SRC: Who’s doing it?

James Hardiman

Antoine wrote:

Hi Hi Bob, Suppose I listen to a Quicktime (or VLC etc…) audio file (or vidéo) that has 44.1/16 sampling and my converters are set to 88.2/24, « who » is making the upconversion on the fly?
The computer or the converter?



Dear Antoine:

Hi, Antoine. The computer is doing the upsampling. There are plenty of drivers and players which will change the sample rate of your interface for you that avoid this issue. Apparently VLC is not one of them. I know that Quicktime is not built to do that. Nor is iTunes. But a number of high end third party music players will control the interface for you.

Best wishes,



Hi Bob,

Thanks for your reply.
It is bizarre…
As long as the upsampling is a direct multiple (let’s say a 44.1 file played at 88.2), it sounds excellent. Not so if the file is 44.1 and the interface at 96.
Thanks again!
A great day to you and Mary!
Dear Antoine:
The answer is simple: the computer’s upsampling algorithm is not a very good one. I don’t expect Apple (or microsoft) to do a better job. Everything is geared to cheap built-in DACs, 44.1 kHz reproduction, and consumer comfort. If you want good reproduction, move to a high quality dedicated media player.Best wishes, Bob