Australian manufacturer Burson’s Conductor Virtuoso V2+ comes with a DAC, a headphone amp and doubles the output of the original version to 8W into 16 Ohms. Janine Elliot dons her cans and takes this £1590 unit for a test drive. 

Burson and I have two things in common. The first one is that we both don’t like op-amps. Op-amps might be great for pc’s and equipment short of space but there are many drawbacks having individual “components” printed on a miniscule composite the size of a grain of rice using a process of photolithography. The technology might be breath-taking almost following the Moore’s law in that the number of components in the space seems to get more and more every year, but this does mean that because they get smaller and closer together there is more likelihood of EMI noise and less tolerance to heat, let alone reduced specification. An op-amp could easily have as many as 50 inferior components squeezed onto it. Burson Audio do manufacture 8-pin op-amps such as the V6 Classic and Vivid, and whilst they still fit into conventional 8-pin DIP sockets what makes them different is that they contain discrete full-size components meaning that the ‘box’ they are in is significantly bigger in size.

Burson also share a dislike for Class-D amplification, though my preference for Class A is diminishing as the recent Class of 2017 and 18 have graduated. Burson is quite emphatic about how they feel;

“..class-D and class-T chips were created for the car audio industry and subsequently for mobile phones where power efficiency, size and budget are the driving design parameters so audio performance is secondary if that”.

They believe Class-D circuitry is overtly complex and reduces the purity of the music. I have listened to both Class-D and A headphone amps, and my favourite is class A and presently use a Class-A/b portable headphone amp for my serious portable listening. That said I have recently reviewed some highly recommended Class-D products from around the globe.

Today’s headphone amplifiers are becoming available more and more with the option for a built in DAC as we become more and more digitally minded. Even the latest top of the range Stax Energiser, the SRM-8000, comes with a blanked-off plate on the rear suggesting, perhaps, that a DAC card might one day find its way inside that unit.  Similarly, the Conductor V2+ is more than just a headphone amp. This is a three-in-one headphone amp, DAC and preamp. It comes as a refined replacement to the original V1 headphone pre-amplifier, and in the “+” model denoting the addition of a DAC.  This is the third generation of Conductor, maintaining the looks of the original but with improved electronics. It keeps with Burson’s philosophy of being fully discrete and uses their excellent V5 SS op-amp.  As Alex from Burson proudly told me;

“The entire Conductor V2+ is pure Class A which means it is running at full capacity all the time. To us, using fully discrete, pure Class-A circuitry is the ideal design for audio amplification.”

Powered by two large 70W high density (lots of windings) transformers, twice the size of the original model, tuned to operate in pure Class A using Field Effect Transistors, the V2 doubles the output of the original model attaining no less than 8W in 16 ohm per channel to more than satisfy even the most inefficient planar cans.  Do remember that for thirsty 300 ohm Sennheiser HD650’s that does reduce it all to 500mW, though that is still more than adequate.  All this power does mean that it creates a lot of heat, and therefore the cabinet is carefully sculptured on 6mm thick aluminium around its body so that heat is dissipated uniformly around the whole casing. The case is effectively a giant heat sink.

Of course, no ground-breaking DAC for 2018 could appear without the iconic ESS Sabre DAC, in this case, the ESS9018S chip, though it is important to stress that the whole of any DAC is greater than the sum of its individual parts. The housekeeping around the DAC is equally as important. I have reviewed some lesser DACs that actually sound mightily impressive due to how the whole decoding, filtering and amplification stages work in tandem. This should also include the power supply connected to it.  As Alex from Burson informed me;

“The Digital section of the Conductor V2+ is powered by its own separate transformer and fully discrete power supply network”. 

The V2+ 9018 DAC board – one of several boards all beautifully laid out inside the unit – pushes the SABRE32 to its limits and employs 20 carefully-selected and matched components. The V2+ also employs the PGA2310 flagship 100 step volume control chip offered by Texas Instruments. Allowing a fine control of 0.5dB steps and dynamic range of 120dB and 0.0004% THD, this is a welcome addition to the circuitry. Whilst the trained human ear can pick up changes in volume as little as 0.5dB, this is generally only seen in the pro audio environment. Burson cleverly set the PGA2310’s op-amp output stage to unity gain so it essentially acts as a purely resistive volume control. When running digital audio the ESS Sabre DAC handles all of the volume itself, meaning it does not need to go through a separate analogue volume control. The Sabre controls the volume level for the DAC output sockets at the rear, meaning that the digital output is variable rather than fixed, as can usually be the case. Therefore the listener has the choice of how the volume levels are set;   pre-out stage uses the Texas Instruments 120dB volume control, whereas the DAC output uses the volume control through the DSP in the DAC chip. I tried both, interestingly preferring latter, but there is the choice so you can decide your own favourite.

