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Traditionally the dynamo theory describes the large-scale magnetic field generation in the turbulent plasma systems, for example, in the convective stellar shells or galaxy disks. But, the dynamo equations, obtained by averaging of the magnetic induction low over a random velocity field also describe the smallscale, so called turbulent, dynamo, a characteristic feature of which is magnetic energy growth with zero first moment. The first linear small- scale dynamo model was suggested by Kazantsev for short-correlated in time turbulence. In this report we speculate about the cascade model, which is obtained by Fourier transformation of mhd-system on a spectral shell. This model is generally nonlinear and its nonlinearity provides the mutual exchange of magnetic/hydrodynamic energy and helicity between the shells. We compare the numerical results of Kazantsev model and the cascade one, highlight the linear and nonlinear dynamo regimes, show the dependence of dynamo-generation on the hydrodynamical properties of the turbulence. Basing on the obtained results, we discuss a possible role of small-scale generation in the large-scale dynamo by reverse helicity transport along the specter.