Audiopraise VanityPRO HDMI Extractor

REVIEW
by Andrew Quint
Feb 13, 2024

You could say that the third age of multichannel music is upon us. The first, of course, was the Quadraphonic era that began its run in the late 1960s and witnessed the availability of four-channel records and tapes. But the technology was flawed and, to the average consumer, seemed overly complex and expensive. It was gone within a decade. In the mid-70s, Dolby Laboratories introduced analog surround-sound systems to theaters. When movies finally became available to watch at home, both visual and sonic quality advanced with a series of formats including Betamax (1975) and VHS (1977) tape, Laserdisc (1982), DVD (1995), and, finally, Blu-ray (2006). SACD (1999) and DVD-Audio (2000), riding the home-theater wave, initiated a second age of multichannel music, which also failed to gain much traction with an audiophile constituency. A more general flight from physical media had an impact, as well. In 2012, the first Dolby Atmos-encoded movie was released (Pixar’s Brave), and, for whatever reason, audiophiles seem to be much more interested in what’s called immersive audio. In addition to music-only Blu-ray discs offering “object based” spatiality, thousands of Dolby Atmos tracks are currently available for streaming from Apple Music, Tidal, and Amazon Music.

So, great, right? Multichannel music is once again in its ascendency and perhaps this time with more audiophiles interested—except for one technical drawback that many feel significantly compromises audio quality. That’s the High-Definition Multimedia Interface, better known as HDMI, a proprietary transmitter/receiver protocol that transmits audio and video data from a source to DACs. Consumers have been told that HDMI is great for video, which is true, and that it’s also the “best” interface to carry music, which isn’t. There are two primary problems with HDMI, when it comes to audio. The first is the poor quality of the clock recovered from the data stream that’s responsible for a substantial amount of phase noise; the second is that HDMI is very sensitive to factors like electromagnetic interference, cabling, and ground loops. There’s a consensus among digital engineers that other “digital audio transport methods”—SPDIF, AES/EBU, and USB—sound better. But alternatives for consumers, especially when multichannel is involved, aren’t widely available. HDMI is ubiquitous.

The Czech company Audiopraise was launched in 2014; before that, this small group of audiophile engineers worked as for-hire designer/consultants. An early effort was the Vanity⁹³module, a circuit board sold to consumers to be installed into the then wildly popular Oppo BDP-93 disc player to improve digital performance, especially DSD-to-PCM conversion. (I reviewed the Vanity⁹³ more than a decade ago, in TAS 228.) The first Audiopraise product marketed under the company’s name was the CZAP DAC. Pavel Valousek, one of the Audiopraise principals and the company’s de facto spokesman, described the CZAP to me as “a collection of all our IP, design techniques, algorithms, and circuits, which are still being used in various combinations in our other products and in our consultancy business.”

Valousek and his colleagues have taken the issues with HDMI seriously and, not surprisingly, have identified the audible problems as relating to jitter. Basically, the HDMI geometry consists of multiple conductors that include an elaborate TMDS (transition-minimized differential signaling) clock channel, as well as separate paths for audio, video, and auxiliary data. In standard applications, the audio clock at the HDMI receiver end is derived from the TMDS clock. The process of generating the audio clocks (determining the audio sample rate and generating the necessary clocks from the TMDS clock) must be very precise to avoid introducing timing errors. Audiopraise throws out the TMDS clock and instead use the incoming data rate to generate a new and extremely stable audio clock with the help of a pair of custom-made audio oscillators plus “a clever control algorithm.” Measured jitter is reduced to extremely low levels. (I recommend reading a highly understandable “white paper” authored by Valousek and his associates that details the experiments done and measurements taken to develop the VanityPRO’s tech: audiopraise.com/projects/internal/vanitypro/hdmi-audio-jitter/.)

The VanityPRO takes in digital audio on HDMI and outputs up to four two-channel digital data streams in the SPDIF or AES/EBU formats. The HDMI signal that comes into the VanityPRO is scrupulously isolated from the audio areas of the component by a “dielectric barrier” that limits the amount of electromagnetic noise that can pollute the audio and newly created clock circuits. Included are two Jameco power supplies, one for the HDMI part of the extractor and one for the audio domain. By the time you read this, Audiopraise promises to have introduced a linear power supply for the VanityPRO that matches the product in appearance.

The VanityPRO HDMI extractor is a compact component weighing about two pounds; its black (or silver) metal case measures 10.5″ x 2.6″ x 7.2″. In front is a single rotary/push-button knob that provides complete operability of the device, as well as an LED status indicator light and a 57mm x 43mm LCD screen. Around back, the appearance differs according to which output board has been ordered. Multichannel listeners will find four digital connectors for a total of eight channels via either AES/EBU (XLR) or SPDIF (RCA or BNC). There’s also a stereo version that has one of each of those digital outputs, plus TosLink. To the far right and left of the rear panel are ports for the two supplied external power supplies, the HDMI input, an HDMI output (for video pass-through) and two word-clock outputs (44.1kHz to 192kHz and 22.5792MHz/24.576MHz) that allow for clock synchronization with downstream devices such as a DAC.

