What is the equilateral triangle method?

The equilateral triangle method places the two monitors and your head at the three points of an equilateral triangle, with 60 degrees between the monitors from the listening position. The distance between monitors equals the distance from each monitor to your ears. This provides optimal stereo imaging.

What is the 38% rule and where do I measure it?

The 38% rule positions your listening seat at 38% of the ROOM LENGTH (front-to-back) measured from the front wall — the wall behind the monitors — because that point tends to fall between the worst peaks and nulls of the room's length-axis standing waves. It is a starting point, not a strict law: anywhere in roughly the 35–43% band is a sensible search range. It is NOT a side-wall clearance figure and has nothing to do with a percentage of your listening distance.

How far should monitors be from the wall?

Monitors should be either flush-mounted in the wall (soffit mounted) or placed at least 50–60cm from the rear (front) wall behind them. Placing a monitor roughly 1/4 wavelength from a boundary causes a deep cancellation null (SBIR), so avoid mid-distances; very close coupling or full soffit mounting avoids it. Rear-ported monitors need more clearance than front-ported designs.

What height should studio monitors be at?

The tweeters should be at ear height when you are in your normal working position. Most engineers sit with ears at about 110-130cm from the floor. Tilting monitors slightly toward your ears is acceptable if exact height matching is not possible.

Should monitors be placed on the desk?

Ideally no — placing monitors on the desk causes reflections from the desk surface that create comb filtering. Use stands behind/beside the desk, or use isolation pads to decouple the monitors from the desk and tilt them to the correct angle.

AudioCalcs

Monitor Placement Calculator — Equilateral Triangle Method

Calculate optimal studio monitor positions using the equilateral triangle method.

Listening Distance

Ear-to-monitor distance; in the equilateral triangle this equals the monitor centre-to-centre spacing.

Ear Height (seated)

Seated ear height from the floor; align the tweeters to this height.

Room Length

Front-to-back room length (front wall to rear wall); used for the 38% listening-position rule.

How We Calculate This

Equilateral Triangle

Monitor spacing = Listening distance

All three sides of the triangle are equal. Each monitor is angled 30° inward (60° total angle between monitors at the listening position), with the tweeters at seated ear height.

Listening Position — the 38% rule

Set your seat at 38% of the room length from the front wall (the wall behind the monitors): seat = 0.38 × room length. This lands between the room's length-axis modal peaks and nulls for flatter bass. Treat the 35–43% band as your search range, keep the setup left–right symmetric between the side walls, and keep monitors at least 0.5 m off the rear wall behind them unless they are soffit-mounted.

Frequently Asked Questions

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Last updated: February 2026

All calculations are estimates based on standard formulas. Always verify results for critical applications.