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We present a novel configuration for high spectral resolution multiplexing acquisition based on the Hadamard transform in stimulated Raman scattering (SRS) microscopy. The broadband tunable output of a dual-beam femtosecond laser is filtered by a fast, narrowband, and multi-channel acousto-optic tunable filter (AOTF). By turning on and off different subsets of its 8 independent channels, the AOTF generates the spectral masks given by the Hadamard matrix. We demonstrate a seamless and automated operation in the Raman fingerprint and CH-stretch regions. In the presence of additive noise, the spectral measurements using the multiplexed method show the same signal-to-noise ratio of conventional single-wavenumber acquisitions performed with 4 times longer integration time.