Need to under stand Asynchronous USB


So I just got a Marantz ND 8006 Network CD player. Im using it as a network player and CD transport  and I output digital to my NAD M51 DAC. I’m using my IPad to stream TIDAL and that works tip top. However, it’s the USB inputs that concern me. I have a choice of a front connection and a rear USB DAC connection. 

Couple questions:

1. The USB DAC input is for a Mac or PC hook up, but is there any other way to use an input like this?  Does it have to come from a computer or can a USB hard drive work with an input like this?
2. More importantly the front USB input is NOT asynchronous.  I think they make a reclocker I can put in between the USB and the unit. My question is do they make a USB hard drive with a built in reclocker with a good amount of hard drive space?

this is all new to me, so any help would be appreciated. 
last_lemming
How much quality is lost streaming Tidal via wireless vs hardwired?  I read that wireless is not so good. 
It depends on the device. The old squeezebox touch's digital out was better wired vs wifi, but times have moved on, e.g. with the new Auralic stuff, wifi is reported to be equal if not preferred. You can just try comparing the two on your Marantz.
So I use tidal through my iPad to control the Marantz streaming. The Marantz is connected to my WiFi, so is the actual music data coming from my iPad or my computer in my room where the WiFi is located even though I have no app downloaded on my computer ?
...the Marantz is doing the playback; the iPad is just a remote control; your wifi network contains all the data being sent to and from the Tidal servers