T+A SDX 3100 HV Reference Streaming DAC Preamp – streaming, D/A conversion and preamplifier at reference level

With the T+A SDX 3100 HV Reference Streaming DAC Preamp, T+A elektroakustik GmbH & Co. KG is introducing a new source and control centre for the upper reaches of the T+A HV Series. Developed in Herford as the successor to the T+A SDV 3100 HV, it brings network streaming, digital-to-analogue conversion, analogue source management, preamplification and headphone drive into a substantial aluminium chassis. The headline technologies include the third generation of the T+A Audiophile Streaming Architecture, dedicated conversion paths for PCM and DSD, and a completely redesigned analogue preamplifier. Fully analogue tone adjustment and optional phono modules broaden its remit still further, allowing the T+A SDX 3100 HV to sit at the centre of systems ranging from resolutely digital installations to elaborate mixed-source reference set-ups.

Key Facts T+A SDX 3100 HV Reference Streaming DAC Preamp

• Reference Streaming DAC Preamp from the T+A HV Series
• Successor to the T+A SDV 3100 HV
• Third-generation Audiophile Streaming Architecture – ASA G3
• T+A Path Separation Technology with independent PCM and DSD signal paths
• PCM playback via USB at up to 32 Bit and 768 kHz, with native DSD processing via USB up to DSD 1024
• Quadruple PCM Converter using four 32 Bit Burr-Brown converters
• T+A True 1-Bit DSD Converter without conversion to PCM
• De-Jitter Masterclock with two femto crystal oscillators
• Fully balanced preamplifier section in double-mono architecture
• Fully analogue tone control with independent adjustment for each channel
• Class A headphone amplifier with 6,3 mm jack and 4,4 mm Pentaconn connections
• Optional phono module for MM or MC cartridges
• Apple AirPlay 2, Spotify Connect, TIDAL Connect and Qobuz Connect, plus Amazon Music HD, Deezer and HIGHRESAUDIO; Roon support was still undergoing certification at market launch
• Bluetooth 5.4 including aptX HD
• HDMI inputs and HDMI output with ARC
• Substantial 17 × 46 × 46 cm chassis weighing 26 kg, available in silver and titanium
• Price: € 32.500,-, available immediately

A New Reference Hub for the T+A HV Series

It would be misleading to regard the T+A SDX 3100 HV simply as a streaming DAC. T+A elektroakustik GmbH & Co. KG sees it as the command centre of a complete High-end system: a component capable of managing digital and analogue sources, controlling system volume and driving a separate power amplifier directly.

The underlying idea continues the work begun by the T+A SDV 3100 HV, but the new model reaches considerably further, particularly in its treatment of analogue signals. The conversion architecture has been revised, the streaming platform replaced by a new generation, and the preamplifier section developed afresh rather than lightly modified. T+A has also expanded the analogue connectivity and introduced a sophisticated tone-control system that deliberately avoids digital signal processing.

Its modular construction is intended to protect the component against premature obsolescence. An optional MM or MC phono module can be fitted, allowing the T+A SDX 3100 HV to become the control centre of a serious vinyl system without the need for an additional external phono stage.

This breadth is central to the product’s identity. It is not a streamer with a volume control appended to it, nor a conventional preamplifier with network functionality added as an afterthought. T+A has treated the digital source platform, conversion stages and analogue control circuitry as separate disciplines that happen to occupy the same chassis.

T+A Audiophile Streaming Architecture G3

Network playback is built around the third generation of T+A’s proprietary Audiophile Streaming Architecture, abbreviated to ASA G3. The platform provides access to subscription services, local network libraries, internet radio and playback from mobile devices.

Direct service support covers Amazon Music HD, TIDAL, Qobuz, Deezer and HIGHRESAUDIO. Spotify Connect, TIDAL Connect and Qobuz Connect are included alongside Apple AirPlay 2, while integration with Audirvāna provides another route for users running computer-based music libraries. Roon integration was still in the certification process when the product entered the market.

Music stored locally can be accessed through Ethernet, WiFi, attached USB storage or network shares. The streaming client handles Linear PCM at up to 24 Bit and 384 kHz as well as DSD64, DSD128 and DSD256. The converter section itself accepts still higher data rates through its USB device input, reaching Linear PCM at up to 32 Bit and 768 kHz and DSD at up to DSD 1024.

Control is provided by the T+A MusicNavigator G3 app for Apple iOS and Google Android. Those who prefer a physical interface can use the controls on the front panel or the supplied T+A F 3100 remote handset, which is constructed from metal rather than lightweight moulded plastic.

