The WM8804 and other I2S converter typical supply voltage equals 3.3V.
The I2S attenuators from ecdesigns i am using on my DAC module are designed for 5V TTL levels only.
So we need a buffer between the output of these 3.3V devices and the input of my DAC module
for a proper work, without canceling the advantages of the I2S attenuators.

If a I2S Converter has an onboard buffer like the Teralink X2, you don´t need this module.

If not, i have made a small "Ultra High Speed Buffer" Module, for the three data lines we need.
To get no interferences between the data lines, i made a discrete layout witch based on the fastest single buffer chip, the NC7SZ125 to prevent additional added jitter.

Specifications:
- 2mm pcb
- Immersion Gold
- green soldermask on both side
- 35µm copper weight
- Board size 50mm x 42mm