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Phenyl radical (C$6$H$5$) is one of the most important reactive intermediates, as it is formed from the homolytic cleavage of a CH bond in benzene (C$6$H$6$), and hence it plays a central role in the combustion of fossil fuels that are typically rich in aromatics. We recently recorded the first high resolution infrared spectra of jet-cooled phenyl radical in the gas phase. This was obtained by direct absorption laser spectroscopy in a slit-jet discharge supersonic expansion of a phenyl halide precursor (C$6$H$5$X, $i.e.$~C$6$H$5$I and C$6$H$5$Br) diluted in a Neon/Helium gas mixture. We observed an A-type band, which arises from a fundamental excitation of the out-of-phase symmetric CH stretch ($\nu 19$). The unambiguous assignment of the rotational structure in this band to C$6$H$5$ is facilitated by comparing 2-line combination differences with the Fourier transform microwave (FTM) and direct absorption millimeter-wave (mm-wave) measurements of the ground state by McMahon~$et al.$ \textbf{590}, L61~(2003).}. A least-squares fit to an asymmetric top Hamiltonian of the rotationally-resolved vibrational band is done to determine upper-state rotational constants and a gas-phase band origin ($\nu 0$) of 3071.8904~(10)~cm$\mathrm{<mrow\; data-mjx-texclass="ORD">-1</mrow>}$. This is in very good agreement with the value of 3071~cm$\mathrm{<mrow\; data-mjx-texclass="ORD">-1</mrow>}$ for the out-of-phase symmetric CH stretch of phenyl reported by Friderichsen $et al.$ \textbf{123}, 1977~(2001).} from matrix isolation studies, which indicates a surprisingly small red shift due to the low-temperature argon environment.