That distinction matters in a component intended to serve as the daily interface to an entire system. Streaming products often place considerable emphasis on software while treating physical operation as secondary. The T+A SDX 3100 HV retains the tactile, direct control expected of a traditional reference preamplifier while offering the broader access of a contemporary network source.

Separate Conversion Paths for PCM and DSD

One of the defining technical decisions in the T+A SDX 3100 HV is the strict separation of PCM and DSD processing. Rather than passing both formats through a common converter architecture, or converting DSD into PCM before the final conversion stage, T+A assigns each data format to a dedicated signal path designed around its particular requirements.

DSD data is sent to the T+A True 1-Bit DSD Converter. This circuit processes the original 1 Bit stream natively and accepts data rates through USB up to DSD 1024, equivalent to 49,2 MHz. The signal is not converted into PCM beforehand.

Linear PCM material is handled by a symmetrically configured Quadruple PCM Converter. The circuit uses four 32 Bit Texas Instruments Burr-Brown digital-to-analogue converters, providing a total of eight conversion channels. Their particular configuration is intended to average out individual converter nonlinearities while reducing the already low noise floor by a further 6 dB.

Four oversampling algorithms are available for PCM: short FIR, long FIR, Bezier/IIR and Bezier. These are not merely cosmetic filter labels but alternative approaches to the way reconstructed waveforms are calculated and time-domain behaviour is managed.

Downstream of the digital conversion stage, the analogue filter takes the form of a third-order phase-linear Bessel design. Its cut-off frequency can be switched between 60 and 120 kHz, allowing the output filtering to be matched to the chosen conversion mode and system requirements.

T+A’s approach is deliberately format-specific. PCM and DSD may both represent digital audio, but their coding principles and conversion requirements are fundamentally different. The T+A SDX 3100 HV therefore avoids forcing them through a single compromise architecture.

De-Jitter Masterclock with Two Femto Oscillators

The independent converter paths are supported by a multi-stage T+A De-Jitter Masterclock. Its purpose is to identify timing deviations in incoming digital signals and prevent those deviations from influencing the actual conversion process.

The clock embedded in the incoming signal is analysed first. Should it fail to meet the prescribed requirements for frequency accuracy and stability, the signal passes through an additional phase-locked loop stage. According to T+A elektroakustik GmbH & Co. KG, this second stage reduces the remaining jitter by a further factor of four.

Clock generation is then taken over by two separately optimised femto crystal oscillators. One is dedicated to frequencies derived from the 44,1 kHz family, while the other handles multiples of 48 kHz.

This arrangement allows the converter circuitry to operate largely independently of the original source clock. Rather than attempting to polish an inherently unstable timing reference indefinitely, the T+A SDX 3100 HV analyses, conditions and ultimately replaces it with a locally generated clock appropriate to the relevant sampling-frequency family.

The use of two oscillators also avoids deriving one frequency group from an oscillator fundamentally intended for the other. It is an expensive and technically elaborate solution, but entirely consistent with a component whose converter section is expected to handle everything from conventional digital sources to DSD 1024.

A Newly Developed Double-Mono Preamplifier

T+A developed the preamplifier section of the T+A SDX 3100 HV from the ground up. It employs the company’s HV circuit technology, uses discrete components and is configured as a fully balanced double-mono design for the two audio channels.

The analogue circuits are galvanically isolated from the digital section. This separation is intended to reduce crosstalk and unwanted interaction between the individual functional areas while maintaining a wide dynamic reserve.

T+A specifies channel separation at 110 dB, with both total harmonic distortion and intermodulation distortion claimed to remain below 0,001 per cent. Such figures are not achieved by treating the preamplifier as a simple output buffer for the DAC. They require a genuinely independent analogue gain and control stage.

Volume adjustment is handled by a relay-controlled precision module. Gas-tight sealed relays switch the individual attenuation steps, and the deviation between the two channels is said to remain below 0,05 dB even at an attenuation of -60 dB.

That last figure is especially relevant at low listening levels. Conventional potentiometers and less elaborate electronic attenuators can exhibit greater imbalance as the volume is reduced, causing voices and instruments to shift subtly away from their intended positions. The relay architecture is designed to preserve the stereo image even when the system is playing quietly.

The preamplifier is therefore not a concession to convenience. It is intended to perform as the analogue control stage of a reference installation, including systems in which the T+A SDX 3100 HV is partnered directly with a high-output stereo or mono power amplifier.

