Dolby® Upsamples & Apodizes TrueHD

Pictured (from left to right): Rhonda Wilson, Senior Member, Technical Staff, Products & Technology Group, Dolby Laboratories; Craig Eggers, Director, Content Creation and Playback, Home Theater Ecosystem, Dolby Laboratories; Poppy Crum, Senior Staff Scientist, Dolby Laboratories pose with some of the most recent titles using Dolby TrueHD with advanced 96k up sampling.

At 12 noon PST today, Dolby Laboratories, Inc. announced the availability of the first Blu-ray Discs™ premastered using Dolby® TrueHD with advanced 96k upsampling, The process, designed for use by studios, authoring houses, and mastering facilities, elevates playback performance of lossless audio on Blu-ray Disc™ by using the apodizing filter developed by Meridian.

Dolby TrueHD, whose white paper can be found here, has already been utilized to upgrade the sound in Greater China's release of The Flowers of War; the Joe Satriani concert film, Satchurated: Live in Montreal; and San Francisco Symphony at 100. The latter, a wonderful memento of San Francisco Symphony's Centennial Opening Night Gala, includes Michael Tilson Thomas conducting performances of Copland's Billy the Kid Ballet Suite, Mendelssohn's Violin Concerto in e with no less a fiddler than Itzhak Perlman, Britten's The Young Person's Guide to the Orchestra, and a multi-media version of Adams' thrilling Short Ride in a Fast Machine.

As Stereophile's representative at Dolby's two-day Fidelity Forum 2.0, where I rubbed shoulders with Rob Sabin, Editor-in-Chief of Stereophile's brother publication, Home Theater, and 19 other members of the international press, I had the opportunity to experience first-hand the difference that Dolby TrueHD makes. In an opening session, the overseer of the project, Dolby Labs' Craig Eggers, Director, Content Creation and Playback, Home Theater Ecosystem, explained that most studio content is recorded at 48kHz, whose preringing artifacts are audible and degrade sound. Even though manufacturers of better Blu-ray players often include upsamplers in their products to clean up the pre-ringing in 48kHz content and provide a smoother presentation, their solutions are, at best, only partial fixes.

Given that there are already multitudes of cheap Blu-ray players in people's homes that do an outstanding job of transmitting, if not amplifying every preringing artifact on a Blu-ray disc, the thought of trying to convince consumers to upgrade those under $100 players seemed futile. Instead, Dolby set out to develop a method by which they could improve Blu-ray sound in the discs themselves by upsampling those that had been recorded at a native 48kHz sample rate to 96kHz.

Their model was the advanced apodizing upsampling filter, employed in the Meridian Audio 808.2 CD player (now succeeded by the 808.3), which inspired John Atkinson to declare, "Without any hyperbole, ...I can say that the Meridian 808i.2 is the finest-sounding CD player I have yet heard."

Thanks to a process developed in part by Dolby scientist Rhonda Wilson, a DSP specialist formerly of Meridian, with 48kHz-sampled masters, the Dolby TrueHD media producer masks preringing artifacts introduced upstream by analog-to digital converters' linear-phase brickwall filters. Dolby TrueHD shifts the artifacts into postringing, which will be naturally masked.

Eggers summarizes the process thusly in Dolby's press release: "Lossless audio is a key distinguishing feature of Blu-ray content. All things being equal, you cannot improve on the quality of lossless audio coding; however, you can improve on the quality of the source PCM content prior to lossless encoding, and this is precisely what we have achieved with our advanced 96k upsampling technology....Studios and authoring facilities that implement Dolby TrueHD with advanced 96k upsampling can elevate the quality of PCM audio prior to lossless Dolby TrueHD encoding, ensuring that consumers get the very best audio performance possible from their Blu-ray playback systems."

A slide from Craig Eggers' presentation shows the benefits of the TrueHD upsampling filter, very much in line with what John Atkinson reported in his review of the Meridian 808.2 CD player

In a session presented by Dolby Labs' James Spezialy, Senior Application Engineer, Indirect Film Services, we heard side-by-side clips that compared Blu-ray's standard 48k sound with 96k Dolby TrueHD.

At the start of the comparison, Dolby distributed an "ear training" sheet that included tips on what to listen for. The list, which read like Audiophile 101, included "clarity and naturalness to sound, longer 'ring out' to reverb and ambience, consistent audible quality as high frequencies decay, better definition between instrumentation, and more natural-sounding dialogue with a less granular quality to voices."

As impressive as were the differences in clips from the Joe Satriani concert, Lost Bladesman, Batman Returns, Kung Fu Panda, and Flowers of War, the most telling comparison came via a 27 second, audio-only clip from the San Francisco Symphony. Heard via Bryston amplification, a Revel multi-channel loudspeaker set-up that included subwoofers, and generic cabling that I felt was the system's weak point, instrumental timbres sounded truer and more complete, with a more lifelike sense of natural reverberation and decay. In the switch to Dolby TrueHD 96k, an overall flatness of the 48k symphonic presentation ceded to a far more involving sense of air and space.

