Protection circuitry

Volume control

This control allows you to balance the output from the subwoofer to the main speakers/ amplifier in your system. This control should be set to achieve similar output level from both the main speakers and subwoofer when listening to music. A good starting point for the volume control is 4 or 5 dots from minimum.

Low-pass crossover- 40 to 120Hz

The line-level inputs sum the left and right channels together, with the resulting signal passing through an adjustable low-pass crossover before being amplified. The crossover control allows you to adjust the upper limit of the subwoofer's frequency response from 40 to 120Hz. The subwoofer's output will be reduced above the frequency you set this control to. You should set the crossover frequency to obtain a smooth and seamless transition from the subwoofer to the main speakers in your system. If your main speakers are smaller units with limited low frequency output, you may wish to choose a higher frequency (such as 100-120Hz) than you would with larger speakers which have greater low frequency output. With larger speakers, you might start with this control set lower, such as 80Hz.

A bypass switch is also provided if you wish to use an external crossover. If you are not using an external crossover, we recommend that you use the one provided within the unit for optimum performance!

Phase adjustment- 0˚/180˚

This control allows you the "reverse" the phase of the subwoofer's output signal 180˚ to correct for any possible mismatch & resulting cancellation between the subwoofer and your main speakers/amplifier. To adjust, simply listen to the system with music playing. Then move the switch from one position to the other and listen for a change in low frequency output. The correct position will have a greater amount of apparent low frequency output.

Subsonic- 20Hz/35Hz

This adjustment alters the low frequency limit of the subwoofer. In certain movie theater installations which suggest that the extreme low bass be limited, move the switch position to 35Hz and the response will be attenuated below this frequency.

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Your new subwoofer is equipped with special protection circuitry to provide maximum performance with greatest reliability.

The unit is protected against:

1)Overdriving the speaker or amplifier.

2)Overheating the amplifier.

3)Excessive drop in power line voltage.

The first type of protection circuitry which prevents overdriving of the speaker or amplifier operates constantly without being audible under most situations. In some extreme situations (sustained high output levels such as pro sound usage), the unit may shut down momentarily. This indicates operation of the thermal or undervoltage protection circuitry. If this should happen, you should reduce the volume setting or shut the unit off until normal operating conditions return. You may also want to plug the unit into a different wall outlet, as dropping power line voltage will be most noticeable under strenuous conditions.

Distortion in loudspeakers

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Nonlinear distortion is a problem which plagues all speakers. This particular type of distortion is a common problem in subwoofers, which must move large amounts of air to produce adequate levels of deep bass. Nonlinear distortion is defined as any form of distortion that moves energy from one portion of the audio frequency spectrum to another. When a single tone is applied to a nonlinear system, the result is harmonic distortion. In which some of the energy leaves the system at multiples of the original frequency. When multiple tones are applied, intermodulation tones are produced, usually as simple combinations of the input frequencies. Generally, 3% distortion is considered a reasonable amount for speakers. This means that 3% of the total energy leaving the speaker is at frequencies other than the intended input signal.

Most subwoofers on the market today however, produce much more than 3% distortion at common listening levels. Many models we have tested produce greater than 20% distortion @ 20Hz when driven to 100dB. This is a typical output level obtained in many

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HGS 12, HGS 10 specifications

Velodyne Acoustics is a company renowned for its innovation in the audio technology field, particularly in subwoofer design. Two of its standout products are the HGS-10 and HGS-12 subwoofers. These models embody Velodyne’s commitment to delivering powerful, high-fidelity sound by combining advanced technologies with user-friendly features.

The HGS-10 and HGS-12 subwoofers are designed to provide deep bass extension and superior control, making them ideal for both home theater and music listening environments. One of their main features is their use of Velodyne’s patented Digital Drive Technology. This technology utilizes advanced digital signal processing to monitor and control the movement of the subwoofer driver in real-time, ensuring that the sound quality remains consistent and distortion-free, even at high volume levels.

Both models house large, powerful drivers that are engineered for maximum efficiency. The HGS-10 includes a 10-inch driver, while the HGS-12 features a larger 12-inch driver, allowing for deeper bass response. The cabinet design of these subwoofers is also notable; they are constructed with a sturdy, well-braced enclosure that minimizes unwanted vibrations, enhancing sound clarity.

The subwoofers are equipped with a variety of connectivity options, including line-level inputs and outputs, enabling easy integration into existing audio systems. They also feature adjustable crossover controls, allowing users to tailor the frequency response to match their listening environment. This flexibility makes it possible to achieve optimal performance regardless of the room’s acoustics.

Another significant characteristic of the HGS series is the inclusion of the room control feature. This allows users to optimize bass response based on their specific room characteristics, enhancing overall audio performance. Additionally, both models come with a remote control, enabling users to make adjustments from the comfort of their seating area.

In summary, Velodyne Acoustics HGS-10 and HGS-12 subwoofers stand out for their combination of advanced technologies, powerful drivers, and user-centric features. With their ability to deliver exceptional bass performance while minimizing distortion, they cater to audiophiles and home theater enthusiasts alike, solidifying Velodyne’s presence in the high-performance audio market. These subwoofers are more than just typical audio equipment; they are a testament to the pursuit of audio excellence.