Volumio’s RIVO+ Digital Transport Explained With A Hands-On View

Northern Italy is a powerhouse of manufacturing and industry. Whether it’s farming machinery, lifting equipment, computers or advanced electronics, this thriving area has quietly established a reputation for superb engineering for a century.

I mention this because in this feature, I’ve been learning about a high-end piece of digital audio equipment that’s been developed by a company in Florence. Founded in December 2013 by Michelangelo Guarise as something of a hobby, Volumio soon grew into a team of creative minds, engineers, music enthusiasts, and audiophiles, all united by the common mission to bring exceptional sound and design to a broader audience.

Volumio now manufactures a lineup of six high-end audio products including digital transports and digital-to-analog converters for audiophiles streaming digital music to high-end audio systems. Some of the company’s customers are audiophile fanatics who will leave no sonic stone unturned in their elusive pursuit of “perfect sound” that they may end up spending their lives chasing.

To get an idea of what Volumio’s products are capable of, I spent some time with its latest product, the RIVO+ digital transport. And what exactly is a digital transport? It’s a box of electronics that prepares digital source files ready to be decoded by a separate DAC. There is no DAC inside the RIVO+ and that’s because audiophiles often like to upgrade or switch DACs, depending on what they want to listen to.

The primary job of a digital transport is to marshal the digital source and pass them to a choice of input and output interfaces including methods like USB, HDMI, Google Cast, AirPlay and Bluetooth. It’s a versatile box of tricks that ensures a digital music source is as pristine and ready to be decoded as it’s possible to be. The RIVO+ does this by putting the binary audio signal through an electronic workout so it’s fit and ready to be digitally decoded.

Hand-built in Volumio’s Florence factory, the RIVO+ has a dedicated Application-Specific Integrated Circuit that Volumio has developed in-house. This is the brain of the RIVO+ which also features enhanced S/PDIF and AES-EBU outputs plus upgraded MEMS clocks in the device’s USB HUB IC. Don’t worry about all those acronyms if they make your eyes glaze over, suffice it to say that these components are there to deliver as pure a digital source as possible, ready for onward transmission to a DAC and hence to an amplifier where it will be output as audiophile-quality analog sound.

It’s hard to imagine how the clinical digital source could be tamed, expanded and opened by silicon chips and highly accurate digital clocks. Many people find digital music and audio to be cold and clinical. In fact, it’s one reason why there has been such a resurgence in vinyl and FM radio. But it’s not the fault of digital. There is nothing wrong with the format, just the way its prepared and decoded.

Many people know that digital music can be improved with a better-quality DAC. However, that’s only half the story. The way the music is assembled, checked and ordered prior to decoding can have a massive effect on the character and tone of the music. I wouldn’t have believed it until I began to delve into the research for this feature. My ears can hear the difference.

To shape and sculpt the digital signal, the RIVO+ incorporates a new and upgraded MEMS clock in the integrated circuit used for the device’s USB hub, the most common source for digital input and output. The MEMS clock processes and preserves the integrity of the digital audio signal as it leaves the unit. The result is an improved jitter stability that creates a as higher quality and more consistent audio output.

Jitter is the result of tiny timing variations and distortions in the digital source that can spoil or degrade the output signal. Cheaper digital transports and combined DACs often can’t control jitter to such a fine degree and that’s the difference between an average digital decoder and high-end devices like Volumio’s RIVO+.

The RIVO+ also includes an I2S/DSD-over-HDMI interface that can create an optimal sonic performance for some external DACs compared to using the more usual S/PDIF, AES-EBU and USB outputs. The dedicated ASIC used in the RIVO+ generates the S/PDIF and AES-EBU output signals for the unit, reducing strain on the main CPU. It’s this specialized integrated circuit that’s also responsible for the precision and lack of interference or jitter that could otherwise be introduced by the main processor.

