GROUND LIFT

A ground lift is provided for the Balanced Inputs. In the normal (out) position of the push switch, Pin 1 on the XLR connector is grounded. In the Lift (in) position, the ground on Pin 1 is disconnected. When using the Balanced Inputs, always be aware of the position of the ground lift switch. This function only affects the Balanced Inputs and does not affect the Unbalanced Inputs.

SLAVE OUTPUT

A 1/4" Slave Output (some call it a "patch-through") is provided in the event you want to "daisy chain" more than one power amp at a time. To use the Slave Output to run an additional power amp, run a shielded patch cord from the Power 750 Slave Output to the input of the additional power amp. Whatever signal is coming into your Power 750 will be available at the Slave Output, where the signal can be sent to the additional power amp of your choice (preferably ANOTHER SWR Power 750!). The Volume controls on the Power 750 do not affect the level of the Slave Output. The Slave Output can also be used as an unbalanced record out or a monitor send.

SPEAKER OUTPUT SECTION

The following section of the manual will deal with the proper connection of speaker cabinets to the power amplifiers in the Power 750. Some of this ground has already been covered in the "Getting Started -Connecting Your Speaker Cabinets" section in the beginning of the manual. This is meant to supplement that section and provide information in greater detail, as power amplifiers, impedance and speaker cabinets are all crucial in determining how best to operate your new Power 750.

HOW IMPEDANCE AFFECTS POWER RATINGS

People often have questions about impedance. What is it? The root of the word "impedance" is the verb "impede", which means to block or resist. That's what impedance is - resistance to power.

Power amps do not have a pre-determined impedance. They deliver power at whatever impedance the speaker cabinet tells it to. That's why you hear the term "slave amp" - amplifiers only do what they're told. So if someone tells you that they have a "4 ohm power amp," their terminology and under- standing of the concept is off the mark.

Unlike power amps, every speaker cabinet has a pre-determined impedance rating measured in "ohms." In most cases this rating is either 4 or 8 ohms (though there may still be some older 2 ohm models out there). The higher the impedance of the speaker cabinet, the more resistance to power it will offer. The lower the resistance of the speaker cabinet, the less resistance to power it will offer. In other words, higher impedance means less power can enter the speaker cabinet. Lower impedance means more power can enter the speaker cabinet.

You may be thinking that you've found the solution to the universe - just use speaker cabinets with really low impedances and you can get skull-crushing power out of your amplifier, right? Wrong. There's a catch. Power amps have limits as to how low an impedance they can drive safely. This is what's known as an amplifier's "Minimum Impedance Rating." If you try and operate a power amp below its minimum impedance rating, it will give you lots of power for about five minutes, then overheat, short out and fail completely. In other words, the lower the operating impedance of the amplifier, the hotter it will get.

POWER 750 POWER AMPLIFIER MINIMUM IMPEDANCE RATINGS

Here's what this means to the power amp in the Power 750. The Minimum Impedance Rating of the Power 750 is 2.6 ohms. This means that you can connect:

a)two 8 ohm cabinets

b)one 8 ohm and one 4 ohm cabinet

c)three 8 ohm cabinets

Damage to the power amplifier in your Power 750 may occur if speaker enclosures with total impedances less than the minimum loads listed above are connected to the speaker output section. The owner's manual that came with your speaker cabinet should state its total impedance. On SWR speak- er enclosures, the total impedance is generally indicated on the speaker's input panel.

So how do you determine the total impedance of two cabinets hooked up to your Power 750? Here's a quick key of the most common setups:

One 8 ohm enclosure + one 8 ohm enclosure = 4 ohms total impedance (OK)

One 8 ohm enclosure + one 4 ohms enclosure = 2.6 ohms total impedance (OK)

One 4 ohm enclosure + one 4 ohm enclosure = 2 ohms total impedance (NOT OK!)

POWER 750 • 7

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SWR Sound 750 owner manual Ground Lift, Slave Output, Speaker Output Section, HOW Impedance Affects Power Ratings

750 specifications

The SWR Sound 750 is a powerful and versatile bass amplifier that has garnered a solid reputation among musicians and sound engineers for its exceptional performance and reliability. Ideal for both live settings and studio recordings, the SWR Sound 750 blends cutting-edge technology with user-friendly design, making it a top choice for bassists of all levels.

One of the standout features of the SWR Sound 750 is its impressive power output. This amp delivers 750 watts of pure power at 4 ohms, ensuring that users can achieve a loud, punchy sound in any environment. The onboard power management system also optimizes the amplifier's performance, allowing for dynamic control and responsiveness to playing styles.

The SWR Sound 750 incorporates advanced tone-shaping technologies that enable musicians to sculpt their sound with precision. It features a 4-band EQ section, allowing for detailed adjustments to the high, mid, and low frequencies. This gives bassists the ability to enhance their tone, whether they are looking for a deep, rich low end or a bright, cutting high end. Additionally, a built-in compressor helps to smooth out the tonal inconsistencies, providing a consistent sound across various playing dynamics.

Versatility is another key characteristic of the SWR Sound 750. It includes multiple input options, catering to both active and passive bass guitars. The amp also features a balanced XLR line out for seamless integration into live sound systems, making it suitable for gigging musicians who require reliable connectivity and high-quality sound.

Durability is crucial in a performance environment, and the SWR Sound 750 is built to withstand the rigors of the road. The sturdy chassis and robust components contribute to its long-lasting performance, ensuring that it remains a reliable choice for touring musicians. Additionally, its lightweight design makes it easy to transport without sacrificing sound quality.

The SWR Sound 750 is more than just an amplifier; it is a comprehensive solution for bassists. With its powerful performance, advanced features, and rugged construction, this amplifier has established itself as a trusted choice for musicians seeking to elevate their sound in any scenario, be it on stage or in the studio. Whether you are playing in a small venue or a large concert hall, the SWR Sound 750 is designed to deliver powerful, professional-grade audio that enhances the overall performance.