The unit has a classy yet sparse front panel with a distinctive rotary control centre point and a button to toggle between two analogue (via RCA sockets) and three digital sources including S/PDif, Toslink and USB connectors. The volume control levels magically appear in blue dots behind the satin black or silver front panel left of the control. No need to look for pin holes on that front unit as there aren’t any. On/off toggle switch is from the rear of the unit. The unit has analogue and digital outputs meaning it can be used as a variety of applications, and as a basic preamplifier worked surprisingly competently during my review.  The unit comes with a cute aluminium remote to match the Conductor, and equally minimalist.

SUPPORT

The V2+ supports all major formats with coax/Toslink inputs up to 24bit 192kHz. Via the Win, Mac, IOS and Android compatible USB socket deploying the excellent XMOS  6-core chip it supports PCM up to 386kHz 16/24/32 bit, native DSD 64/128/256, and DSD over PCM (DoP) 64/128/256.

THE COMPANY

Burson Audio was founded by a small team of audio engineers founded in 1996, based in Melbourne, Australia, creating building blocks such as hybrid Op-Amps as well as complete audio products including a Class A power-amp mono-block, headphone amps, DACs and cables. Their philosophy is simple; have components that don’t interfere with the audio signal. Their philosophy is that if the equipment is designed well and transparent enough then the pace, rhythm, timing, dynamics, and tonality will become a natural expression of the music, and they feel this cannot be achieved with standard circuit building blocks like IC chip op-amps, IC regulators, or standard transformers. Instead, they research and develop their own discrete circuits so that every component in the signal path can perform at its peak.

MUSIC

The Queen Symphony from 1962 London born Tolga Kashif is not only a beautiful work based on Freddy Mercury’s iconic songs, but it is also extremely well recorded and performed by the Royal Philharmonic Orchestra with vocal intervention from London Voices and London Oratory Boys’ choir.  Kashif spent two years composing the Queen Symphony. He conducted the Royal Philharmonic Orchestra at its debut concert on Wednesday 6 November 2002 at the Royal Festival Hall, attended by Freddie’s mother Jer Bulsara, drummer Roger Taylor and guitarist Brian May, who all apparently found it very moving. After this, it was recorded at Abbey Road Studios later in the year. This is indeed a very moving performance, though the complexity of the melodic lines and continuing pushing of famous idioms in the busy soundstage can make for a tiring listening. It necessitates playback through equipment with wide dynamic range, speed and clarity for it not to get saturated. The Burson succeeds on all these fronts. Where Queen’s musical style relied on a certain amount of outrageousness, Tolga continues this in his orchestration, something that takes decent decoding and amplification as well as excellent headphones to pull off successfully. Sennheiser’s new HD660S headphones replace the HD650 which has been around for many years and were my reference cans for many years, the new version having lower impedance making them more useable with lower-powered amplifiers, though that is not an issue here. I love these well-priced cans because they can pick out individual phrases with engagement and detail that makes listening through headphone such fun, and the new version pulls it off to a whole new level with a fullness and detail that justifies their use in broadcasting and recording studios around the world.

Shostakovich Piano Concerto no. 1 starts with a very decisive intro before the fun begins on the piano, trumpet, and strings (Martha Argerich & Guy Touvron & Württembergisches Kammerorchester, Deutsche Grammophon).  This work is as emotional and similarly stuffed full with beautiful idioms as is the Queen, though they are not quite so tonally measured. Occasionally a simple tonal melody, such as on the muted trumpet, does allow you to breathe again and take in the scenery before heading off into another direction.  The Burson seems to understand the music and its clarity, force, and musicality to show there is indeed harmony between the individual musical components, just as there is between the components in the circuitry. This is a great performance from the orchestra, soloists, and electronics.