Analogue Tone Control Rather Than DSP

A less predictable feature of the T+A SDX 3100 HV is its entirely analogue tone-control system. Adjustments do not alter the digital data stream, nor do analogue sources need to undergo an additional analogue-to-digital and digital-to-analogue conversion before correction can be applied.

Bass and treble can be raised or reduced, but the user is not restricted to fixed turnover points. The operating frequencies for each range can also be selected, making the controls considerably more adaptable than the elementary tone circuits found on conventional integrated amplifiers.

Where necessary, the left and right channels can be adjusted independently. This permits measured, targeted correction for asymmetric rooms, unequal boundary conditions, non-symmetrical loudspeaker placement or recordings whose tonal balance is less than ideal.

Used carelessly, any tone control can become a blunt instrument. That is not the intention here. T+A has designed the system as a corrective facility for specific circumstances rather than a permanent overlay on every recording.

When set to neutral, the entire tone-control section can be removed from the signal path. Purist operation and practical room adjustment are therefore not mutually exclusive: the user can bypass the circuitry for an uncompromised direct path, then engage it when a particular room or recording genuinely benefits from intervention.

Optional Phono Modules for MM or MC

T+A elektroakustik GmbH & Co. KG offers two optional phono modules for the T+A SDX 3100 HV. One is intended for moving-magnet cartridges, the other for moving-coil designs.

Compared with the previous solution, the phono circuits now take the form of easily installed plug-in modules. Installation and adjustment are carried out at the rear of the T+A SDX 3100 HV, where the relevant parameters can be configured for the cartridge in use without opening the entire component.

Once installed, the module benefits from the power supply and the mechanically and electromagnetically screened construction of the HV platform. No separate phono power supply is needed, and there is no additional interconnect between an external phono stage and the preamplifier.

This is a more significant advantage than the simple saving of shelf space. Low-level cartridge signals are particularly susceptible to noise, hum and electromagnetic interference. Housing the module within the shielded architecture of the T+A SDX 3100 HV gives T+A direct control over power, grounding and signal routing.

The choice between dedicated MM and MC versions also avoids building a universal circuit around unnecessarily broad operating compromises. Owners can specify the module appropriate to their cartridge type and integrate vinyl replay without changing the fundamental system architecture.

Class A Headphone Amplifier with 6,3 mm Jack and 4,4 mm Pentaconn

Headphone playback is handled by a dedicated analogue amplifier rather than by an auxiliary output stage derived from the main preamplifier circuit. The discrete headphone amplifier operates in pure Class A and, according to T+A elektroakustik GmbH & Co. KG, can deliver currents of up to 200 mA.

The front panel provides both a conventional 6,3 mm stereo jack and a balanced 4,4 mm Pentaconn connection. Output impedance is specified at 6 Ohm.

The available current is intended to support low-impedance headphones that present a demanding electrical load, while the output voltage is designed to accommodate more difficult high-impedance models. This gives the headphone section a broader working range than the token outputs still found on some otherwise ambitious source components.

The inclusion of both connection standards is equally sensible. The 6,3 mm socket preserves compatibility with established home headphones, while the 4,4 mm Pentaconn connection addresses a growing range of balanced headphone cables without resorting to an oversized four-pin XLR socket on the front panel.

As with the main preamplifier, the headphone stage has been treated as a genuine analogue component in its own right. It is not simply there to complete a feature list.

Digital Connectivity Including HDMI ARC

The T+A SDX 3100 HV is not restricted to network streaming. External digital sources can be connected through one AES/EBU input, two coaxial RCA inputs, two high-quality BNC inputs and two optical TOSLink interfaces.

Two HDMI inputs are joined by an HDMI output with Audio Return Channel, commonly abbreviated to ARC. This makes it possible to route television sound directly through a high-quality stereo system without adding a separate AV processor or relying on an optical connection.

Two USB device ports provide connections for computers, while a further two USB host interfaces accept external storage media. The distinction allows the T+A SDX 3100 HV to operate both as an asynchronous USB DAC for a computer and as a standalone player for locally attached music libraries.

Network access is provided through Gigabit Ethernet or WiFi conforming to IEEE 802.11a/b/g/n/ac/ax with 2 × 2 MIMO. Bluetooth 5.4 supports SBC, AAC, aptX and aptX HD.

Radio reception has not been omitted. The T+A SDX 3100 HV includes DAB, DAB+ and FM, supplemented by the airable TuneIn internet-radio service.

