True Strength Index (TSI) on Gold

What it shows

A blue TSI line and a pink signal swing around zero beneath the candles. The pink line is a 13-candle EMA of the blue, so the blue line crossing it marks a turn in the double-smoothed momentum.

How Pravex works it out

1. Start with each close minus the close before it, keeping the sign.
2. Smooth that change with an EMA over the first smoothing length, then smooth the result again with an EMA over the second smoothing length.
3. Do exactly the same to the absolute change, the change with its sign dropped.
4. TSI = 100 × smoothed change ÷ smoothed absolute change.
5. The pink signal = an EMA of the TSI over the signal average length.
6. Plugging in invented values: if the smoothed change is 0.3 and the smoothed absolute change is 1.2, the TSI is 100 × 0.3 ÷ 1.2 = 25.

Settings

Setting	Default	What changing it does
First smoothing length	25	The first, slower EMA applied to the changes. A longer value gives a steadier line that turns later.
Second smoothing length	13	The second EMA applied on top of the first. A shorter value keeps more of the recent swings; a longer one smooths them out.
Signal average length	13	How many TSI values the pink EMA covers. Drop it to 7 and the pink line clings to the blue one, so they cross on smaller wiggles.

How traders read it

The zero line is the first thing to read. A TSI above zero says up changes have outweighed down ones over the smoothed window. Below zero says the opposite. A move through zero is a slow, steady shift rather than a sharp signal.

The blue line cutting up through the pink one from under zero is the read most often described. The mirror image, a cut down from above zero, is the bearish one.

There are no overbought or oversold guides. On hourly gold the TSI rarely gets near ±100, so judge a peak against the last few peaks on the same chart.

When it misleads

Double smoothing cuts noise but adds delay, so the TSI turns after price has already turned. After a sharp spike it keeps reading strong for many candles. On gold in a sideways range, the line hugs zero and crosses the pink line repeatedly without a move behind it. A run of small candles pulls the reading toward zero.

Questions and answers

Why does Pravex start the TSI at 25 and 13?

Those are the lengths William Blau published the TSI with, and Pravex keeps them; the signal line also starts at 13. On hourly gold the 25-candle pass covers about a trading day, so the line follows swings of a day or more.

Can the TSI reach +100?

Only if every change the averages still carry was upward, so the smoothed change equals the smoothed absolute change. The averages never fully drop older changes, so real price data can come close after a long one-way run but stays under +100.

TSI vs the SMI Ergodic Indicator?

They use the same smoothing steps on the same inputs. The TSI scales the ratio by 100 and uses 25 and 13 by default. The SMI Ergodic Indicator leaves the ratio between -1 and +1 and uses 20 and 5.

Why does the TSI turn later than RSI?

The TSI runs every change through two EMAs, 25 then 13 candles, before taking the ratio. RSI uses one smoothing pass, so it bends sooner and is noisier.

Related: SMI Ergodic Indicator, SMI Ergodic Oscillator, Chande Momentum Oscillator, every indicator.