aqua Formula xHD
Model: Formula xHD
Manufacturer: aqua acoustic quality
Our pure R2R Ladder Optologic DAC, fully-floating (isolated) FPGA
The Formula DAC is the first in aqua’s history to implement a proprietary resistor ladder conversion system we call Optologic.
The signals sent to the resistor ladders are generated by a proprietary digital circuit, programmed inside a FPGA (Field Programmable Gate Array).
The Formula has a sign-magnitude converter structure which requires not two but four 24-bit resistor banks; each one made with low tolerance discrete resistors.
In order to separate the sensitive analog circuits from the digital section, galvanic and magnetic isolation is implemented between the FPGA, and four branches of the R2R ladder converter.
This achieves complete isolation of the entire digital circuit - including clock - from the analogue section resulting in a clean, noiseless, ground plane.
It also serves a critical role in the differential management of the R2R ladders, creating perfect symmetry between the counter-phase halves. The result is the highest tonal contrast and naturalness.