Taken together, the connectivity reflects the product’s intended role as a system controller rather than a narrowly defined network player. A television, computer, disc transport, server, USB drive, mobile source and conventional radio service can all be incorporated without displacing the unit from its central position.

Substantial Aluminium Chassis with Physically Separated Sections

The chassis of the T+A SDX 3100 HV is made from non-magnetic aluminium. Internally, precision-machined aluminium plates measuring between 10 and 15 mm in thickness separate the individual functional sections.

This physical division is intended to reduce electromagnetic interference between the streaming platform, digital electronics, converters, preamplifier and power supply. It also prevents the internal architecture from becoming a densely packed collection of mutually exposed circuit boards.

At 26 kg, the enclosure provides a mechanically stable foundation for the sensitive analogue circuitry. The mass is not merely decorative, nor is it solely a consequence of an imposing outer case. It reflects the extensive internal partitioning, power-supply provision and structural isolation employed throughout the component.

The T+A SDX 3100 HV measures 17 cm in height and 46 cm in both width and depth. It is available in the silver and titanium finishes traditionally associated with the T+A HV Series.

Its proportions and weight make its intentions perfectly clear. This is not a compact lifestyle streamer designed to disappear into furniture. It is a full-scale reference component engineered to match the construction, appearance and system authority of the other models in the T+A HV Series.

The Most Important Benefits at a Glance

• A complete reference control centre: Streaming, digital conversion, analogue source management, preamplification and headphone drive are handled by one component, reducing the need for a stack of separate control units.
• Conversion tailored to each format: PCM and DSD follow independent paths, allowing each data type to be processed by architecture developed specifically for its underlying format.
• Native DSD without an intermediate PCM stage: The T+A True 1-Bit DSD Converter preserves the original 1 Bit signal structure and accepts data through USB at up to DSD 1024.
• Broad access to streamed and locally stored music: ASA G3 combines major subscription platforms, Connect services, Apple AirPlay 2, network libraries and attached USB storage within one operating environment.
• Stable stereo imaging at low volume: Relay-switched attenuation maintains exceptionally close channel tracking even when listening at heavily reduced levels.
• Room correction without digitising analogue sources: Bass, treble and their operating frequencies can be adjusted entirely in the analogue domain, including separate settings for the left and right channels.
• Straightforward integration of serious vinyl replay: Optional MM and MC modules allow a turntable to connect directly to the T+A SDX 3100 HV without a separate phono stage or power supply.
• A headphone stage designed for demanding loads: The discrete Class A amplifier provides both 6,3 mm and 4,4 mm connections and is specified to deliver up to 200 mA.
• Television sound through the main stereo system: HDMI ARC allows a compatible television to use the T+A system without an additional audio interface.
• A platform designed for long-term system development: Its extensive digital and analogue connectivity allows owners to add power amplifiers, sources, storage and phono replay without replacing the central control component.

Price and Availability

The T+A SDX 3100 HV Reference Streaming DAC Preamp is available immediately through authorised specialist retailers. The recommended retail price is € 32.500,- in both silver and titanium.

The optional phono module is offered in separate versions for MM and MC cartridges, each priced at € 1.390,-.

Conclusion

The T+A SDX 3100 HV is far more than a cautiously updated streaming DAC. T+A elektroakustik GmbH & Co. KG has brought together duties that are often spread across several High-end components, yet it has done so without reducing the analogue preamplifier to a supporting role or placing every signal under digital control.

Its combination of third-generation ASA G3 streaming, format-specific conversion, precision relay attenuation, adjustable analogue tone correction and optional phono capability makes it unusually complete. More importantly, those features belong to a coherent system architecture rather than an indiscriminate catalogue of facilities.

The separate PCM and DSD paths reveal the seriousness of the digital engineering, while the double-mono preamplifier, galvanic separation and analogue correction facilities demonstrate that the analogue side has received equal attention. HDMI ARC, Bluetooth and app control broaden its everyday usefulness, but they do not define the product.

At € 32.500,-, the T+A SDX 3100 HV occupies the highest tier of the market and makes no attempt to disguise the fact. In return, it is conceived as a long-term reference control centre capable of forming a complete system with little more than a suitable stereo power amplifier and loudspeakers. For owners building around the T+A HV Series, it may be the most consequential component in the range: the point at which every source enters, every signal is governed and the character of the entire system is ultimately determined.

Technical Specifications