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Subwoofer Problems

A subwoofer is, to put it simply, a complete loudspeaker. It is integral to the reproduction of ‘Bass’ (low-pitched audio frequencies). A subwoofer would have a frequency range of about 20–200 Hz for home users. Professionals who work with sound systems have task specific frequencies, but they normally use subwoofers of frequency below 100 Hz for live sound, and less than 80 Hz in THX-approved systems. As is the case with any modern invention, subwoofer users have faced problems that have needed answers from Experts. Read below where subwoofer troubleshooting questions have been answered below.

What can be done if the subwoofer output does not work on VSX-1020-K?

The first thing that can be done is to check the DB rating for the subwoofer. Is it compatible with the VSX-1020-K receiver? If the answer is yes, then the next thing to check is if the LFE is set to ‘yes’ or ‘on’. In case these aspects are fine, and there are still no output, the microprocessor should be reset. If the problem is still not fixed, it could mean the subwoofer’s pre-out is shot. This could require a replacement of the board or the signal processor.

What if there is no bass output from a powered subwoofer connected to a Onkyo TX-SR800 receiver?

The first thing to check is the subwoofer cable. The only way to find out if the problem lies with the cable is to swap it for another cable. Any standard Red or White RCA cable can be used to test this problem. A common dilemma faced here is some RCA cables have only one pin at either end, but the subwoofer has two inputs (left and right). In such a case, the cable can be inserted into either input. There might be a problem in locating the correct subwoofer pre-out to connect the cable to. The manual might mention a pre-amp out connector. In recent models there is a dedicated (and labeled) subwoofer output. The Onkyo TX-SR800 receiver has a pre-out labeled ‘Sub-right’. This normally fixes the problem.

How can the KLH ASW8-100B subwoofer be wired up to Surround Sound equipment?

To wire up the KLH ASW8-100B subwoofer to Surround Sound equipment, the RCA cables need to be connected to the sub out on the AVR. Then the red colored mono input should be hooked on the subwoofer. The minimum recommended length of the cable is 4 meters to allow more freedom of choice in placing the equipment. Once this is done, the equipment should be set to ‘Auto’ and the crossover and volume controls be adjusted to the user’s listening preferences. One must keep in mind that the phase switch has to be set to normal and the equipment has to be powered up by plugging it into a power socket. The questions answered above cover a few typical subwoofer problems. However, each model and equipment has their unique set of problems, which, if not resolved by basic subwoofer troubleshooting, are best referred to an Expert.
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