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Unwanted Noise, Hum, Buzz, Crackles, DistortionUpdated 9 months ago

The most common source of unwanted noise is external interference. A range of elements, including electromagnetic interference (EMI), radio frequency interference (RF), ground loops, nearby cell phones, computers, dimmer switches, and numerous other devices, can contribute to this issue. It's worth noting that such interference can affect any audio product, not exclusively Fractal Audio devices. Sometimes, the culprits may even be devices located outside your home! 

Guitar cables and pickups — even humbuckers — are sensitive to these sources of noise. If the noise disappears when you turn down your guitar, it's likely the noise is being picked up or generated by your guitar or cable, rather than your Fractal Audio device. It's crucial to note that interference isn't solely an issue with low-quality cables; even high-end cables can be sensitive to electromagnetic and radio frequency interference. Furthermore, any cable defects can lead to unwanted noises like crackles and buzzes.

Another good test is to ensure that sound issues aren't isolated to your amp, speakers or monitors. Disconnect all audio, MIDI, and USB cables and compare the signal from the headphones jack if your device has one. (If your unit doesn't have a headphone out, try a different mixer, monitor, amp, etc.)

GAIN

In any rig, increasing gain also amplifies any background noise. This principle is especially important to keep in mind when using amp modeling. Our products are easily able to produce high-gain tones at low levels — the key benefit being that you can obtain absolutely amazing "cranked" tone without extreme and even dangerous volume levels. This is great, but it can lead to the temptation to use "insane" gain settings — higher than would be likely or even possible in an analog rig. In addition to worsening noise, excessive gain can muddy your sound and compress its dynamic range, resulting in a uniform and less expressive tone that is difficult to distinguish. Above all, these considerations underscore the importance of eliminating noise at its source.

NOISE GATES

Almost all of our products include Noise Gate capability which provides an effective way to combat problem of environmental or guitar-related hum or buzz. It's best to eliminate noise at its source. In high-noise scenarios, however, gates can introduce artifacts due to the settings required to tackle the extreme noise (high threshold and ratio, fast attack and release).

GUITAR PROBLEMS

Noise problems can also be guitar-related (fret buzz, induced hum, crackles, etc). Try a different guitar or consult the services of an expert luthier.

HUMBUSTER CABLES

Most full range ("FRFR") setups will utilize the XLR outputs of your Fractal Audio device into the balanced inputs of mixers, monitors, and other devices. For these applications, XLR cables or XLR-to-TRS cables are typical. XLR cables are more resistant to RF/EMI than standard guitar cables. 

When not using XLR calbes, you can use standard 1/4" patch cables, but there is a better option! Humbuster™ technology — available on the 1/4" outputs of many of our products — can significantly reduce unwanted noise due to ground loops. For this to work, you must use a special cable. High quality Humbuster™ Cables are available for sale in our store at https://shop.fractalaudio.com/fas-humbuster-cable/ and can also be ordered in custom lengths at https://btpa.com/FAS16-XX.html

GAIN STAGING

Gain staging is the process of managing the levels of your audio signal at each point in the signal path to prevent unwanted distortion or noise. This process is crucial because improper gain staging can lead to a variety of sound quality issues. 

Start at the input of your Fractal Audio device. You want your input level to be high enough for good signal-to-noise performance, but not so high as to cause input clipping. Refer to your owner's manual for instructions on properly setting input. The Axe-Fx III, FM9, and FM3 have settings for adjusting Input levels under Setup > I/O > Input. Note that input level adjustments do not affect gain levels. As you adjust the input level to the A/D converter, the output is compensated accordingly, so what you hear is not affected by how you set these controls.

Levels inside your Fractal Audio device are also important, and meters or indicators are provided help you to read these. If you notice the onboard Outputs clipping, this means your presets are too hot. Your owner's manual includes a section on properly setting preset levels. 

Output levels are also key. Our products have front panel output level controls, which should be set appropriately to not overload the inputs of whatever you are connected to. The Axe-Fx III, FM9, and FM3 have settings for -10 dBV ("consumer") or +4 dBu ("pro"), which should ideally be set to match your connected amp, mixer, monitors, etc. 

KEYWORDS: noise, ground loop, buzz, buzzing, hum, humming, static, clipping, distortion, artifacts, artifact.    

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