Home Theater Glossary: 14 Terms Explained
The words that show up in home theater specs, reviews and how-to guides, explained without jargon.
- 4K (UHD)
- A resolution of 3840 x 2160 pixels, four times 1080p, which lets you sit closer to a large screen before seeing pixels.
- Related: Best 4K Projectors →
- 5.1 / 7.1.4
- Speaker layouts. The first number counts main speakers, the second subwoofers and the third overhead or height speakers.
- ALR screen
- Ambient light rejecting screen, designed to reflect projector light toward viewers while rejecting light from other angles.
- Related: Best ALR Projector Screens →
- AV receiver
- The hub that decodes surround formats, powers speakers and switches HDMI sources.
- Related: Best AV Receivers →
- Bias lighting
- A soft light behind the TV that reduces eye strain and makes blacks look deeper in a dark room.
- Related: Best Bias Lighting →
- Center channel
- The speaker under or above the screen that carries most dialogue.
- Related: Best Center Channel Speakers →
- Dolby Atmos
- An object-based surround format that adds height channels for sound above the listener.
- Related: Best Dolby Atmos Speakers →
- eARC
- Enhanced Audio Return Channel over HDMI, which sends lossless audio from a TV back to a soundbar or receiver.
- First reflection points
- Spots on side walls where sound from the front speakers bounces to your ears first, a common place for acoustic panels.
- Related: Best Acoustic Panels →
- HDR
- High dynamic range video with brighter highlights and deeper shadows. Formats include HDR10, HDR10+ and Dolby Vision.
- Lumens
- A measure of projector brightness. Rooms with ambient light need more lumens than a dark dedicated theater.
- Subwoofer crossover
- The frequency below which bass is sent to the subwoofer instead of the main speakers, commonly set around 80 Hz.
- Throw ratio
- Projector distance divided by image width. A short-throw projector makes a large image from close to the screen.
- Related: Best Projectors →
- Viewing angle
- How much of your field of view the screen fills. THX recommends about 40 degrees for immersive viewing from the main seat.