I have a couple of set ups and I was wondering if people prefer to use Roon to upsample, or let their DAC do it, if it supports doing so.
I do it through Roon but having tried both Roon and the DAC upsampling I didn’t hear any difference. As always YMMV so let your ears be the judge.
Well it depends entirely on the dac, surely?..
Most of DACs in the market already have built-in ‘oversampling’ by default and cannot be disabled. Though some DACs have built-in hardware ‘upsampling’, software up-sampling can be more flexible with different type of digital filters, hence one can tailor the sound to your liking.
The real difference comes when a particular DAC can bypass its over-sampling digital filter completely and use software upsampling like Roon 1.3 or HQP. Especially converting 44.1k to DSD makes a lot of difference.
You seem to have missed the obvious fact that if you upsample in Roon to the DAC’s native frequency, the DAC’s built-in oversampling which supposedly “cannot be disabled” will no longer being activated.
That’s provided you know what is the maximum native frequency the DAC it can handle, for instance, most off selves DACs chip max out to 352.8k/384k, one need to up-sample to this sample rate to avoid the hardware over-sampling digital filter kick in, though you still have the last digital filter to filter off anything above the 352.8k/384k. Some DACs in the market can over-sample higher like 705.6k/768k or even higher, than one has to up-sample even higher than 352.8k/384k to ensure hardware over-sampling doesn’t kick in.
My argument of having over-sampling bypass in the DAC itself allows any sample frequencies to the max to pass through it without having to worry whether the hardware over-sampling in the DAC kick in or not. We want the DAC to do strictly a digital to analogue conversion with a gentle LPF, while up-sampling is done in the software like Roon and HQ Player.