HRI (Hum Reduction Inductor)
The solid bass guitar, known as the J-Bass style, has always been popular amongst the bass players from the time it was introduced in the mid 1900s.
With its high quality ergonomic design, wide variety of tones that provides flexibility to adopt to many different styles of music, and excellent response that enable the players to express their emotions, it is easy to understand why this bass continues to be endorsed by many players. The single-coil pickup installed in the J-Bass is simply a magnetic wire wound to the Alnico rod magnet. Although this simple design is what creates the tone that attracts many players, it also makes it vulnerable to the hum noise caused by the AC source and this has always been a known problem. XOTiC/XJ-1T has achieved its popularity with its 2 single-coil pickup design similar to the J-Bass, but it also shares its vulnerability to the hum noise. We have received many requests from musicians to make improvement to this hum noise issue and most of these requests also mentioned how important it was for us to maintain the tone characteristics of the single-coil pickup.
One of the most common ways to eliminate this hum noise is use of the dual-coil pickup. It houses a reversed coil that causes a reversed phase noise, which cancels the noise wave. But many players that prefer the tone of the single-coil pickup tend to shy away from dual-coil pickup since its tone is slightly different. HRI was developed to answer this difficult request to eliminate the hum noise, while maintaining the tone of the single −coil pickup. HRI is a device that can reduce the hum noise, while minimizing the coloration of the audio signal from the single-coil. And since it is completely passive, it does not require battery or any other power source. As shown (left), all you need to do is to mount the cavity where the magnetic field radiating from the pickup can’t reach. Since 2 pickups mounted on the J-Bass have 2 different DC resistance value, inductance value and noise level, HRI is configured to be able to deal with each pickups.
We also added HRI-J4 and HRI-J5 for the 4 and 5 string models to the lineup, making it possible to mount the HRI as an addition to all of our previous XJ-1T models.