Do you upsample?

Posted by: YanC on 16 July 2014

Most manufacturers don't make it clear of what DACs do.

Do they always upsample regardless of the input?

If yes, what do they upsample to?

Route 1

Use specialised software to auto-switch computer's output according to the sample rate of the track that's been played. There is merit on this when system software (like iTunes) will not autoswitch. But it's a little pointless if the DAC will upsample anyway(?!)

Route 2

Set the computer to always output at 192 kHz.

Use native software (iTunes, Media Player) or specialised software to upsample locally.

As the computer has vastly more processing power than the DAC, I've been trying route 2 with plain iTunes for the last day or so.

Happy so far regarding clarity of sound. Though I get the impression transients suffer a little. i.e. notes going from loud to quiet seem to be dropping faster than usual.

Need to live with it for a few days before I make up my mind.

Any threads on this?

(or thoughts?)

Posted on: 16 July 2014 by DavidDever

More importantly - ask if the DAC integer upsamples, or sample-rate converts the incoming input using a non-integer multiplier….

Posted on: 17 July 2014 by YanC

to answer my own question (in case someone else is wandering)

I reverted back to route 1 after a couple of days.

I felt there was a ringing sound upper mid frequencies, and overall a rounder sound to the music (less edge). It could potentially be that these were add ons of CoreAudio upsampling.

Hard to know. Felt a lot better sending the DAC actual data with Amarra Hifi) despite the glitches and latency of that app.

P.S.

Integer mode is disabled (according to BitPerfect), so it seems that my DAC does floating point sampling only.

Posted on: 17 July 2014 by YanC

and to quote Amarra manual

...we believe this [realtime up or downsampling] to be an audiophile no-no that results in non-bit-perfect, potentially inconsistent output. Ensure your DAC supports the desired sample rates natively and you should be all set.