Megaphone Pattern: The Expanding Top Reversal

Key Takeaways

• A megaphone pattern is a symmetrical broadening formation: a rising upper line and a falling lower line that diverge.
• It signals expanding volatility and disagreement, frequently near tops, and is read as a potential reversal warning.
• The most common mistake is trading every swing inside the megaphone instead of waiting for a confirmed breakout.
• A measured target uses the pattern height at the breakout, projected from the breakout price.

What It Is

The megaphone is the common nickname for a symmetrical broadening top. Its upper trendline rises, connecting higher peaks, and its lower trendline falls, connecting lower troughs. Because the lines slope in opposite directions, the trading range expands bar by bar.

The pattern needs at least five turning points to be valid, typically three peaks on the upper line and two troughs on the lower line. It usually forms after an advance, which is why it is grouped with reversal patterns even though breakouts can go either way.

The Intuition

Markets usually settle down as a move matures. A megaphone shows the opposite: bigger swings, not smaller ones. That widening tells you buyers and sellers are increasingly far apart on what the asset is worth.

This kind of expanding range tends to cluster around emotional moments, like a blow-off top, a string of conflicting headlines, or a regime change in sentiment. The shape itself is a caution flag. It says the calm trend is gone and price discovery has turned chaotic.

How It Works

To map a megaphone, draw the upper trendline along the rising peaks and the lower trendline along the falling troughs. Confirm a breakout only on a close beyond one of the lines, ideally with rising volume.

The height of the pattern at the breakout sets a measured move:

target = breakout price +/- (pattern height at breakout)
pattern height = upper line value - lower line value at the breakout

Because the megaphone is a broadening top, Bulkowski's broadening-top data applies: upward breakouts occur roughly 60% of the time, with an average gain near 42% on upside breaks and an average decline near 13% on downside breaks. Break-even failure rates run about 18% up and 27% down, and throwbacks or pullbacks happen around 67% of the time. Those high failure and pullback numbers are why confirmation and position sizing matter more than the shape alone.

Worked Example

Suppose a stock tops out and starts swinging wider. Its peaks rise from 100 to 106 to 112 along an up-sloping line. Its troughs fall from 96 to 92 to 88 along a down-sloping line. The range has expanded from 4 points to 24 points, a textbook megaphone.

A trader resists fading each swing because the moves keep getting larger and stops keep getting run. When price finally closes below 87 on heavy volume, the downside breakout triggers. The pattern is about 24 points tall there, so the measured target is near 63. A stop sits back inside the megaphone above the broken line, and the trader expects a possible pullback to that line before the decline resumes.

Common Mistakes

1. Fading every swing inside the funnel. The expanding range makes buy-the-dip and sell-the-rip look easy, but each swing is bigger and stops get hit. The megaphone is a place to wait, not to scalp.

2. Setting stops too tight. A stop placed just past the last pivot sits inside the next, larger swing. Either widen the stop for the volatility or skip the trade until the breakout.

3. Calling the reversal early. The megaphone warns of a possible top, but breakouts split close to evenly. Do not short the highs just because the shape looks toppy.

4. Treating a single bar as a breakout. Wait for a close beyond a trendline, not an intrabar spike, and look for a volume increase.

5. Ignoring the high pullback rate. Most megaphone breakouts retrace toward the broken line before following through. Plan for the pullback rather than getting shaken out by it.

Frequently Asked Questions

What is a megaphone pattern in simple terms? A megaphone pattern is a chart shape where price swings get wider over time, with higher highs and lower lows. It looks like a trumpet opening to the right.

How does a megaphone pattern affect investment decisions? It warns that volatility is rising and a trend may be ending, so many traders stop chasing swings and wait. They act only on a confirmed close beyond the upper or lower line, then trade the breakout with a measured target.

What is a real-world example of a megaphone pattern? A stock or index that whipsaws with progressively larger swings during a frothy top, such as a late-stage bull market blow-off, often traces a megaphone on the chart.

How can investors trade a megaphone pattern effectively? Wait for a close outside a trendline on rising volume rather than fading swings inside the range, and size positions for the high failure and pullback rates. Use the pattern height for a measured target and place stops with the wider volatility in mind.

How is a megaphone pattern different from a diamond top? A megaphone only broadens, while a diamond top broadens first and then narrows into a symmetrical triangle, giving a tighter breakout point and a cleaner stop.

Sources

1. Bulkowski, Thomas. "Broadening Tops." thepatternsite.com. https://thepatternsite.com/bt.html
2. StockCharts ChartSchool. "Chart Patterns." https://chartschool.stockcharts.com/table-of-contents/chart-analysis/chart-patterns
3. Investopedia. "Broadening Formation." https://www.investopedia.com/terms/b/broadeningformation.asp
4. Britannica Money. "Technical Analysis Chart Patterns." https://www.britannica.com/money/technical-analysis-chart-patterns

Disclaimer

This article is educational content only and is not financial advice. Nothing here is a recommendation to buy, sell, or hold any security. Consult a licensed advisor before making investment decisions.