Burson Audio Soloist 3X Grand Tourer

Headphone amplifiers are part of everyday life without us being directly aware of it. For example, they can be found in everyday devices such as smartphones (to the list of the best headphone amplifiers). In parallel, a trend has developed towards high-quality headphones that require an adequate amplifier for proper control and full development of sound. Here, we look at what Burson Audio can contribute to this.

Company History

Over 20 years ago, Burson Audio was founded by a team of sound engineers. Based in Melbourne, the company develops high-quality audio equipment and audio design components for hi-fi enthusiasts and production partners. A fundamental principle in product development is the manufacture of proprietary circuits and the selection of high-quality electronic components to achieve high-end results. The portfolio focuses on headphone amplifiers and converters.

Design

The model we are testing here, the Burson Audio Soloist 3X Grand Tourer, arrives in sturdy packaging. Included are the external power supply, remote control and six JRC 5532D operational amplifiers for sonic fine-tuning. The unit’s operation and connections are self-explanatory, so there was no need to look at the manual.

The solidly designed front panel made of CNC-milled, brushed aluminium is eye-catching. A solid aluminium plate was also used for the rear panel so that all connections are solidly screwed to the rear panel instead of being attached to the circuit board. Everything fits tightly and promises longevity.

The inner workings are housed in a silver 6mm thick aluminium case, which also serves to cool the high-quality components with metal ribs all around. In the centre of the top side, a rounded recess serves to discharge air from the active fan that is integrated underneath. The extremely quietly rotating fan is made by Noctua and has a diameter of 120mm. In combination with the low-resonance cooling housing, this results in a noise level of less than 25dB during operation.

The clean design of the front features a logical arrangement of the controls. On the left are the headphone connections, in the middle is the display with selection buttons underneath and on the right is the solid volume control, milled from a single piece, which offers a good grip and is easy to use.

The medium-sized cabinet can be easily integrated into an existing hi-fi system or studio environment. The unit’s mighty 5kg provides stability when changing headphones. An additionally available Cool-Stand allows for a 90-degree rotated positioning. All in all, the unit leaves a superior impression with its minimalist look and aluminium housing.

Connections and operation

There is a four-pin XLR and a 6.35mm jack socket for connecting headphones. In addition, there is a four-pin 3.5mm connector for gaming headsets, which allows the headset microphone to be used. Of the devices I’ve tested, this is the first of this kind that also integrates gaming headsets. Above that is the on/standby switch.

Below the display are the selection buttons for the input and output sections, the device settings and a display rotation of 90 degrees when using the cool stand.

The display provides visual feedback on the selected functions of the buttons and shows the status of the inputs and outputs and the volume control. The latter functions digitally in 99 increments.

The rear panel offers two pairs each of balanced XLR and unbalanced RCA inputs. Since the unit can also serve as a preamplifier, balanced and unbalanced outputs are also offered, including a separate subwoofer output. The equipment is completed by 12-volt trigger inputs and outputs and an additional microphone input. Finally, the connection for the external power supply unit is also located here.

Preamplifier

The Burson Audio Soloist 3X Grand Tourer is not only a headphone amplifier but also a preamplifier. It can be configured as a headphone amplifier, as a preamplifier or as a combination of headphone amplifier and active subwoofer. As a preamplifier, it can optionally feed a power amplifier with passive loudspeakers or directly connected active monitors. With four analogue input pairs, there are sufficient connection options for the desired sound sources.

Technology

The Burson Audio Soloist 3X Grand Tourer is based on an all-analogue Class A system with an output power of 10 watts per balanced channel. Even the unbalanced channels still deliver half the power. This means that the unit offers more than twice as much power as the competition, which means that even low-power headphones can be driven. The dual-mono design is fully balanced, ensuring low-noise transmission with low crosstalk between the channels.

In the basic setting, the Soloist offers three gain stages. For the volume control, Burson comes up with a special feature: A typical stereo volume control creates interference between the channels. In order to reduce this, special components from Muses are used; these are usually found in higher-priced devices from PassLabs and AVM. These chips are combined with discrete V6-Vivid operational amplifiers, which in turn increase channel separation while improving the precision of the volume control. The result is a channel separation of 120 dB. If you want to get into modification yourself, Burson even offers special operational amplifiers that can be used to further tune the headphone amplifier and vary its sound.

Finally, the Soloist 3X Grand Tourer also offers a crossfeed function that mixes part of the right channel to the left side and vice versa. The aim is to imitate the behaviour of loudspeakers but also natural listening on headphones. Perfect channel separation is thus reduced and a centre is added to the stereo field.

Sound

The wireless MTX monitor with integrated headphone amplifier served as the playback device for the possibility of direct comparisons. Other playback devices used were a Cambridge Audio CXN V2, a CD player (NAD 512), a smartphone (Samsung Galaxy S7) and an iBasso DX240 Reference DAP. Headphones were represented by models from Stax, Sendy Audio Peacock, Hifiman Edition XS, Focal Spirit Professional, Sony MDR-V600 (45 ohms), iBasso SR2 and the Sennheiser HD 25 MKII were covered.

The power-hungry Hifiman Edition XS (18 ohms) blossomed into unimagined soundscapes in combination with the Soloist 3X. Finally, an amplifier that can supply this magnetostatic with the right amount of power and still have plenty of room for improvement. This also enables a finer dynamic gradation and thus a more accurate listening level.

The Burson Audio Soloist 3X Grand Tourer delivers powerful low frequencies, which were audible on all my headphone models or could be sensed depending on the model. With the Sendy Audio Peacock, for example, the bass was profoundly deep but was nevertheless tonally well-defined. With the cheaper headphone models, I missed such precision and clear resolution. Here, the bass frequencies expressed themselves more through pressure than through tonality, but still with beautiful sound reproduction.

The midrange sounded effortless and differentiated the instruments in distinct contours. The Soloist 3X provided an extremely precise sonic insight into this dense frequency range, which holds a lot of musical information. Vocal passages were fully articulated and reproduced with an ease that was second to none. At the same time, microtonal fluctuations were mercilessly revealed. And this could even be experienced with the cheaper headphone models.

The high-frequency range benefited from the extended frequency range up to 48 kHz, where the treble sounded open upwards and exuded an acoustic brilliance. This range also excelled with an articulated richness of information and detail.

The virtual soundstage sounded wide open with enormous spatial depth. The entire width of the stage was covered without excessively stretching the image. As if divided into layers, the sound sources lined up one after the other in detail and revealed a precise breakdown of their position – depth staggering par excellence. Thanks to the excellent transient response, impulsive music flowed out of the headphones in a relaxed manner. Instruments with high transients, such as a snare, were reproduced with bravura.

The Soloist does not get rattled and always delivered crystal-clear transparency. In terms of timbre, it played rather neutrally. Another quality of the unit we tested was its explicitly low noise level below the listening area. As a result, the finest sound elements became audible in the lowest dynamic range, which benefited dynamic-rich genres such as classical music, jazz, folk and ambient music in particular.

In addition to operating purely as a headphone amplifier, a subwoofer can be operated in parallel to headphones in the “Head+Sub” configuration. This is an unusual but sensible configuration to support the physical sensation when listening. It can contribute to a more intense bass experience that may well be perceived as speaker-like, even avoiding the acoustic pitfalls of the room. In fact, the added value in sound was clearly noticeable and audible, and I experienced an enhanced experience of physicality despite the good bass reproduction via headphones.

All the positive qualities mentioned for listening to music can be transferred to a studio environment without restriction. The Burson Audio Soloist 3X Grand Tourer is thus also ideally suited for the neutral assessment of a mix.