No change in SQ from the Amp in my experience, just bump you the signal level making it louder. Connected to my HD800S the 150 volume level on the AK320 unamp, becomes like 100 with the AMP in High Power mode.
Comparing with the MOJO, well they are different signatures. The AK320 has more emphasis in mid range, while the mojo is little more sparkly, both DACs I like them so much.
Amp may help the output impedance. AK daps have issues with some low impedance Iems so maybe the amp would help that. For instance the ak320 output impedance is 2ohm and the chord Hugo is .075 ohm-better for Iems under 16 ohm. Can't find an output impedance listing for the ak380 external amp though.
Not really. The AKM4490 DAC is much more capable than the Cirrus Logic used in the AK240, plus you have much better accessories integration with the amp, ripper, and recorder. The volume knob is much better too.
I was so excited about it, I thought I could get kickass AK design with a good UI, reasonable price, excellent build, and good sound with that AKM and those femtos, but boy was I disappointed. The 300 sounded really bad to my ears. It was muddy and murky, the ak240 is way better technically to my ears.
I don't think it's fair to judge by the dac chip used. My soundaware m1 pro studio edition has a single cirrus chip, but most people who have heard it feel that it's more transparent and resolving than most daps except perhaps the lotoo paw gold, the ak380 copper and the questyle qp-1r perhaps.
I see you have posted this question in this forum and the AK380 forum?
If you are dragging files from the SD card in the AK to the AK internal memory, then yes, it will take a long time as all the data will being moved back to the PC and out to the AK again. The USB link for the SD card is slow in any case, and and this will make it even slower.
If you can, it would be faster to take the SD card out of the AK and mount it directly in your PC/Mac and then do the copy. That way only writes to the AK internal memory will take place. Internal memory access is much faster than access to the AK SD card