CTWO 800 - Audio Amplifier JBSYSTEMS LIGHT - Free user manual and instructions

Product type	Professional audio amplifier
Brand	JBSYSTEMS LIGHT
Model	CTWO 800
Output power (stereo 8 Ω)	2 x 450 W
Output power (stereo 4 Ω)	2 x 780 W
Output power (bridged 8 Ω)	1300 W
Frequency response	10 Hz - 50 kHz (-1.5 dB)
Input sensitivity	0.77 V / 26 dB / 1.4 V (selectable)
Input impedance	20 kΩ (balanced active)
Signal-to-noise ratio	100 dB (A-weighted)
Crosstalk	70 dB (at 1 kHz, 8 Ω)
Damping factor	200 (at 1 kHz, 8 Ω)
Slew rate	40 V/μs
Protection	Short circuit, current limiting, DC fault, fuse, limiter, thermal shutdown, transients, soft start
Cooling	Variable speed fan
Power supply	230 V / 50 Hz
Dimensions (L x D x H)	483 x 430 x 132 mm
Inputs	XLR and 6.35mm jack (balanced/unbalanced)
Outputs	Binding posts and Speakon
Operating modes	Stereo, bridged (mono), parallel
Maintenance	Clean the dust filters with a vacuum cleaner

Frequently Asked Questions - CTWO 800 JBSYSTEMS LIGHT

How to connect the amplifier in bridged mode (Bridge)?

Turn off the amplifier. Connect the input signal only to channel 1 (left). Connect the speaker between the red binding posts: red terminal channel 1 (signal +) and red terminal channel 2 (signal -). The minimum speaker impedance must be 8 ohms. Set the mode selector to Bridge, then turn on the amplifier.

What does the red Clip LED indicator mean?

The Clip LED lights up when the output signal reaches its maximum level, causing distortion. If it lights up briefly, reduce the input level. If it remains on continuously, it indicates a short circuit. Turn off the amplifier and check the connections.

How to select the input sensitivity?

Use the 3-position sensitivity selector: 0.77 V (gain 26 dB), 1.4 V (recommended with JB Systems mixing consoles) or 26 dB. The setting depends on the output level of your preamplifier.

What is the difference between stereo, bridged, and parallel modes?

In stereo mode, each channel operates independently. In bridged (Bridge) mode, both channels are combined for higher power on a single load (mono). In parallel mode, both channels are fed by the same input (left channel) but remain independent at the output.

How to clean the amplifier?

Regularly clean the dust filters located behind the front panel using a vacuum cleaner. Never use water. Avoid obstructing the ventilation holes.

What to do if the yellow protection LED lights up?

The yellow protection LED lights up in case of a fault or if the internal temperature exceeds the limit. Turn off the amplifier, let it cool down, and check the connections. If the problem persists, contact your dealer.

Can I use unbalanced jack cables?

Yes, the Jack inputs accept balanced and unbalanced signals. For an unbalanced signal, use a mono jack: Tip = signal, Sleeve = ground. For a balanced signal, use a stereo jack: Tip = signal +, Ring = signal -, Sleeve = ground.

How to replace the fuse?

Unplug the amplifier. Replace the fuse with a new one of the same type and rating. If the fuse blows again, consult a technician.

What is the purpose of the ground lift switch?

The Lift switch allows disconnecting the ground connection between the amplifier and other devices, which can eliminate ground loops and hum.

What is the power in parallel mode 8 ohms?

In parallel mode, the power is identical to stereo mode. For 8 ohms, each channel delivers 450 W, i.e. 2 x 450 W. The impedance seen by the amplifier is halved if both channels are loaded.

USER MANUAL CTWO 800 JBSYSTEMS LIGHT

The PS series amplifiers are high quality and performance amplifiers. To get the maximum result, it features a servo system, power supply and a fan with adjusted speed.

The main features include:

• XLR and 1 / 4' jack balanced input
• Input sensitivity switch
  Output: Speacon and speaker terminals
• Stereo, bridge and parallel switch
  Soft start
  Perfect protection system for the speakers
• Thermal cut off (85°C protection)
  Current limiter

2. Precautions

• Use an adequate power source.
• Do not turn on several amplifiers at the same time.
• Do not allow that the ventilation holes in the front or in the back of the amplifier are blocked in any way.
• Input level controls are present on each channel.
  Output can use speacon or binding posts.
• Please check carefully if the mode switch is in the correct position: stereo, bridge or parallel.
• Clean the amplifier regularly. Especially the dustfilters located behind the front panel should be cleaned regularly.
• Use a vacuumcleaner to remove dust inside the amplifier. Never use water.
• In case of a defect, contact your dealer.

3. Major Operation Controls

A. Front Panel

1. Power ON/OFF

With this switch, you turn the amplifier on. You will note a brief delay in the switching on, due to the soft start.

