Sampling into Megahertz
Having tried 24-bit/88.2 kHz (and 96 kHz) tracks without being able to tell the difference from Red Book audio, we were starting to get skeptical about high-def audio. Still, we wanted to test the pinnacle of digital audio formats. We picked the most-sold album in history, Michael Jackson's Thriller.
We chose two formats: the exotic DVD-Audio (PCM at 24-bit/176.4 kHz) and the equally (if not more) exotic SACD (DSD64 at 1-bit/2.8224 MHz). The former is available from hdtracks.com for no less than $25. The latter is available from acousticsounds.com, also for $25.
To give you a better idea of the amount of data we're talking about, the uncompressed PCM version (24-bit/176.4 kHz, or 8467 Kb/s) is 2.5 GB, while the DSD64 version (1-bit/2.8224 MHz, or 5645 Kb/s) is 1.66 GB. That's just one album. From a bit rate perspective, DSD64 is essentially equivalent to 16-bit/176.4 kHz PCM, although that in and of itself says nothing about perceivable sound quality.
On paper, Realtek's ALC889 codec supports DSD. But we weren't able to get it working with foobar2000 due to a lack of an ASIO driver. Asus' Xonar Essence STX's DAC chip does support DSD, and Asus does supply a quality ASIO driver. However, Asus' DSP choice, the C-Media CMI8788, does not support DSD, breaking the chain. By design, the O2+ODAC does not support DSD. It's a driverless device that tops out at 24-bit/96 kHz PCM. That left us with Benchmark's DAC2 as the only device supporting DSD through foobar2000.
The catalog of SACDs is small, so a lack of support for this format is hardly a deal-breaker in any circumstance.
A Difficult Comparison
The DSD version of the album plays louder in foobar2000, creating a nightmare as we tried to volume-match. Unfortunately, foobar2000 does not support digital volume control of DSD files, and manually adjusting the DAC2 is an imprecise exercise at best. With that said, the tracks we listened to sounded extraordinarily similar, and we'd guess that they're from the same set of master tapes, though we don't know if the mixing is the same.
Given issues with volume matching and questions about mixing, we hesitate to generalize about DSD versus PCM, so please consider our observations specific to just these two recordings.
Both listeners felt that, while the two versions were enjoyable, the DSD-based copy was better overall. Listener B observed "greater musicality", while Listener A noticed a difference but had a harder time putting it into words, eventually concluding that the DSD version felt more natural.
- Turning The PC Into A True Hi-Fi Audio Platform
- Four Devices Tested: From $2000 Down To $2
- Benchmark DAC2 HGC
- JDS Labs O2+ODAC Combo
- Asus Xonar Essence STX
- Realtek ALC889
- Test Setup: Sennheiser HD 800 And AKG K 550 Headphones
- Test Setup: Volume Matching And Testing The Listener
- Test Setup: Cables, Software, And Tracks
- Test Setup: The Blind Testing Process
- Results: Dragonborn / Jeremy Soule
- Results: Soothe My Soul / Depeche Mode
- Results: Through The Fire And Flames / DragonForce
- Results: Get Lucky / Daft Punk
- Results: Symphonic Dances / Andante Con Moto / Rachmaninoff
- Bonus Test: DSD Versus PCM; Billie Jean / Michael Jackson's Thriller
- Why We Need To Test Low-Impedance Headphones Soon
- Why Audio Formats Above 16-Bit/44.1 kHz Don't Matter
- Anything Above $2 Buys More Features, Not Better Quality