We report an intracavity ring laser constructed using two parallel directional fiber couplers that generates up to sixth-order cascaded Stokes. Pumping with 1117 nm results in a Raman fiber laser operating at 1572 nm. Using 4.2-W pump power and a fiber Bragg grating at 1117 nm to reflect the residual pump, we obtain an output power of 0.65 W, and hence near 15% conversion efficiency. The linewidths of the dual-coupler laser are significantly narrower than those of the single-coupler laser. This enhanced wavelength selectivity is attributed to the significant increase in the contrast or the finesse of compound ring resonators constructed with two parallel couplers.