One of my readers, Mark, asked me to explain what DXD is and why we’ve even heard of it.
Most of us know about DXD because of Octave Records and our penchant for DSD.
When we first started Octave Records we used the Sony Sonoma DSD system (Sonoma was originally developed by Sony and is now owned by Gus Skinas who was on their design team). Sonoma is only capable of DSD64—sometimes referred to as single rate DSD. This is a wonderful sounding format but can be bettered by a higher sample rate DSD system of which there is basically only one.
Pyramix by Merging Technologies.
Wikipedia explains: “Digital eXtreme Definition (DXD) is a digital audio format that originally was developed by Philips and Merging Technologies for editing high-resolution recordings recorded in Direct Stream Digital (DSD), the audio standard used on Super Audio CD (SACD). As the 1-bit DSD format used on SACD is not suitable for editing, alternative formats such as DXD or DSD-Wide must be used during the mastering stage. (DSD wide is a multi-bit DSD style format)
DXD was initially developed for the Merging Pyramix workstation and introduced in 2004. This combination meant that it was possible to record and edit directly in DXD, and that the sample only converts to DSD once before publishing to SACD. This offers a great advantage to the user as the noise created by converting DSD rises dramatically above 20 kHz, and more noise is added each time a signal is converted back to DSD during editing.”
Basically, DXD is PCM running at 8X the CD rate of 44.1kHz or 352kHz at 24 bits.
With that background, here’s an interesting twist that was told to me (and unverified). When Philips and Merging released Pyramix they touted their program was DSD based and capable of being fully edited and mixed. They further suggested that it was all in DSD. As the story goes, Sony freaked out and claimed foul, thus forcing Philips and Merging to rebrand their editing process as DXD so that people wouldn’t think it was DSD.
Merging is said to have claimed “BS” because DXD was sonically invisible to people and no difference could be told. The arguments went on and today PCM 352kHz (which is clearly not DSD) has its own name.
From my perspective, it’s clear to me that if you record in DSD and edit and mix in DXD, it is then sonically invisible. The opposite is definitely not true. Recording in DXD does not sound as good.
In any case, that should hopefully answer Mark’s question.
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