Seeking lower cost alternatives to Berkeley Audio Design Alpha USB converter


I am looking for a USB to optical audio converter.
The Alpha USB from Berkeley Audio Design is an external asynchronous USB to S/PDIF (or AES) interface. It's strictly a D to D converter accepting USB digital audio input and delivering digital audio output.
That's the type of product I'm looking for. However, at $1,895 the Berkeley Alpha USB is far more expensive than most similar products I've seen. Some of these products sell for less than $100.

I'm on a budget. Can anyone recommend one of the lower priced alternatives to the Alpha USB from Berkeley Audio Design?
lowoverdrive
I have had good success with the Matrix Audio SPDIF. Thumbs up for build quality, SQ and value

good luck
A network bridge may be what you are looking for. Ethernet is inherently low noise and is the best way to get bits from a computer to a DAC. I have a Pi2AES on a Raspberry Pi which produces very low levels of both noise and jitter, spanking much more expensive DDCs.
This may be useful: https://www.youtube.com/watch?v=Jvu_doQfAI0&t=152s&ab_channel=GoldenSound
@pengun - the video you shared just turned everything I thought I knew upside down. Fortunately, I didn't know that much. 

However, I can't immediately go down the Ethernet, I2S path. As it stands now, my two best DACs do not have I2S inputs. 

In another post you said: 

> Just got a Denafrips Ares II. Its really good, a wonderful source for any digital system. 

That doesn't appear to have an I2S input either. Did you switch DACs? What are you using now? 

I learned a lot from the video you shared. GoldenSound makes a compelling case for using Ethernet and I2S instead of USB (or Bluetooth aptX HD). I'm also fortunate that my entire place is wired with cat-6.

However, until I can acquire the hardware that will let me use I2S everywhere, GoldenSound's comments about using a Raspberry Pi 3b+ caught my attention. However, this video does not explain the basis for his recommendation. Is he saying to replace your PC with a Raspberry Pi 3b+? If so, is the reason simply to get rid of GPU and other noise from a complex system? I already have a simple but powerful headless PC running Linux. It uses a server mb without any GPU. I'm not sure a Raspberry Pi gives me any advantage, and the video doesn't explain things well enough for a beginner like me.

I’m going just to use RCA SPIDIF from the Pi2AES to my DAC. I should have my Cable in a day or two.

I’m building a SV-EQ1616D phono equalizer for my SKY 20, from Bob’s Devices, right now, because the damn Area II is kicking my analog’s butt right now. ;)
The output of your PC, via Ethernet, goes to the Raspberry Pi , which uses the Pi2AES to reclock and generate clean digital streams from the bits, that came over the Ethernet port.

It uses your PC and the Pi, this way, to feed your DAC this rather nice stream, rather than the much noisier USB stream which the DAC has to deal with normally.

You can if you want just hook a USB drive to the Pi and eliminate the PC entirely, but you will need a different OS on the Pi to handle that kind of setup.