Neil Young Crazy Horse ‘Live Rust’ album and the track “My My, Hey Hey” is an excellently recorded live album and the Conductor handled both the mid-range voice and the acoustic guitars with panache and sensitivity. If I had to criticise the DAC at all it would be the tight and detailed top-end can sound a little too bright at times. The close mic’ing of the bass is particularly vibrant, and the reverb from the almost ‘Supertramp-esque’ solo mouth organ is allowed to decay with no sense of digital noise. My home choice Class-A headphone amplifier, whilst losing some of that detail, is slightly easier on the ears. My AT W1000 closed back cans were able to offer a more refined performance with a greater sound-stage that was hard to put down.

The Modern Jazz Quartet ‘Blues on Bach’ is a brilliantly performed album, with a very open and detailed soundstage that tests headphones, DACs, and amplifiers in one simple go, especially with the over-modulated audio in certain places. This is the same album I used in reviewing the Wyred 4 Sound DAC; a Class D headphone-amp-come-DAC. That unit similarly has an ESS Sabre DAC, though in that case the ES9028PRO chip is employed configured in quad differential mode so that with four D-A converters per channel they could achieve improved S/N ratio and output drive. The Burson, however, has chosen to use the ESS9018S chip and this time only using two channels of the 8, which with the other components on the board provides for them the best sound.

The bell “ding-dings” at the start of the track “Blues in A-Minor”, sounding like the London No9  Routemaster bus being sent on its way to the Royal Albert Hall, have weight and detail providing a surprisingly powerful bass for such a small sundry instrument. Add to that the vibraphone played by Milt Jackson traveling between the ears combined with piano and double bass and percussion, this is a memorable performance captured with finesse, power, and detail. The V2+ at level 42 out of its 99 range is more than adequate for my ears on the HD650’s. Lower harmonies from the harpsichord in “Don’t Stop this Train” combined with the vibraphone and bass melodic lines all work in harmony with control and weight and resolution. Only that the sound could be slightly too brash for the ultimate in Class-A sound, left me slightly wanting, though the shimmer and decay from cymbals was highly infectious. But at £1590 for such a well built and good looking product, this is still a worthy contender for your hi-fi rack. Even the analogue input is impressively musical and fast. This could easily be the basis for a complete hi-fi outfit, just requiring a power-amp and speakers.

Audeze’s LCD-X is a very efficient planar design which worked extremely well in the V2+. The slightly bass forward design allowed the punchy ‘Learning to Fly’ (Pink Floyd Momentary Lapse of Reason) to take off and sound authoritative with clear ride cymbal strokes, and with the vox-pop under the guitar riffs equally clear and meaningful.  The wafer-thin diaphragms and double-sided magnet array ensures a near zero distortion and uniform sound across the entire diaphragm, an ideal partner for this 3-in-one Melbourne-made kit, and this enabled a tight, and detailed sound. Unfortunately, I had to give back the headphones so continued with the closed-back AT W1000’s I know so well. These are very efficient cans, and the most comfortable ones I have, but I have to admit the best sound I heard was from the less comfortable Sennheiser and Audeze.

CONCLUSION

This is a very detailed, powerful and quick sounding unit covering all frequencies and all types of music play with musicality and sensitivity. For a three-in-one box, the V2+ is a very able and well thought-out product that also looks A+. That magical display and overall build well belies its price point, and the choice and design of components make it highly desirable. The amount of detail and power available per pound should make it highly desirable, particularly for inefficient planar headphones. Its sensitivity towards inefficient planar headphones is perhaps only slightly let down by the lack of sensitivity in some of the music I played, sounding a tad too clinical in the higher regions, but at this price, I really won’t be complaining.

AT A GLANCE

Build Quality: Excellent bullet-proof build with that magical display of volume level through the silver or black facia. Internally well-presented using top end components, including ESS Sabre DAC.

Sound Quality:  Impeccable resolution with an open yet tight and detailed presentation. Sound might be a little too bright for some.

Value For Money: At £1590 for a DAC, preamplifier and headphone amplifier this is a very competitively priced unit.

Pros: Very detailed and tight performance at all frequencies, particularly bass
Will easily drive the most inefficient Planar designs
Excellent build
Three units in one
Love the magical volume display

Cons: Top end can be a little brittle at high frequencies with some music

Price: £1590

Janine Elliot