Teclast/S:Flo2 RMAA measurements - part 1
Not a lot of iDevicers will have heard of the S:Flo or Teclast T51, but you should. It is a behemoth portable media player that looks like the iPod touch, but has few other similarities. Firstly, it uses two DAC chips to decode audio signals. I cannot comment on the direct effect of them as it would be silly to attribute the very good driving capability to something that doesn't have a single DAC analogue. The iBasso D4 portable headphone DAC/amp uses the same DAC chips but doesn't drive low Ω earphones as well.
The T51/S:Flo2 is good - to a point. It has a great line out (maybe even better than the iDevice - at least in certain areas), a very good headphone output, and very low levels of hiss. However, it is hamstrung by horrid navigation, a useless touchscreen, poor format support, and no gapless playback. There are faint artefacts in the signal at all volume levels, but are almost unnoticeable. When the screen is on, violent clicking invades the output signal - horrible. But, when the screen is off, the sound is quite good. I can't say I enjoy it 100%.
It drives earphones very well - very low distortion, very clean signal and has a smooth midsection. But, it just isn't that great till the LO is engaged. It bests my fun Sansa Fuze simply because it has a smoother, wider stereo image, but other than driving certain earphones better than the iPod touch, the actual sound signature isn't an improvement.
If all you do is use LO and an amp, I recommend this player 100%. Otherwise, it is good, but not great, especially as the HPO has a built-in low pass filter which slightly dulls or 'smooths' the signal. Here are RMAA results.
Firstly: Line out tests to the iBasso T3D, a very capable, very tiny headphone amplifier.
Signal to Noise ratio:
Total Harmonic Distortion: not always a bad thing
Intermodulation Distortion: the bad one!