Power spectral density ${\widehat{E}}_{+}$ for the dominant Elsasser variable in the Alfvénic stream and estimates of the power density at the break position (symbols). The yellow line is the fit in the inertial range f ∈ [f₁,  f₂] and the white line is an extension to higher and lower frequencies. We find the frequency break and its energy by fitting to a line $\log {\widehat{E}}_{+}(\log f)$ in the range f < f₀, with the constraint that the spectral density at the break, ${\widehat{E}}_{+}(f_c)$, must lie on the extension of the inertial range fit. To estimate the uncertainties we vary the fitting range of the second fit. We plot in green the resulting low-frequency fit (line) and the position of the break, ${\widehat{E}}_{+}(f_c)$ (symbol), using darker color scale as the boundary of the fit moves to lower frequencies, f₀ = f₁/4,  f₁/8,  f₁/16,  f₁/32.