700 Watt Power Amplifier


The feature-packed SR series of power amplifiers is versatile, rugged and time-tested. The Asystems SR707 power amplifier is specifically designed with the needs of sound contractors in mind. Output is selectable between low-impedance, or 25V, 70V and 100V Line operation, dependent on wiring. Looking to expand your system? An XLR thru output is also available on each channel for line-level signals to additional amplifiers. Each amplifier channel has a separate toroidal secondary transformer that provides full electrical isolation and ensures maximum audio separation. Features like power up muting, full short-circuit, temperature, DC offset protection and a built-in 45 Hz subsonic filter help make the SR series an attractive, attractive solution for any audio installation.

Versatile operating modes

The SR707 power amplifier has a variety of different operating modes that can be utilized depending on your needs. Stereo mode is just simple, regular operation where channels 1 and 2 are sent to their respective outputs. Parallel mode allows a single input to be utilized for both output channels. Bridge mode, on the other hand, will combine the output power of both channels to a single channel to get more output power from the SR707.

Low-impedance operation (2 ohms)

Unlike many amplifiers on the market today, the SR707 can run into impedances as low as 2 ohms. This is perfect for splitting power between up to four 8 ohm speakers, or as many as eight 16 ohm speakers! This phenomenal aspect of the SR707 helps make it one of the most versatile amplifiers on the market.

Operate as a constant-voltage amplifier

The advantage of 70V or 100V constant-voltage output is the ability to string numerous speakers together in large facilities without having to design complex parallel connection schemes. Not only does continuous voltage allow the use of smaller gauge cable (which is easier to run and less expensive), these systems are easily expanded. Continuous voltage systems also allow easy remote volume adjustment, wherein a passive volume control can be installed to provide level control over a single speaker or a multiple-speaker zone.

Thru outputs for expanded operation

Each of the input channels of the SR707 features a direct "through" output which can be connected to additional amplifiers. This allows for virtually limitless expansion of your audio system without the need for any additional output channels on your original input source!

  • Output power: 2 x 350W at 4 ohms, 70V or 100V
  • Low impedance output (2 ohms): 550W per channel
  • Stereo, bridge or parallel operation modes selectable via rear mounted switch
  • XLR and barrier strip input connectors
  • Line-level XLR ‘thru’ output connectors
  • Output via covered barrier strips
  • Wide range of protection circuitry and rumble/electrical filters for complete peace of mind
  • Toroidal output transformers provide full electrical isolation and meet worldwide safety standards
  • Rack mountable design taking up 3 standard rack spaces (19″ rack)
  • Automatic dual-speed, high-efficiency cooling fan


Front Panel

Asystems designers kept the front of the SR703 simple: both channels feature protect, limit and signal LEDS which are yellow, red and green, respectively. In addition to this, a front-panel power switch with LED indicator is included. You can also find air vents to help keep the amplifier cool.

Rear Panel



Direct Power Out
8 ohm 240 Watts x 2
4 ohm 400 Watts x 2
2 ohm, 1kHz, 1%THD 550 Watts x 2
Bridged mono 8 ohm, 1kHz, 1%THD 800 Watts
Bridged mono 4 ohm, 1kHz, 1%THD 1100 Watts
Isolated Constant Voltage Out
200V or 140V Bridge 400 Watts
100V or 70V 350 Watts x 2
25V 280 Watts
Frequency Response
Direct Outputs (+0/-2dB) 50Hz – 50kHz
Isolated Outputs (+0/-2dB) 50Hz – 16kHz
Total Harmonic Distortion <0.05
Sensitivity (for full output) 1.02V
Voltage Gain 28dB
Input Impedance
Balanced/Unbalanced 20k/10k ohm
Damping Factor >200 (direct output)
S/N Ratio Less than 100dB below rated output (20Hz – 20kHz)
Protection Circuits Output offset voitage protection
Heat sink overheat protection
Transformer overheat protection
Load shorting protection
Power on/off protection
Front Panel Power Switch
Rear Panel Ch 1 & Ch 2 gain controls (41 click); Parallel/Stereo/Bridge Switch
Input XLR Jack x 2, Barrier Strip x 1
Output Covered Barrier Strip x 2; Heavy-Duty Binding Post
Cooling One dual speed fan
Indicators Clip: Red
Signal: Green
Protect: Yellow
Power: Red
Dimensions (HxWxD) 132 x 480 x 428mm (5.2” x 19” x 16.9”)
Net Weight 24.7 Kg (54.6 lbs)

English Data Sheet: Download
English/Spanish User’s Manual: Download