[FAQ] How can I turn off the Filter in the DAC or Upsampler?

The short answer is you cannot and you would not like the result if you could!
The dCS Ring DAC™ is an oversampling design, filtering is necessary to remove aliases produced by the oversampling process and Nyquist images produced by the conversion to analogue. These artefacts appear as mirror images of the audio band at higher frequencies, they cause unpleasant intermodulation effects if they are not removed. The digital conversion in the Upsampler generates aliases also, so these must be filtered out for the same reason.