For sale is a Wavelength cosecant DAC V3, with the Numerator board. The Cosecant connects the USB controller to a DAC module connector. The USB firmware to run that DAC nodule resides there so each module has it's own developed code. The output of the module connector is sent directly to the 6GM8/ECC86 dual triode output tube, which drives the transformer coupled output. The Cosecant has an external power supply with an IEC input, this isolates the DAC and it's output transformers. Any additional is available on Wavelength Audio's web site. No reasonable offer refused.