mechanical resonance. However, Fig. \[feedforward\]d also illustrates that the noise power off resonance increases with increasing $w$. At $w=1$, the background noise receives equal contributions from the optical measurement noise and fed-forward noise from the microwave measurement chain; for $w>1$ the noise introduced by feedforward will dominate off-resonance while the thermal noise around $f_m$ continues to decrease.

For reporting noise performance of the converter, the relevant metric is noise referred to converter input, which can be calculated from the output noise on resonance by dividing by the apparent converter efficiency, $\mathcal{A}\cdot\eta$. One can then consider an added feedforward noise at converter input (right side of Fig. \[feedforward\]d), reflecting how much the observed noise exceeds the amount due to the imperfect measurement chains and vacuum noise. Feedforward with $w=1.6$ effectively adds $N_\mathrm{add}=38~\mathrm{photons}$ of noise to the converter input, the majority of which is fed-forward microwave measurement noise.

It is interesting to make a comparison between feedforward operation and laser cooling (electro/optomechanical damping) of the mechanical oscillator. As shown in Fig. \[feedforward\]e, increasing the total damping, $\Gamma_\mathrm{T}$, while maintaining matching, $\Gamma_\mathrm{e} \approx \Gamma_\mathrm{o}$, improves noise performance while increasing bandwidth. Damping rates are limited by laser-induced heating of the superconductor and LC parameter 