2/3. Input Level Control

With these rotary VR's, you can adjust the input level of each side. In bridge or parallel mode, only the left VR is active.

4. Power ON Indicator (green)

Indicates that the amplifier is on.

5. Bridge Mode Indicator (green)

Indicates that the amplifier is working in bridge mode. In this case only the left channel needs an input signal.

6. Parallel Mode Inindicator (green)

Indicates that the amplifier is running in parallel mode. The input signal must only be applied to the left channel.

7/8. Protection LED (yellow)

The led light up when the amplifier is overheated (thermal protection) or when something is wrong with the amplifier.

9/10. Peak Level (clip) Indicator (red)

These led will light up in two situations:

a. When the output signal has reached its maximum level, the LED will light. This goes with a distortion of the audio signal. When this occurs, reduce the input level.
b. When you have an input signal and the clip led lights continuously, it means that you have a short circuit on the output. Please turn of the amplifier and check out the problem on the load.

B. Rear Panel

1/5. 1/4' Jack Input Connectors

You can use a balanced or unbalanced input signal.

• Unbalanced: use a mono jack. Tip=signal, Sleeve=ground.
• Balanced: use a stereo jack. Tip=signal+, Ring=signal-, Sleeve=ground.

2/4. XLR Input Connectors

You can use a balanced or unbalanced input signal.

• Unbalanced: Pin 1=ground, Pin 2=signal, Pin 3=ground=pin 1.
• Balanced: Pin 1=ground, Pin 2=signal+, Pin 3=signal-.

3. Input Sensitivity Switch

The position of this switch is very important and depends on the output level of your preamplifier. There are 3 positions:

Full power output at 0,77V input level
26 dB gain of the input signal
Full power output at 1,4V input level. Use this position with JBSystems mixers.

6. Mode Selector

You can select between stereo mode, bridge mode or parallel mode.

• When you use stereo mode, you have to connect the input and output of both channels.
• When you use bridge mode, the input signal must be applied to the left channel only.
• When you use parallel mode, the input signal must be applied to the left channel only.

7. Ground Lift Switch

Setting this switch to the position "left" breaks the ground loop between the amplifier and the chassis ground of various components.

8/11. Speacon Output

When you work in stereo mode, you can use the speacon for connecting your speakers.

The connections are:

1+ and 2+: signal

1- and 2- : ground

9/10. Binding Posts

In stereo mode:

Red = signal

Black = ground

12. Power Cord Socket and Fuse

When the fuse is broken, replace by the same type and value.

4. Operation in bridge mode and parallel mode

A. Bridge Mode

• Turn the amplifier off
• Connect the input to CH1 (left) only
• Connect your speaker system across the red terminals

Red terminal CH1: signal +
Red terminal CH2: signal - (ground)

• The minimum impedance of your speaker system should be 8 Ohm

• Set the mode switch on BRIDGE

• Turn the amplifier on

B. Parallel Mode

• Turn the amplifier off
• Connect the input to CH1 (left) only
• Connect your speakers in the normal way, as you should do in stereo mode
• Set the mode switch on PARALLEL
• Turn on the amplifier

5. Technical Data

MODEL		C2-450	C2-650	C2-800
Output Power	Stereo 8 Ohm Stereo 4 Ohm Bridge 8 Ohm Parallel 8 Ohm Parallel 4 Ohm	300W + 300W 450W + 450W 800W	400W + 400W 650W + 650W 1000W	450 W + 450W 780W + 780W 1300W
Frequency Response		10Hz-50KHz -1,5dB	10Hz-50KHz -1,5dB	10Hz-50KHz -1,5dB
Input Sensitivity		0,77V/26dB/1,4V	0,77V/26dB/1,4V	0,77V/26dB/1,4V
Maximum Input Level		2 Volt	2 Volt	2 Volt
Input Impedance Active Balanced		20k Ohms	20K Ohms	20K Ohms
S/N Ratio A-Weighted RMS		>90dB	>95dB	>100dB
Crosstalk at rated output power 8 Ohm 1KHz		>70dB	>70dB	>70dB
Damping factor at 1KHz 8 Ohm		>150	>200	>200
Slew Rate Internal		30V/μs	35V/μs	40V/μs
Protection		Short circuit, current limited, DC fault, AC line fuse, thermal cut off, power up/down transients, slow start	Short circuit, current limited, DC fault, AC line fuse, limiter, thermal cut off, power up/down transients, slow start	Short circuit, current limited, DC fault, AC line fuse, limiter, thermal cut off, power up/down transients, slow start
Cooling		Variable Speed Fan
Power Supply		230V-50Hz
Dimensions (mm)		483 x 430 x 132

FRANÇAIS

$$ P i n 3 = m a s a $$

Balanceado : Pin1 = masa

$$ \mathrm {P i n} 2 = \mathrm {s e n a l} + $$

$$ P i n 3 = s e \tilde {n} a l - $$

3. Interruptor de sensibilitad de entrada