Navigation around the ten pages of menus quickly becomes intuitive. The Home page shows what the VanityPRO is receiving via its HDMI input—PCM vs. DSD, sampling rate, bit resolution, whether the incoming signal is active (Run or Stop), and the number of channels coming in. It also allows for adjusting volume on an arbitrary scale from zero to 100. An Audio Setup page lets one establish parameters for DSD-to-PCM conversion with Audiopraise’s own proprietary algorithm; DoP can be enabled if that’s what your DAC wants. The user has a choice of four conversion filters and DSD/PCM level-matching can be selected. There are also menus for speaker setup and setting channel levels in 0.5dB increments (maximum attenuation is -7.5dB). Additional pages include HDMI setup (a “repeater” option lets the original incoming HDMI stream pass through as is), EDID setup (video parameters and speaker layout), system setup (screen brightness, clock functionality, factory reset), HDMI AV information, and a screen with eight audio-level meters for quick confirmation of signal input. Finally, there’s a very busy system status screen that requires better-than-average vision or a magnifying glass to be of much use. (I went with the second alternative.)

For this review, I requested the multichannel AES/EBU version of the VanityPRO. To get a handle on the component’s impact on an incoming TDMS data stream, I first used a two-channel source to send signal to my aging but dependable Anthem D2v preamp/processor, since far fewer variables would be involved when making comparisons. The Anthem has a single AES/EBU stereo digital input plus plenty of HDMI inputs. I used identical AudioQuest Chocolate HDMI cables from a Sony X1100ES disc player to either the VanityPRO or directly to the Anthem; a Wireworld Platinum Starlight AES/EBU cable connected the Audiopraise to the Anthem. Comparing “native” HDMI to the data stream leaving the VanityPRO was as easy as switching the AQ HDMI cable of the Sony player and changing the input on the Anthem. The Anthem connected with Siltech Classic Legend 880i balanced interconnects to Tidal Ferios amplifiers driving Magico M2s via Siltech 880L speaker cables.

Listening to familiar reference recordings, from CD and SACD, demonstrated more substantial differences than anticipated between the native HDMI input and the extracted one. With the exquisite readings of the two Brahms clarinet sonatas by Anthony McGill and Gloria Chien on the Cedille label, I heard a more seamless joining of the chalumeau (low), clarion (middle) and altissimo (high) registers of the clarinet. The sound was perceived as emanating from a single object, rather than three. Subtle inflections of the clarinet’s dynamic level and tone color were more easily appreciated, and Brahms’ characteristically dense left-hand piano writing was clearer. On the Haitink/Concertgebouw version of Shostakovich’s Symphony No. 15, a recording I return to for pretty much every review I write, the opening glockenspiel notes were nicely differentiated in terms of exactly how hard the percussionist was striking the bells. The active bass part on “This Town,” the opening track on Patricia Barber’s Clique, was more evenly reproduced in my room than is often the case, and the singer’s voice was richly characterized. It was hard to imagine the title track on The Big Phat Band’s Act Your Age album having more coherence at enthusiastic playback levels. “Too Proud,” from Joe Harley’s BluesQuest SACD sampler, which headlines vocalist “Mighty” Sam McClain, had startling dynamics and the singer’s anguished vocal was as gripping as I’ve ever heard it—and I’ve heard it a hundred times.

With the benefits of the HDMI extraction process apparent, I picked out favorite multichannel selections to hear in surround. This time, the tracks were played off my NAS with a Baetis Reference 3 server. For a multichannel DAC, I borrowed an Okto Research dac8PRO, which has four two-channel AES/EBU digital inputs (I needed only three) and eight XLR analog outputs (I required six, of course, for 5.1 playback). Amplification for the center and surround channels was provided by three Pass XA 60.8s. The additional speakers were Magicos—an S3 Mk2 for the center channel, a pair of S1 Mk2s for the surrounds, and an S Sub.

I’ve never enjoyed a multichannel presentation in my room more than I did with the Audiopraise/Okto combination. Paavo Järvi’s PentaTone recording of Stravinsky’s L’histoire du soldat comfortably distanced the nine players from one another on the large stage of a German broadcast hall. Each player clearly occupied his or her unique location yet seemed to be breathing the same air as the others. Scaling of the disparate instruments was ideal. On “LTMBBQ” from jazz pianist Wayne Horvitz’s Sweeter Than the Day, it’s not always easy to hear that the guitar doubles keyboard for the “head” played at the beginning and end of the tune; it was never more evident than with the VanityPRO in the audio path.

There is one fly in the ointment. At least for now, the VanityPRO cannot be used with Dolby Atmos or certain other immersive formats such as DTS:X. Pavel Valousek says: “The VanityPRO can pass through raw Atmos data (packed in Dolby Digital Plus or TrueHD), but there is no device such as a DAC or processor that would be able to take that digital audio, reassemble the compressed data, and decode Atmos. Handling the compressed multichannel formats is a completely different ballgame, and we may look into this in the future. That would mean getting into the AV receiver domain.”

The rise of object-based multichannel audio has been impressive but the primacy of this approach for multichannel music is far from certain at this point. If you’ve been into surround sound in a big way and have a large library of discrete multichannel music, the Audiopraise product effectively addresses the shortcomings of the HDMI interface—a factor that has limited the ultimate quality of DSD and high-rate PCM playback for critical listeners, and the cost is reasonable. If you have a suitable multichannel DAC (or would consider getting one), you should give the VanityPRO strong consideration. It delivers on its promise.

Specs & Pricing

Product type: 8-channel HDMI extractor
Inputs: HDMI x2 (one is video pass-through)
Outputs: Choice of four two-channel AES (XLR), SPDIF (RCA), or SPDIF (BNC)
Supported sampling rates: 44.1kHz/88.2kHz/96kHz/ 176.4kHz/192kHz
Dimensions: 10.5″ x 2.6″ x 7.2″
Weight: 1 kg (2.2 lbs.)
Price: $1899