This actually applies to the MasterQ as well...

If I use either MC or MQ in FAT mode on a 44 or 48k file, is it identical to using normal mode on a 88 or 96k file? IOW, is it a "waste of time" to upsample a 44 or 48k file to 88 or 96k before processing?

Also, does VW double sample? In the end, I would rather do the limiting (VW) at the higher Fs (88 or 96k)...

Hello,

Upsampling by integet multiplier (eg 2x) with high quality convertion algorithm will give you similar results to those with a FAT algorithm.

The PSP VW is not using any double sampling. It would actually not be a brick wall limiter in a double sampled mode but we are considering it as an option for future versions.

Regards,