I guess for this application you don't need better distortion because the consumer won't be able to hear it. SNR is something they would hear and complain about if they were using the product in a quiet environment. If the SNR was low the user would notice it at lower volume settings.
Hello, Hughston. My name is Robert Rich, and I'm in the analog communications group at TI. I've got an answer to your question.
The TLV320DAC3202 was designed for portable headset applications like media players, where typical average power levels are 0.1 to 2mW for a 32 ohm headset. Headset loads range between 16 to 150 ohms, and OEMs add a series resistor between the output of the headset amplifier and the load for acoustic safety reasons. The large swing of 1VRMS at the ball of the IC guarantees adequate power to the load even when the series resistor is added.
So this chip will put out 1 Vrms but the THD curves are show for 10 to 15 mW and the THD is listed at 68 dB for 20 mW into 16 ohms. I think I would rather see what the THD numbers are for higher drive levels. I wonder how good the part really has to be for a consumer audio product? The SNR looks good enough but maybe not the THD.