Digital-to-analog converters have become stunningly sophisticated over the past 30 years, evolving from small circuits inside early CD players to stand-alone components with advanced capabilities and performance unimaginable to the CD’s inventors. The separation of the digital-to-analog converter from the CD player in the late 1980s opened the door to a relentless pursuit of innovations and improvements in every sub-system of the process of converting a stream of ones and zeros into music. From the input receiver, to digital filtering, to clocking, to power supplies, to grounding schemes, to the DAC chips, to the analog output stage, every aspect of the conversion process has been continuously re-invented for better sound quality.
DACs have not only become better-sounding, but are now also laden with a wide range of spectacular capabilities. Once a simple box with a couple of SPDIF digital inputs and a fixed-level analog output, today’s DAC may offer analog inputs with source switching (obviating the need for a linestage in your system), selectable digital filters with various upsampling options, DSD decoding, MQA compatibility, network connectivity, the ability to be controlled by a phone or tablet, integral streaming-service support, Internet Radio, and seamless integration with the music-management software Roon.
The culmination of the last three decades of hard-won technical breakthroughs and ever-expanding features must surely be the new SDV 3100 HV DAC and PDT 3100 HV CD/SACD transport from Germany’s Theory + Application elektrokustik (T+A). These two products are perhaps the most sophisticated digital products extant in both design and functionality. It is no coincidence that they were created by a company that has been at the forefront of digital audio advancements for nearly 30 years. Even though I’ve been closely following DAC technology since early 1989, I was surprised to learn that T+A programmed its own digital filters on general-purpose DSP chips way back in 1989, with the first commercial implementation in 1992. I had thought that only Wadia Digital, Theta, and, a little later, Krell, wrote their own filter code in that era.
Features and Capabilities
The SDV 3100 HV is packed with advanced features and capabilities. It is a network streaming DAC with integral support for Tidal, Qobuz, and Deezer. Although one of its inputs is labeled Roon Ready, the SDV is currently undergoing Roon certification. The SDV offers FM, FM-HD, a DAB (Digital Audio Broadcasting) tuner, and aptX Bluetooth for wireless streaming. It will decode PCM up to 768kHz (on the USB or network input; 192kHz on SPDIF) and DSD up to DSD1024 (16 times the base DSD frequency that is used in the SACD format). The SDV doesn’t decode MQA (more on this later). In practice, all this adds up to a one-box component that can access just about any digital media or format. T+A’s app allows you to control all this functionality from your phone or tablet.
In my system, I connected the SDV to my network and streamed music from Tidal and Qobuz via Roon. I also played music from a Fidata 2TB solid-state NAS through the network, and drove the SDV’s digital inputs with the output of an Aurender W20 music server. The T+A app allowed me to select sources, change the SDV’s digital filter, and adjust the balance and other functions that are normally handled by a traditional remote control. If app control isn’t your thing, T+A includes with the SDV a large and comprehensive remote.
In addition to this staggering array of options, the SDV also offers a full complement of traditional digital inputs, including AES/EBU, six SPDIF (two RCA, two BNC, two TosLink optical), two HDMI, and two USB inputs. One of these USB inputs is “device mode” for connecting the USB output from a computer or music server; the second is “master mode” that connects to a mass-storage device such as a NAS or USB stick. When playing files stored on a NAS through master-mode USB input, the SDV is said to be a “streaming client.” Driving the SDV from a Windows PC requires a driver installation on the PC. The SDV is UPnP (Universal Plug ’n’ Play) and DLNA (Digital Living Network Alliance) compliant. This means that the SDV is compatible with the protocols that allow all UPnP devices on the network to discover each other and exchange data.
The SDV has another digital connection, T+A’s proprietary IPA-Link that is used exclusively to connect the SDV to the companion PDT 3100 HV CD/SACD transport. This umbilical transmits PCM and DSD data directly from the transport to the DAC without the compromise of conventional digital interfaces.
Rounding out the connections are an FM antenna input, wireless LAN antenna input, H-Link that synchronizes the product’s operation with other T+A components, and two HDMI inputs with ARC (Audio Return Channel) if you’re using the SDV in a system with a television.
The SDV’s myriad input names are displayed on a large front-panel screen. The large volume-control knob doubles as a source selector; just push the knob and then scroll through the inputs. The second large front-panel knob allows you to navigate the display’s many functions, from setting up the network connection to directly choosing music stored on a NAS. The display also shows the name of the track being played, either from a streaming digital source (provided that source includes metadata) or from the PDT 3100 HV transport. Below the display are a row of touch-sensitive buttons that turn the power on and off, access more advanced functions (such as network setup), and track playback when in streaming-client mode. Finally, the front panel offers headphone outputs on balanced and unbalanced jacks.
Why, I remember the day when I could completely describe a DAC’s inputs, functions, features, and controls with the sentence: “The DAC offers SPDIF and AES/EBU inputs, selectable by a front-panel toggle switch.” We’re living in a different world.