Burson Soloist 3X Performance

The one thing nobody argues about. Burson rates 8 W into 16 ohms and 4 W into 32 ohms from the balanced output (half that single-ended), and the measurements came in above the spec at high impedance. Reviewers drove a Susvara, HE-6, Abyss AB-1266 and 600-ohm Beyerdynamics with headroom to spare, and one compared it favourably with amps rated at twice the wattage because it never shut down on sustained bass. The bench's only caveat is that distortion rises early in the power sweep, not that power runs out.

“This may be the most powerful headphone amplifier I have tested”

amirm · Audio Science Review

“As of right now, Soloist 3X felt like the most powerful headphone amplifier that passed through these hands.”

Sandu Vitalie · soundnews

“almost endless power is available through the balanced connector”

Sword of Damocles · Kuulokenurkka

“Given the very high amount of power and an output impedance pretty close to zero, Soloist 3XP will drive any dynamic or planar headphone connected, even the very hard to drive HE-5 and HE-6 from Hifiman.”

raoultrifan · Head-Fi

Sources split, and the split tracks the gain setting and who held the unit. Reviewers with loan units mostly report a near-silent background on low gain, even with very sensitive IEMs. The benches and many owners report the opposite on medium and high gain: an audible hiss with sensitive headphones, low-level performance ASR placed in the poor category of all the amps it had tested, and in some units hiss that comes and goes at particular volume steps. One reviewer found the stock 24 V brick audibly whined; Burson's optional Super Charger supply fixed that and cut out-of-band noise on the bench, but not the in-band floor. Channel balance, by contrast, is perfect at every volume thanks to the MUSES chip.

Sources split three ways, in the classic electronics argument. Two independent benches found distortion far above competing amps — worst at the default medium gain, better on high gain and best with the volume chip bypassed — with a falling harmonic series of the kind associated with tube amps. Listeners then divide: one group hears exactly that, a warm, organic, tube-like sound (one critic called it muddy); a larger group hears a clean, transparent amp with only a touch of smoothness, and one owner even found it clinical next to a Violectric. An analysis on the bench thread argues the distortion is mostly second-order and below audibility at normal listening levels — which is also what the bench's own listening test found. Op-amp choice and the power supply move the sound, so units genuinely differ.

Unusually complete for a headphone amp. Balanced XLR and RCA inputs, a balanced XLR preamp output (switched from the menu, so speakers and headphones never play together), three gain settings, an aluminium remote, a 'Headphone Power Amp' mode that bypasses the volume chip, and a 3.5 mm headset jack that routes a microphone out the back for gaming or calls. The missing pieces reviewers name are an unbalanced line output, a 4.4 mm jack, and the fact that the balanced preamp out cannot simply be adapted to RCA without Burson's own adaptors.

“Soloist 3X has also a super-cool feature called Headphone Power Amp Mode.”

Sandu Vitalie · soundnews

“I have not seen a similar solution in any other headphone amplifier over 1000 euros, but it is probably a nice extra feature for gamers.”

Sword of Damocles · Kuulokenurkka

“No unbalanced line-level outputs.”

raoultrifan · Head-Fi

The most consistent list of complaints in the record. The digital volume knob has no acceleration, so going from 99 to 0 takes many turns; some steps misbehave (volume drops between 19 and 20 and between 35 and 36, and jumps several decibels between 51 and 52 — reportedly fixed in later production, and Burson sent at least one owner a replacement chip); gain is buried in a menu whose order runs backwards; the rear XLR jacks are not marked left and right; and the whole case runs hot. A few reviewers found the simple menu and remote perfectly usable, and heat reports range from warm to too hot to touch.

“We are talking many turns to go from 99 to zero.”

amirm · Audio Science Review

“The jump from 51 to 52, on the other hand, increases the volume by several decibels instead of 0.5 decibels.”

Sword of Damocles · Kuulokenurkka

“First of all, on its back panel the XLR inputs and outputs are not labeled at all”

Sandu Vitalie · soundnews

“Burson runs super hot; it's really hot to the touch.”

phalanx2357 · r/headphones

Sources split between the box and what is inside it. The finned, CNC-machined aluminium case, Neutrik jacks and densely packed boards draw consistent praise. Against that, the bench thread and owner forums carry a run of protection and QC reports: high DC offset for the first 10–15 minutes after power-on (measured by two benches and an owner-reviewer), op-amp sockets that fit some op-amps badly, no output protection against a failing op-amp, op-amps that died in use, a unit that died after a month, and two owners whose headphones were damaged by a loud pop — one traced to a faulty op-amp, with Burson replacing parts. Burson's support advice was to plug headphones in only once the amp is on.

Sources split almost exactly in half. Reviewers who prize its power and sound call it fair or even a bargain at about $1,150 — cheaper than the boutique amps it was compared with, and one of very few under $2,000 that comfortably drives a Susvara. The bench and several owners counter that far better-measuring amps cost much less, that one reviewer had to add Burson's ~€280 power supply to make it sound right, and that European pricing was steep. Now discontinued, it trades used at around $900–1,000, which shifts the sums.