External HD Changing the quality of the sound?


Hi everyone! It's my first thread i start in this community and i'm willing to go far in the journey of Hi-Fi audio :)
So i was wondering, is it real that if you put your audio file in an external hd it lower the quality on the outline?
I still don't have dac to test it so i wanted to be sure before putting my library in it, since my external hd is a 2tb and the one i have in my imac is a 500gb and is full...
Also, is it true that the type of connection used for my hd is changing the quality (usb 2.0, usb 3.0, firewire800)?
I know how it could affect it, i just want to know if it is all true?
freb03
a. Use a SSD for the main OS
b. OK to use an external drive for music
c. use a music player software that does memory cache-ing
I use a Westen Digital 2TB usb3 hard drive connected to my laptop with a dedicated usb3 connection. I use J Rivers Media Player 17, all files are ripped into flac and the sound is unbelievable. There is no loss of quality with an external hard drive. Make sure you set the software to use the memory cache.
Oh, if you are using a USB connection on your DAC, use a FW or Thunderbolt drive. If you are using a FW-SPDIF connection, use a USB DAC.
i have the G-Drive 2tb with firewire800 :)
I use itunes to manage my library (yes i know the bads about it, but i have too many music and the way it's displayed for me is easy to manage how to play my music)
So how can i set it to the memory cache? O_o
and it's better to use a different type of connection for my audio source than a dac or so it will take the power from it, isn't it right?