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PS AUDIO - HUMBUSTER III

Got Hum? Bust It With PS Audio's Humbuster 3!

Many pieces of equipment have noisy transformers, this includes large power amplifiers and projectors as well as small preamplifiers, digital converters and even integrated amps. If you hear or feel hum coming from the transformer in your equipment, chances are the Humbuster 3 can help. Hum inside equipment is generally caused by DC voltage on the AC powerline. This voltage makes transformers buzz and hum and the Humbuster 3 eliminates this problem.

The HB3 is capable of handling any size power requirement from the largest to the smallest power requirement; Need more than one piece of equipment "busted"? Simply purchase a Juicebar II power extender and place this after the HB3. No sonic degradation or dynamic restriction with the HB3. Try it at home and if it doesn't do the job, send it back!

Connect the HB3 to the wall and your component to the HB3 and voila!  The hum’s gone, like magic!  How does the HB3 work? 

By eliminating the DC component on the AC line. 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 miniscule problems.  However, many homes are not “typical” and this DC component can be quite high.  In fact, if 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, this will cause the transformer 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 many 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 drives the transformer a little crazy - it hums and complains in response. 

The HB3 is almost like magic in the way it removes the DC component from the AC line and either stops or significantly reduces the buzz and vibrations caused by DC.  How effective the HB3 is, will depend on just how much DC there is on the line and what the quality of the transformer is.  Furthermore, the HB3 improves the performance and, in some cases, lowers the heat produced by power transformers when it removes the DC. It’s the elimination or reduction of the DC component on the AC power line that really helps to lower noise. 

The HB3 removes nearly 1 volt of possible DC from the AC line and every piece of gear, from Power Plants to amplifiers, to preamps and video projectors benefit from its addition. 

How does it work?

HB3 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 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. 

Are there any restrictions?

Not really.  The HB3 is built from huge 50 amp devices and is not current limiting or restricting in any way as long as you are not asking more from it than you would from the wall socket.  Placed between any size load that a standard 15 or 20 amp wall outlet can power, the output of the HB3 is DC free and AC clean and can safely and effectively power anything you want to throw at it. You can feed the HB3 balanced or standard single ended AC power.  The HB3 will accept any AC voltage from 100 to 240 volts AC. 

HB3s do not replace an Ultimate Outlet or a Power Plant, but are used in addition to them to augment their performance.

How do I know if I need one?
Take a moment to place your ear close to each piece of gear in your setup when it's on and functioning.  If there's a noticeable humming or buzz inside, you're a candidate for an HB3. Sometimes this noise is not audible because of the time of day.  You might just notice that you hear a buzzing sound in your system (not through the speakers) at some time in the day but not others.  This is quite typical and this would also qualify as a candidate for a HB3. Or, you can simply assume you'd be better off making sure there's no DC getting through and connect your power amps and source gear through one or several HB3s and be done with it.