I'd love to buy one, but not sure where I'd use it. Perhaps a dap for the car
Reply rephrased as per compliance to moderator instructions. Note that the original reply from writer's own perspective is more along the lines of "too familiar" in the sense that that is the manner by which conversations with his friends carry on, with some sarcasm and exaggeration, and not in any way nor should be construed as demeaning, hostile, or "trolling."
A few things have to be considered in that case:
I.
Financial Angle
A very general financial advice would be that if the consumer is unsure of what use a product will serve, it may be best to avoid the purchase and redirect the funds elsewhere. In this case it might be redundant for one function while not performing other functions, such as when your smartphone suffices as a portable player with an efficient IEM, which also allows for important calls to interrupt the music as opposed to not hearing it ring or not feeling it vibrate while listening through a separate device.
II.
Ergonomic Issues
Using such a DAP in a car entails ergonomic issues, as in this scenario: picking up the DAP with a long cable on it in order to manipulate the interface, driver's eyes far off the road and even the red light. By contrast a car's receiver is located and designed such that the driver can manipulate its controls with relative ease out of the corner of one's eye while watching the traffic light on the other edge of one's field of vision. Some mounting options will address the eye and hand issues, but note the likelihood of the DAP falling out of such a mount. At the same time, most current automobiles as they come from the factory are no longer restricted to CDs and DVDs, and may function as a host to access multimedia content stored an Android, iOS, or iTunes device as well as other storage mediums, such as USB drives; alternately, aftermarket solutions that include such a feature can be had for less than $200 - not much more than the DAP in question, the use of which results in the concerns raised above.
III.
Structural Issues that affect audio reproduction in automobile cabins
SQ benefits are problematic due to:
a. The primary issue in a car being the non-central driver's seat in all non-Formula cars barring the McLaren F1 and the Lamborghini Egoista, which results in non-equidistant positions* for the tweeters and midwoofers relative to the driver's ears. Such a seating configuration is contrary to how one sits at home between two speakers,* or how a human skull is still generally symmetrical enough as far as headphone fit and driver distance from the ear drums is concerned.
b. This non-equidistant setting causes time alignment issues that affects imaging as well as
frequency response. The difference is in microseconds, however can result in such problems as hollow and/or too-soft bass (when you hear the same note which comes out of both the midwoofer and the subwoofer too many microseconds apart), or sibilance (when you hear the same cymbal or vocal note from the midwoofer and tweeter microseconds apart). In terms of imaging, the center of the image has a bias to be pulled towards the nearer speakers, hence the vocals are off-center and towards the listener's side, as opposed to the very center of the dashboard.**
c. The higher quality DAC, itself subject to debate regarding differences from one (properly implemented) chip to another, and output stage of a DAP like the X1 will not be able to overcome the above structural reality that results in an issue that affects the fundamentals of audio reproduction, and even with regards to frequency response (if at all, as again there is the matter of the debate regarding differences between digital sources) of a DAP over any car receiver, is again being reshaped by this simple time alignment problem, and while primarily the cause of most issues with listening in a car's cabin is only the first among many.**
*
Visual representation of problem described in Section III-a. Note the the equidistant seating arrangement at home vs the color coded, varying path lengths from the driver's head to each transducer inside the automobile cabin.
**Note that DSPs found in some car audio processors have time alignment functions that add delay to the speakers to synchronize with the farthest one, which comes at its own cost of fixing the imaging and frequency response for only one seat in the entire car (though not necessarily making it much worse at the other seats). This also makes it possible for the driver (or the passenger seat, depending on the tuning of the time alignment settings) to be able to hear the reproduction image along the dashboard with a clear center image, primarily the main vocals, in the physical center of the dashboard.
IV. In sum,
any SQ gain will still be hampered by the inherent issues of listening in a car's cabin, and the quality of the usual audio hardware (DAC, amplification, to a much lesser extent the speakers) do not matter as much as fixing the time alignment issue. On top of which are ergonomic issues that you would preferably avoid, given traffic laws that regulate mobile phone use (as specifically stated in some laws, although a more general term may be in use in others) drafted with public safety in mind, and the fact that in this situation $100 will be spent for this sole purpose from which issues either arise or are not adequately addressed by said expenditure.