Asynchronous USB vs. SPDIF with regard to DAC upgrade

Also if you follow the general discourse, there seems to be a consensus that computers (as a streamer) are bad and Wi-Fi is bad.  When I bought my first Lumin some years ago at Upscale Audio, they explained to me that Lumin was somewhat unusual in that they believed it was best to get the computer away from the DAC by networking the Lumin (which like the Weiss many of their models are also a streamer/DAC), putting the music files somewhere else on the network.  This can use a simple computer, since whether using a switch or Wi-Fi, the DAC then takes the job of processing the bits (as you mention above regarding USB), including clocking.  I think there’s a lot to be said for this model.  Streamers have become so expensive because they -are- computers.  They now have fancy power supplies, and all kinds of other tech to minimize the damage of having a computer nearby the DAC.  Networking it takes care of a lot or most of that.  So you can use a computer in place of a dedicated streamer, and I would argue, aside from possible dropouts, you can use Wi-Fi here as well since the DAC/streamer is processing and buffering the bits, as long as they get to it.  
 

So as an example use case, you can take an old laptop or desktop you have laying around running Roon (or other software) and holding your music files, attach it via Ethernet to your router or itself via Wi-Fi,  and plug in your streamer/DAC via Ethernet also, whether hardwired or Wi-Fi, and you never need a file server/streamer (like an Aurender).  Yes, people can argue what the best sounding setups are based on many variables, but if you don’t want a separate DAC and audiophile-grade server/streamer (many of which you’re also paying for their software, like aurender or Innuos), this is a workable alternative, and not necessarily a sonic compromise.  

+1 @tubeguy80 

the answer to the OP is “it depends”.  Theory will only get you so far.  I’ve heard many DACs where usb was either the best or the worst option.  And does anyone make asynchronous usb anymore?

This response is directed to audphile1. You mentioned in this thread that the Berkely Alpha Series 3 Dac does not have a network card. I thought a network card is found in a streamer and not a stand alone Dac. If I am incorrect would appreciate the correct information so any buying decision that I may make will be based on correct assumptions.  Thank you. 

@kjl1065 

There are different categories for these digital sources.
1. streamers with built in DACs:  typically a single box solution geared towards convenience with somewhat compromised DAC performance. These units feature native streaming software. Examples include Lumin D and Aurender A lines

2. DACs with built in network cards that allow a user to leverage these units as Roon endpoints and or Qobuz connect or Tidal connect streaming devices, with primary focus still being the DAC. 
 

There are different tiers for each category. A very large portion of high end DACs include network cards of various quality. Examples include Mola Mola Tambaqui, Playback Designs MPD-6, Weiss, Meitner MA3i, EMM Labs DA2i, Bricasti and dCS DACs. 
Some of these DACs have excellent design and implementation for these in-built streaming cards. 
In my system the Meitner MA3i eliminated the need for Aurender N200 and a high quality USB cable that I used it with to feed the DAC. 
A good Ethernet cable into Meitner is all it takes. I am using it as a Roon endpoint. 
 

Hope the explanation and examples I provided are helpful. 
 

Now…going back to your plan with Berkeley that will require a top notch clock implementation in the streamer due to its lack of USB and network card, will demand you add a streamer on the level of Aurender N20. 
Only you can be the judge if a streamer in this configuration is an added value. That’s why I and everyone else is suggesting you try different DACs including those with built in network cards. And compare using different configurations.