Powering the dedicated ASIC is a high-quality Micro-Electro-Mechanical Systems clock, which provides stability and low-jitter timing reference for everything else in the RIVO+ to work from. Think of it as the conductor of a symphony orchestra. Alongside low-noise voltage regulators, this latest enhancement to Volumio’s RIVO+ is responsible for the signal purity and refinement of the signal that the unit produces.

The upgraded MEMS clocks used in the RIVO+’s USB HUB IC enhance the reclocking process and preserve signal integrity especially when the device is connected to its USB DAC port. This delivers jitter and frequency stability, reducing the unit’s susceptibility to temperature changes and aging so that the audio output from the device will always be of a consistently high quality over its lifetime.

To connect with the outside world, the RIVO+ offers a choice of Wi-Fi connectivity covering Wi-Fi 802.11a/b/g/n/ac, 2×2 MIMO with RSDB. This means it has a robust reception even in a building with fairly thick walls. Alternatively, the unit has a Gigabit Ethernet port which offers connectivity over wire without the need to setup a wireless network.

While the RIVO+ is a collection of premium components housed in a sturdy and slightly austere casing, the secret of this device is its firmware and software. The RIVO+ uses the latest version of Volumio OS—Volumio AI—that incorporates Supersearch, an AI-powered search function that optimizes music discovery so the user can always find the track you want across all your music sources.

The app at the heart of the RIVO+ lets the user select and curate their music choices. Volumio OS is also multi-room capable and that means it can work with other Volumio products around the home. With Google Cast and Apple AirPlay compatibility, users can also stream music to other units that work with those two standards.

The RIVO+ is also Roon Ready and works with TIDAL Connect, Spotify Connect, TIDAL, Qobuz, TuneIn, Shoutcast and many more sources. The device can handle almost any digital audio format including FLAC, DSD and MP3, making it a versatile way of bringing together all audio sources within the Volumio app which means everything can be controlled by a smartphone or tablet.

It’s probably fair to say that the Volumio RIVO+ isn’t the kind of device that’s going to appeal to a casual listener. Volumio makes no secret of its mission to serve the audiophile community and the prices of its products also reflect that. However, considering the amount of software and firmware development coupled with the premium components and the overall finish and sonic performance of the RIVO+, I wouldn’t say it’s an overpriced product. Whether most people need a RIVO+ is another matter but having listened to one for a couple of weeks, I think I do.

Pricing and Availability:

The Volumio RIVO+ is available now and costs $1,399 / £1,099 / €1.299 from Volumio.com.

Tech Specs:

• Digital Coaxial S/PDIF: Audio output up to PCM 192kHz/24-bit and DSD64 via DoP.
• Digital AES/EBU: Audio output up to to PCM 192kHz/24-bit and DSD64 via DoP.
• Digital I2S over HDMI output: Audio Output up to PCM 768kHz/32bit and DSD256
• USB output: Audio output up to PCM 768kHz/32bit and DSD256 (via USB DAC).
• USB DAC port: 1 x USB 2.0.
• USB: 1 x USB 3.0, 1x USB 2.0.
• LAN: Gigabit Ethernet 10/100/1000M.
• Wireless: Wi-Fi 802.11a/b/g/n/ac, 2X2 MIMO with RSDB.
• Bluetooth: 5.0
• Supported formats: DSD, WAV, FLAC, ALAC, AAC, Vorbis, MP3 and others.
• uPNP DLNA: Renderer with Open Home support.
• Supported services: Airplay via Shairport Sync, Spotify & Spotify Connect, TIDAL & TIDAL Connect, QOBUZ.
• Available plugins: Youtube, Squeezelite, Radio Paradise, Podcasts, Pandora, Fusion DSP, Roon Bridge, Soundcloud, Mixcloud.
• CPU: Amlogic S905D3, Quad Core 1.9GHz.
• RAM: 2GB DDR4.
• Internal storage: 16GB EMMC.
• Power supply: 5V, 3A.
• Weight: 2.25kg.
• Dimensions: 27 x 15 x 5cm.