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Home Sale & Promotions PS AUDIO Humbuster 3 DC Voltage Blocker

PS AUDIO Humbuster 3 DC Voltage Blocker
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PS AUDIO Humbuster 3 DC Voltage Blocker

Price per Unit (each): SGD$250.00
Number eachs in packaging:1
Number eachs in box:1
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The Humbuster is designed to block DC voltage on the AC line. DC voltage on the AC line can cause mechanical hum to appear in your equipment. Mechanical hum is described as being that noise generated by the power transformer inside a piece of AV equipment.

The Humbuster will have little effect on hum and noise heard through the loudspeaker or headphones. In some instances, it is possible that the reduction of mechanical noise in the unit’s internal transformer may reduce the magnetic field of the transformer and thereby reduce hum heard through a loudspeaker.

All AC power lines have a small component of DC (battery type voltage) on the line. Typically this DC is held to a very low level and causes only a few problems. However, many homes AC performance is not “typical” and this DC component can be quite high.

In fact, it’s high enough to cause an asymmetry that “pushes” the voltage in the transformer in one direction and partially saturates the core of the transformer, causing it to buzz. In addition to buzzing noises, the transformer is also at a performance disadvantage because its core is not working properly.

Transformers work best when there is absolutely zero DC presented to them. This is because transformers are AC devices, not DC devices. Transformers need to change the direction of their magnetic fields multiple times per second in order to function properly. When there’s DC on the line, it forces the transformer to stay polarized in one direction and this make the transformer a little crazy - and it hums and complains in response.

The Humbuster removes the DC component from the AC line and either stops or significantly reduces the buzz and vibrations caused by DC. How effective the HB-III is depends on just how much DC there is on the line and what the quality of the transformer inside your unit is.

Humbusters work by placing a simple network of power rectifiers and power capacitors in an arrangement that removes the direct coupling at the AC’s zero crossing point. This blocks the DC from coming through. Then, just a volt or so above and below the zero cross point, we direct couple the AC signal back again. It’s simple, yet effective.

We recommend one HB-III for each piece of equipment that is producing internal mechanical hum if possible. While it is perfectly acceptable to run multiple pieces of source equipment from a single HB-III it is recommended that larger power draw equipment, such as a power amplifier, be limited to its own HB-III for power.

Last Updated: Wednesday, 25 April 2018 08:15