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We present spectroscopy of individual stars in 26 Magellanic Cloud (MC) starclusters with the aim of estimating dynamical masses and $V$-band mass-to-light($M/L_V$) ratios over a wide range in age and metallicity. We obtained 3137high-resolution stellar spectra with M2FS on the \textit{Magellan}/ClayTelescope. Combined with 239 published spectroscopic results of comparablequality, we produced a final sample of 2787 stars with good quality spectra forkinematic analysis in the target clusters. Line-of-sight velocities measuredfrom these spectra and stellar positions within each cluster were used in acustomized expectation-maximization (EM) technique to estimate clustermembership probabilities. Using appropriate cluster structural parameters andcorresponding single-mass dynamical models, this technique ultimately providesself-consistent total mass and $M/L_V$ estimates for each cluster. Meanmetallicities for the clusters were also obtained and tied to a scale based oncalcium IR triplet metallicites. We present trends of the cluster $M/L_V$values with cluster age, mass and metallicity, and find that our results runabout 40 per cent on average lower than the predictions of a set of simplestellar population (SSP) models. Modified SSP models that account for internaland external dynamical effects greatly improve agreement with our results, ascan models that adopt a strongly bottom-light IMF. To the extent that dynamicalevolution must occur, a modified IMF is not required to match data and models.In contrast, a bottom-heavy IMF is ruled out for our cluster sample as thiswould lead to higher predicted $M/L_V$ values, significantly increasing thediscrepancy with our observations.

Dynamical masses and mass-to-light ratios of resolved massive star clusters -- II. Results for 26 star clusters in the Magellanic Clouds