My DVE has a single card with all 3 filters (red, green, blue).
Much has been made of a perceived problem with DVE's subwoofer test tone levels. Here is the
manufacturer's explanation.
Setting Subwoofer (often mistakenly called 'LFE') Levels: At what level should the LFE channel be set in the Dolby Digital 5.1 audio system? During system setup you need to adjust the subwoofer level, not the LFE level. The information from the LFE channel will generally be sent to your subwoofer, often along with the low frequency signals from all other channels, but you don't generally adjust the LFE level itself. What you do adjust is the level of the subwoofer relative to the other channels so that they are at the same level at the listening position. Don’t forget to move the meter back and forth, as shown in the video, and take an average of what you read. Once all of the channels are equal in level, the main volume control can be set for the +75 dB reference level called out in the program.
Confusion has come up about setting this level because the LFE channel in the Dolby Digital 5.1 system is actually recorded 10 dB below the levels of the other five channels of audio. This is done to increase the 'headroom' available to large signals in the LFE track. Your Dolby processor will take care of this level offset for you automatically, it is not something you should be concerned with during system calibration.
Problems setting up both Dolby Pro-Logic and Dolby Digital 5.1 levels for bass information: When I check the subwoofer level between the calibration for Dolby Pro-Logic and Dolby Digital 5.1 (AC-3) there is a 10 dB difference in the subwoofer level. What’s wrong? Why is this happening? Low bass information is recorded at 'normal' levels in the Pro-Logic system and 10 dB below 'normal' in the LFE channel of the Dolby Digital 5.1 system. There are a number of early generation audio processors that either don’t have enough memory to independently set up bass levels in each system or don't readily allow access to that memory to the average owner. We’ve had a large number of reports of subwoofer level being off by 10 dB when switching between the two forms of Dolby Surround audio. Most audio processors will take care of this difference between the two systems for you automatically. If you find that it is a problem in your audio system, we strongly suggest that you carefully read the owner’s manual for the audio processor. Look for an ability to independently set the bass level in each of the two Dolby systems. If you can’t find the help you need there, contact your dealer or the manufacturer of the product.
