Should be ok from a power standpoint. But driving the LCD-2 and especially the LCD-3s to their full potential really means more than just power. There's also different types of amps, Class A, AB, D and the way they deliver power is different. There's also the ability to supply enough current (which orthos love) when needed.
Its about the entire chain. Source --> DAC --> Amp --> Headphones. We'll leave cables out of this discussion . But for the "Summit-fi" level of headphones (like the LCD-2/3 or HD-800s) to really sound their best and let you hear what they can really do, one really has to ensure that the entire chain optimized.