chapter 5 • troubleshooting

￿TO ELIMINATE HUM IF THE ABOVE HAS FAILED:

A)Disconnect the power from all outboard devices and tape machines except for the PEQ-450, the mixer and control room monitor power amp.

B)Plug in each tape machine and outboard effects device one at a time. If possible, flip the polarity of the plug of each device (turn it around in the socket) until the quietest position is found.

C)Make sure that all of the audio cables are in good working order. Cables with a detached ground wire will cause a very loud hum!!

D)Keep all cables as short as possible, especially in unbalanced circuits.

If the basic experiments don’t uncover the source of the problem, consult your dealer or technician trained in proper studio grounding techniques. In some cases, a "star grounding" scheme must be used, with the mixer at the center of the star providing the shield ground on telescoping shields, which do NOT connect to the chassis ground of other equipment in the system.

Line Conditioners and Protectors

Although the PEQ-450 is designed to tolerate typical voltage variations, in today’s world the voltage coming from the AC line may contain spikes or transients. These can cause audible noises, and they can stress your gear and, over time, possibly cause a failure. There are three main ways to protect against this, listed in ascending order of cost and complexity:

•Line spike/surge protectors. Relatively inexpensive, these are designed to protect against strong surges and spikes, acting somewhat like fuses in that they need to be replaced if they’ve been hit by an extremely strong spike.

•Line filters. These generally combine spike/surge protection with filters that remove some line noise (dimmer hash, transients from other appliances, etc.). A good example is the Isobar™ series from Tripp Lite.

•Uninterruptible power supply (UPS). This is the most sophisticated option. A UPS provides power even if the AC

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Alesis PEQ-450 manual Line Conditioners and Protectors, To Eliminate HUM if the Above has Failed
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PEQ-450 specifications

The Alesis PEQ-450 is a powerful equalizer that caters to both professional sound engineers and audiophiles seeking to enhance the sonic quality of their audio tracks. This innovative piece of equipment incorporates advanced features and technologies that set it apart in the crowded market of audio processing gear.

One of the hallmark features of the Alesis PEQ-450 is its dual-channel 31-band graphic equalizer, allowing users to precisely fine-tune their audio output across a wide frequency spectrum. Each channel operates independently, making it an ideal solution for stereo applications where distinct control over left and right channels is essential. The equalizer covers a frequency range from 20 Hz to 20 kHz, ensuring that both low-end and high-end frequencies are addressed, thus delivering a rich and balanced audio experience.

Another notable characteristic of the PEQ-450 is its user-friendly interface, featuring an intuitive layout of sliders that clearly indicate gain adjustments per frequency band. The visual representation of frequency bands allows sound engineers to make quick and effective adjustments in live sound environments, where precision is paramount. Additionally, the unit includes bypass switches for each channel, enabling users to easily compare adjusted sound with the original signal.

In terms of technology, the Alesis PEQ-450 employs high-quality components that contribute to a low-noise operation and a high signal-to-noise ratio, ensuring that your audio remains pristine. The unit also includes a built-in limiter for each channel, protecting against signal clipping and distortion, which is crucial when working with loud audio sources.

The rack-mountable design of the PEQ-450 enhances its usability in studio and live settings alike, making it a versatile tool for audio professionals. The durable construction ensures reliability even in demanding environments, while its lightweight nature adds to its portability.

For connectivity, the Alesis PEQ-450 supports both balanced XLR and TRS inputs and outputs, making it compatible with a wide range of audio equipment. This flexibility allows for easy integration into existing setups, whether it be for live performances, broadcasting, or studio recordings.

In summary, the Alesis PEQ-450 is a feature-rich and technologically advanced equalizer that stands out for its precision, ease of use, and versatility. Whether you are an experienced engineer or a new enthusiast, the PEQ-450 offers the tools needed to achieve exceptional sound quality.
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