Question:
Dear Big Picture Big Sound,
My new home theater receiver has Dolby ProLogic IIz (PLIIz) decoding with an option for front height channels. If I do this, I cannot use the rear surround sound speakers. Is this a worthwhile tradeoff? Is there anything out that that takes advantage of this height channel information?
Thanks,
-Height Challenged in Hackensack
Answer:
Dear HC,
The height channel is the latest trend in home theater audio. Whether it catches on or becomes the next HDCD, it's too early to tell. In addition to selling more A/V receivers and speakers, the height channel can add some real value to the listening experience by enhancing the sense of immersion in a home theater environment. After all, in real life, sound comes from all around you and above you, not just in front of you and behind you. Helicopters and planes generally fly over your head, and thunder comes from the clouds above you. Why shouldn't your home theater have a way of representing these kinds of sounds accurately?
We recently spent some quality time with Onkyo's PLIIz-equipped HT-RC160 receiver, along with Atlantic Technology's System 2400 speaker system augmented with their 1400 SR-z height channel speakers. On certain material, the PLIIz processing created a virtual wall of sound from the front half of the room, with sounds even creeping up onto the ceiling and beyond. But admittedly, for most material, the presence of the height channel speakers went unnoticed.
Here are a few scenes on existing Blu-ray Discs and DVDs that will help you to hear the effects of PLIIz-processing (thanks to Craig Eggers from Dolby, for the suggestions):
These scenes are just a few that allow you to hear the effects of height channels in multi-channel playback. If and when Dolby can convince movie makers, game designers and/or music producers to start encoding their material with a matrixed PLIIz height channel, I'm sure height channels will become more compelling, but for now it is mostly just a mild enhancement to the home theater experience. In the interest of being prepared for the future, we do recommend getting a receiver with PLIIz decoding, even if you don't choose to deploy those front speakers right away.
As for the choice of front height vs. rear surround speakers, some receivers do ask you to make this choice, as they only have enough amplifiers for seven speaker channels. But some receivers support both rear surround channels and front height speakers (9.1 surround). If your specific receiver only supports one or the other (height or rear), then it's a personal choice which to deploy. The fact is that 5.1 channel surround is quite sufficient in most rooms for reproducing an enveloping and immersive surround sound experience, so if you choose to enhance this surround soundscape with rear channels or with front height channels, you shouldn't be too concerned about what you're missing.
Regards,
-Chris
Related Articles:
