The better amp?

joser, god knows. With any op amp it depends on the application. Most audio aficionados are going to say discrete components are always best. All I can tell you is that you will have to listen to examples and decide on your own.   

sorry, what means discrete in amps? thanks

Ok, I already read it, but according to what I read in the description of Texas Instruments for the TPA6120A2 is this: 

In applications requiring a high-power output, very high fidelity headphone amplifier, the TPA6120A2 replaces a costly discrete design and allows music, not the amplifier, to be heard. The TPA6120A2’s current-feedback AB amplifier architecture delivers high bandwidth, extremely low noise, and up to 128dB of dynamic range.

Three key features make current-feedback amplifiers outstanding for audio. The first feature is the high slew rate that prevents odd order distortion anomalies. The second feature is current-on-demand at the output that enables the amplifier to respond quickly and linearly when necessary without risk of output distortion. When large amounts of output power are suddenly needed, the amplifier can respond extremely quickly without raising the noise floor of the system and degrading the signal-to-noise ratio. The third feature is the gain-independent frequency response that allows the full bandwidth of the amplifier to be used over a wide range of gain settings.

joser - TPA6120A2 is a monolothic "chip" type op amp headphone driver.  Like mijostyn said, discrete analog stages will almost always sound better than monotholic op amps.  Also, Roland is driven by a wal-wart switching power supply, which is never as good as linear power supply (like in Emotiva). I have said this in your other thread.