Speaker placement calculator
Enter your room and where you sit. For each speaker of a 5.1, 7.1 or Dolby Atmos layout you get an angle inside the range Dolby’s home guideline publishes for it, and the spot on a wall or the ceiling where that angle lands in your room — with anything the room cannot hold flagged rather than moved somewhere Dolby does not describe.
This is planning geometry, not acoustics. It puts each speaker where an angle inside Dolby's published range from your seat meets a wall or the ceiling of a plain rectangular room — it does not know about doors, windows, a sloped ceiling, furniture or how your room sounds, and it does not place subwoofers, which are placed by ear. Where Dolby gives a range but no single angle, the angle used is the middle of the range, and the table says so. Measure, mark the spots with tape and listen before you cut a hole in the ceiling.
Your room
Depth runs from the screen wall to the back wall; “left” is your left facing the screen. Leave the last box empty for a seat centred in the width. Ear height is taken as 3 ft 11 in, Dolby’s typical seated ear level.
In a 14 ft × 18 ft room, 5.1.4 Atmos puts 9 speakers — the top front pair on the ceiling 5 ft 1 in ahead of your seat. 4 had to move within Dolby's range to fit.
Where each speaker goes
Subwoofers (1) are not placed by angle — put one at your seat and crawl the room for the smoothest bass, as the speaker placement guide describes. “Closer than 2 ft 11 in” borrows Dolby’s minimum distance for Atmos enabled speakers as a caution for every speaker. Different distances are normal: set each one in the receiver.
The room, drawn
Will your receiver run it?
Channel counts are the maker’s stated figures from our catalog, not our measurements. Subwoofers run from a line-level output and are not counted. A receiver whose figure isn’t stated is shown as not stated, never as a pass or a fail.
Questions
Where should Dolby Atmos height speakers go?
Above and slightly in front of and behind the main seat. Dolby's home guideline puts the top front pair at 45 degrees of elevation from the seat — adjustable between 30 and 55 — and the top rear pair the same angle behind it, each pair spaced between half and seven-tenths of the width of the whole layout apart — the calculator uses six-tenths. With only two overhead speakers (5.1.2), Dolby draws a top middle pair between 65 and 100 degrees, nearly straight above the seat. On a 9-foot ceiling, 45 degrees lands a little over 5 feet in front of your head.
What angles does Dolby give for the ear-level speakers?
Measured from the line between your seat and the screen: the center at 0 degrees, front left and right at 22 to 30 degrees either side, surrounds at 90 to 110 degrees, and in a 7.1 layout the rear surrounds at 135 to 150 degrees. All of them sit at seated ear height, which Dolby puts at about 3.9 feet (1.2 metres). The calculator aims the front pair at 30 degrees, the figure Dolby's text uses, and the surrounds and rears at the middle of their ranges.
What if a speaker can't go where the angle says?
The calculator tries every other angle inside Dolby's range before giving up, and marks the speaker as adjusted when it had to. It also keeps every speaker at least a foot from the corner it would sit in — our buildability rule, not Dolby's — and when no angle in the range clears the corner it uses the one with the most room and says it is within a foot of the corner. When no angle in the range reaches the wall or ceiling spot a speaker belongs on — the front left for a seat far back in a narrow room, say, or a top front speaker for a seat right against the front wall — it is flagged as not fitting, with the seat move that would fix it, rather than moved somewhere Dolby does not describe. Speakers that end up at different distances from the seat are normal: set each distance in the receiver, which is what Dolby recommends when equal distances are impossible.
How high does the ceiling need to be for overhead speakers?
Dolby's guideline puts overhead speakers at two to three times the height of the ear-level speakers. With those at seated ear height, about 3.9 feet, that is roughly an 8 to 12-foot ceiling. Lower than that and the overheads sit close to your head, where you hear each speaker rather than a sound field; the calculator flags a ceiling outside that ratio. Dolby Atmos enabled up-firing speakers are the alternative it describes for low or awkward ceilings.
Where the numbers come from
Every range is read from Dolby’s Dolby Atmos Home Theater Installation Guidelines (December 2018): the plan and side-view figures for the 5.1.2, 5.1.4 and 7.1.4 layouts, and the text on overhead height and spacing. For why each layout exists and which to choose, read Dolby Atmos speaker placement and 5.1 vs 7.2 vs Atmos; then browse speakers and AV receivers, or put a system together in the builder.