As someone who attended San Francisco Symphony's Centennial Gala, and knows the sound in Davies Symphony Hall from any number of premiere and not-so-premiere seats, I felt that Dolby TrueHD took me one step closer to being there. And while I may not wish to get any closer to Kung Fu Panda or his opponents, I'll gladly cuddle up to the sound of Perlman's violin or San Francisco Symphony's strings anytime I can. From what I've heard of Dolby TrueHD, the process succeeds in doing exactly what Dolby and Meridian intended.

Blu-ray discs mastered with the apodizing filter will be labeled "Advanced 96k Upsampling."

msardo's picture

If I read this correctly, I DO NOT need a new Blu*Ray player and also, I DO NOT even need a new firmware ugrade, etc.

Just a disc with the "Advanced 96k Upsampling" and I now have access to this new benefit/improvement - yes?

John Atkinson's picture

If I read this correctly, I DO NOT need a new Blu*Ray player and also, I DO NOT even need a new firmware ugrade, etc.

That's correct. The upsampled Blu-ray discs are 100% compatible with all players that can handle 96kHz-sampled soundtracks, which I believe is all of them.

John Atkinson

Editor, Stereophile

Bob Rapoport's picture

Thats correct, this is a software related upgrade, no need for upgrading HDMI to a higher version than today's standard v1.4.

Dolby TruHD and DTS MasterHD are the Holy Grail of high fidelity, offering bit for bit playback of the studio master recording with no compression for the first time in audio history. With its increased storage capacity of 50 Gb, Blu-ray is capable of playback at the same levels as the recording of the live performance, up to 30 dB more dynamic range than can be heard from a CD or a re-clocked and re-sampled CD.

The reason you reacted to the recording of the Symphony is the dynamic range you experienced, you remember how it sounded live and knew you were closer to that ideal than ever before. You were in fact listening to the actual recording of that live symphony as it was recorded, without compression. In order to hear the same thing at home, your Blu-ray player output must be connected via HDMI to a pre-pro or AVR with Dolby TruHD and DTS MasterHD processing. The Studios will not permit you to record this level of resolution but you can listen to it in all its glory if you have a system capable of abiding by the anti-piracy protocols, and of playing that loud and the privacy to do so. You can choose either LPCM 2.0 channel or either Dolby or DTS multi-channel sound, so for the 2 channel crowd stereo is still available too.

The Blu-ray Music catalog is growing. You heard the Joe Satriani show but imagine hearing Adele sing her first album live at Royal Albert Hall, or Stevie Wonder singing Sir Duke live in London in his new Blu-ray concert. To hear and see them live in HD at home is the best experience ever, even better than the live show in some ways. Madonna's show in Buenos Aries on Blu-ray is a new art form, a spectacular use of staging, sound, and video that is re-defining what a live show can be and resulted in her being selected for this years Super Bowl, nothing I have seen except the opening ceremony of the Beijing Olympics has been better technically.

These new Blu-ray concerts are the reason to get excited about music again. Watching and hearing Simon and Garfunkel perform 3 of their greatest hits on the Rock and Roll Hall of Fame 25th Anniversary Concert was an epiphany; singing The Boxer, Sounds of Silence, and Bridge Over Troubled Waters, they were old and grey, but the emotion between them and the quality of their voices left me stunned, those of us who grew up then remember what they meant to us all and the un-matched artistry they created.

Go to Amazon, click on Blu-ray, Music and Concerts, you will see hundreds of live shows, from AC/DC to Tony Bennett, Diane Krall to Chemical Bros, all your favorite music performed live by the world's greatest artists, played back without compression for the time in history. The clarity and detail are 50% better than the closest competing formats, DVD-A, SACD. As one who fought to hold on to the analog past, I can only say I was wrong. I didnt understand what the whole HDMI thing was about but now I do and can tell you the added investment in a properly equipped pre-pro or AVR with pre-outs offering the latest Dolby and DTS playback codecs was worth it, by far the best upgrade we've ever been offered.

Regards, Bob

Morten Lindberg's picture

I'm afraid this approach will serve as a sleeping pillow for the content providers, relying on up-sampling rather than recording true HiRes in production ...

JasonVSerinus's picture

I hear your concern, Morten. The reality is that most movie and theatrical outfits record in 48/24. I don't think they're about to upgrade all their mastering and editing equipment. For them, Dolby TrueHD offers a definite advance in sound quality without additional cost. (Dolby supplies the service without charge).

Companies such as Naxos also recorded many of their earlier projects in less than 96/24; some of their future Blu-ray issues may benefit from Dolby TrueHD. Operations driven by more enlightened engineers, such as 2L (yourself) and AIX (Mark Waldrep), already record with high sampling rates; their Blu-ray issues have no need of Dolby TrueHD.

Dr. AIX's picture

The whole issue of natively recorded HD-Audio or "processed" to higher sound through various techniques including the Dolby process bring into question the bigger issue of "audio provenance". As long as companies clearly identify the recording stages in their marketing efforts and don't try to claim something is better than it really is...then cool.

What is not appreciated is the continuing claims that older standard definition recordings simply transferred to 96/24 or "processed" with apodizing filterings are not "HD" tracks at all...and simply diminish the chances that real HD-Audio will succeed.