: |
Single
Chassis, Twin Mono, Solid State, Bipolar |
| Output
Power: |
400
Watts RMS Continuous per channel @ 4 Ohms |
| Inputs: |
Balanced
XLR and Unbalanced RCA, switchable |
| Construction: |
High
rigidity, stackable, load-bearing 'H-form' chassis with
stainless steel, self-levelling, adjustable glides. |
| Dimensions: |
482mm
(W) x 178mm (H) x 360mm (D) |
| Weight: |
45Kg |
| Protection: |
Soft-start,
de-thump, thermal overload, signal overload, direct current,
over dissipation (SOAR) Protection, speaker protection. |
| Warranty: |
5
years, full parts and labour |
| Input
Voltage: |
240Vac
(110Vac available on special order)
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| Compliance: |
ACA
C-Tick Level 2
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| Colour
Options: |
Arctic
Silver, Black,
Champagne Gold, Signature
Blue
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| Availability: |
60
days A.R.O
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| Price: |
AUD$6600.00
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