Speaker Size Calculator
Enter the room size, how far you sit from the speakers, their sensitivity and how loud you want peaks. The calculator suggests a woofer size for the room and the amplifier power per channel.
- Speaker size
- Amplifier power
- Subwoofer
Sensitivity is on the spec sheet, in dB at 1 W and 1 m.
Bigger rooms need bigger woofers, and every 3 dB louder needs double the power. A 15 × 12 × 8 ft room is 1,440 ft³, so 5.25 to 6.5 in bookshelf speakers suit it. At 3 m with 88 dB speakers, 100 dB peaks need about 290 W per channel.
Speaker size by room
By room volume. Search for a room.
| Room | Volume | Woofer |
|---|---|---|
| Small bedroom | Under 1,000 ft³ | 4 to 5 in |
| Bedroom or study | 1,000 to 2,000 ft³ | 5.25 to 6.5 in |
| Living room | 2,000 to 3,500 ft³ | 6.5 to 8 in |
| Large lounge | Over 3,500 ft³ | 8 to 10 in plus a sub |
Inches.
Distance and amp power
100 dB peaks. Slide the distance.
The speaker is drawn with its power.
How to size speakers
Room to speaker. Step through it.
Room
Measure it.
Keep speakers away from corners for cleaner bass.
Bookshelf, tower or sub
Speaker types. Compare them.
Compact.
Floor standing.
Bass only.
A subwoofer lets small speakers sound big.
Before you buy
Speaker checks. Tick each item.
Tick each item as you go.
Match the amplifier's impedance to the speakers.
What you get
Speaker sizing. Each tile explains one result.
Size.
Watts.
Room.
Seat.
Advice.
High sensitivity speakers need much less amplifier power.
Frequently Asked Questions
No question matches that search.
What size speakers do I need for my room?
About five to six and a half inch woofers for most bedrooms and studies.
How many watts do I need?
Often fifty to one hundred watts per channel for a living room.
Does a bigger room need bigger speakers?
Yes. Bigger woofers move more air and fill a bigger space.
What is speaker sensitivity?
How loud a speaker plays with one watt measured at one metre.
Do I need a subwoofer?
It helps in bigger rooms and for films.
How far should speakers be from me?
About the same distance as they are apart from each other.
Sound that fills the room
Match speakers and power to the room and music sounds full without strain.
More size calculators
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