44.1khz to 48khz conversion

I’m curious about something.

My audio interface is an RME Fireface UFX set to 48khz and Nuendo v.5.5.3 is also set to 48khz.

I’ve connected a 44.1 S/PDIF signal from a Roland V-drum to the 48khz AES-EBU input on the UFX.

When the audio arrives in Nuendo it is recorded at 48khz (which is what I want), but is the conversion from 44.1 to 48 being done by the UFX or Nuendo?

Why would you not record at 44.1k if that’s what you’re receiving?

If there is conversion I’d guess it’s done by the RME on input. I’m curious how this all works though clocking wise…

Because I want to record everything at 48khz/24-bit for film and audio. Plus the fact that I also use two MR816’s linked via Adat to the UFX and they are not capable of auto-detecting the sample rate (they have to be manual changed using a firewire cable), so it is easier to standardize at a single sample rate.

I see. Well my guess is that it’s the RME that’s doing it.

Quite odd that. I would not expect the FF which is set to be clock master at 48k (I presume) to be able to handle incoming 44.1k without glitching. Steadyclock is very clever, but RME don’t claim it can do on-the-fly SRC (unless I’m missing it)

What does the Fireface utility say?

I wonder if the FF is in fact clocking to the incoming 44.1, which would mean Nuendo is running at 44.1, which would probably cause at least an error message or possibly the whole system running 10% slow…

Nuendo is definitely running at 48khz 24-bit and the resultant recorded track is also at 48/24 if I look at it in the Pool.

I’m not complaining - I couldn’t be happier, but it would be interesting to know how this is happening.