The inherent low sensitivity of 13C MRS makes direct 13C detection challenging. Moreover, the 13C-1H heteronuclear J coupling requires double tuned 13C-1H coils to perform proton decoupling during 13C signal acquisition. High sensitivity can be achieved over a large field-of-view using array coils. We aimed to design and build a 4 channel 13C-4 channel 1H transceiver phased-array coil for 13C-MRS studies in humans at ultra-high field. Electromagnetic performance of the coil was evaluated by FDTD simulations in calf muscles at both frequencies. Finally, 1H-decoupled 13C resonance of Glycogen C1 was successfully detected in volunteer calf muscles at 7T.