Harman 286 Problems, Possible Causes, Solutions, Noise Rushups, Hiss Buildup, Audible Distortion

Section 4 Problems, Possible Causes, Solutions

286s

Section 4 - Problems, Possible Causes, Solutions

Always verify that the problem is not in the source material being fed into the 286s, or in the other parts of the system. If you still have problems when using the 286s, consider the following remedies.

Noise Rushups, Hiss Buildup

Higher DRIVE settings on the compressor often add gain to the signal. If the signal already has substantial hiss, the compression can actually increase the hiss. As a compressor releases and the gain of the input signal increases, background noise and hiss can increase. This is called noise rushup. Remedy this by using compression conservatively. Also, to reduce noise rushups, especially during pauses, lower the Compressor DENSITY setting. For both cases, set the Expander/Gate to match the compressor’s release time, thereby gating out the noise or hiss as much as possible without truncating the signal.

Increased hiss can also result from high frequency “detailing.” The HF DETAIL enhancer estimates how much high frequency boost is appropriate for a given input signal. If the signal is dull but noisy (e.g., vocals recorded to a bad cassette), the HF DETAIL will make it brighter and can pull up hiss to objectionable levels. (The hiss will often be audibly modulated by the material because the HF DETAIL is adaptive to the material.) Reduce the setting of the HF DETAIL control until the effect is no longer objectionable.

For multitrack studio applications, consider gating out the hiss during the initial recording, then adding HF DETAIL enhancement afterwards, during mixdown.

Audible Distortion

With certain combinations of controls, especially when they are used at more extreme settings (towards fully clockwise), distortion or artifacts may occur. In this case, lessen one of more of the controls in use. For example, higher DRIVE settings on the compressor often add gain to low-level signal, especially when used in conjunction with other controls. To reduce distortion, simply reduce the compression setting. If you still want more compression, return the compression to its previous setting, and reduce one or more of the other controls which commonly increase gain (e.g., Enhancer DETAIL controls, MIC GAIN, etc.).

Setting the DENSITY control higher than the 12:00 position can sometimes cause audible distortion in the bass because the very fast release time begins to modulate each individual cycle of the bass waveform. If this occurs, turn down the DENSITY control. (Patented circuitry in the 286s greatly reduces this effect when compared to many other compressors operated at equally fast release times).

Sound Cutting Off

Higher Expander/Gate settings can cut off sounds prematurely, specifically after a sudden transient or loud note has decayed. This could result in unintelligible vocals, incomplete chords, inferior cymbal splashes, lost reverb tails, etc. To retain the complete input signal, but still maintain required expansion and gating (e.g., to reduce settings until the complete signal is adequately restored). This means that you should set the Expander/Gate controls so

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