Does Apple’s Core Audio resample AD/DA signal? – Page 2

OK – Robb’s experience piqued my curiosity!

I compared several 24-bit / 96 kHz WAV masters using the following:
• Logic Pro – Core Audio 24-bit / 96 kHz
• QuickTime Player – Core Audio 24-bit / 96 kHz
• Audirvana Studio – Buffer 5.0 GB, no signal processing added, r8brain deactivated, no leveling, integer mode enabled, 32-bit (integer) / 96 kHz PCM.

I used an RME ADI-2 DAC FS USB interface configured at 32-bit (integer) / 96 kHz.

I monitored using Meze Audio Empyrean headphones.

No other applications were running during the comparison.

The system was optimized for audio playback: Spotlight, Time Machine and Screen Saver were disabled, USB iDevice detection was disabled.

Logic Pro and QuickTime Player sounded identical.

Audirvana Studio offered a different presentation – there was an improvement in transient detail, image depth and stereo field precision – the audio was definitely enhanced.

I would hesitate to attribute this difference purely to the Core Audio subsystem – in my comparison Core Audio was not performing any sample rate conversion, or word length reduction.