About Room Equalization

This section gives some background on room equalization. As a subwoofer plays in a room, the reflections of the sound waves off the walls create “standing waves,” that is, places in the room where certain frequencies are louder and others are diminished. In addition to standing waves, every room will also have locations where cancellations of the sound waves are like black holes that no amount of attenuation can fill. Thus as a general rule it is better to “cut down” a peak of response rather than to “boost up” a valley (i.e. possible black hole) of response.

In general, you are looking for a frequency response that is +/– 3 dB at all frequencies (it is highly doubtful that your ears can tell a response that is any better than this). The response will always roll off at the low end (according to the settings of the subsonic filter), and there should be no dip or peak at the crossover frequency with the satellites. While the goal is perfectly flat response, this may not be possible in the higher frequencies of the subwoofer’s response due to peaks or valleys introduced by the satellites.

Care of Your Digital Drive SMS - 1

Do not use any harsh detergents or chemicals to clean the chassis. Abrasives, detergents, or cleaning solutions may damage the finish on the chassis. We recommend using a damp cloth to clean the chassis. During normal conditions, your new SMS-1 may be left on continuously without any problems. If you plan to leave the SMS-1 unused for an extended period of time, we recommend that you unplug the unit.

Troubleshooting and Service

If you should experience a problem with the operation of your SMS-1, please check all of the following before seeking service. Following is a simple troubleshooting guide to assist you.

1.Verify unit is plugged in and power outlet used is active.

2.Is the unit receiving an input signal from your source? A good way to test this is to connect the EQ audio out to the LFE input on the back panel, then enter setup mode (see Step 6). The woofer should play the sweep tone used for room EQ.

3.Have all controls on SMS-1 (volume, crossover, phase, etc.) been properly set?

The following conditions require service by a qualified technician:

1.The power supply or cord has become damaged.

2.The unit does not appear to operate normally or exhibits a marked change in performance.

3.The unit has been exposed to water.

4.Some part of the chassis or circuitry is physically damaged.

Software Updates

At the heart of Digital Drive functionality is the customized software. From time to time, Velodyne will publish updates to the Digital Drive software. To determine if your unit is a candidate for a software upgrade, observe the software version number in the upper left corner of the Main Screen (e.g. V2.1). Then visit www.velodyne.com and observe the version number of the software available for download. If this version is higher than the version in your unit, you may want to upgrade the software.

To upgrade the software, you will need an IBM-compatible PC with an available RS-232 9-pin serial
port, and a male-to-female “Mouse Extension” serial cable. This cable is available from any
computer store, your local Velodyne dealer, or directly from Velodyne. Next, proceed to the
Velodyne web site and click on the link to download the software. Upon download, run the software
and it will instruct you on completing the update process.
.w w w . v e l o d y n e . c o m	Thank you for purchasing a Velodyne!
	Digital Drive User’s Manual 38