Beyerdynamic A2 headphone amplifier review. With basic inputs, outputs, and an updated design, the A2 is an exceptional straight edge neutral sounding headphone amp that is certainly one for the audiophile.
As one of the most successful international Professional Audio come Hi-Fi brands, Beyerdynamic is a well rooted manufacturer that produces their own components and assembles almost all of their products in the engineering Mecca of Germany.
With bragging rights of a ninety year history, Beyerdynamic is certainly a well versed traditional manufacturer that represents quality and sophistication across their microphones, earphones, headphones, and headphone amplifiers. However, it is today that we shall be looking at the latest addition; the Beyerdynamic A2 headphone amplifier.
It is important to note that the Beyerdynamic A2 headphone amplifier has been created with the intention of superseding the previous generation ‘critically acclaimed A1’ amp. Subsequently production of the A1 has now ended and the A2 has become the flagship headphone amplifier, albeit with a slightly higher recommended retail price.
So far the flagship Beyerdynamic A2 headphone amplifier has been awarded with a prestigious 2014 Red Dot Design Award, but how will it fair in our tests? Let’s find out.
Unboxing, A1 Feature Comparison, Internal Inspection, and Build Quality
Arriving in the all too familiar, rather bland, forgettable Beyerdynamic packaging, the A2 is more about what it can do on the inside than the spending money on the throwaway assets. However an open of the box reveals the A2, a 1.5m IEC lead, an optional headphone stand, and mini remote infrared (to eliminate radio frequency interference) control, all encapsulated within a thick unibody foam that more than adequately protects your investment during shipping. The inclusion of an headphone stand is a great idea and does look great with your favourite headphones. To use the aluminium headphone stand all you need to do is attach it screw it in to the underside of the chassis with the supplied screws and hex key and that is all. Using the remote control is even easier, all you do is insert the battery, point, and go to have access to the volume (via a motorised potentiometer), mute, source, and standby selectors without getting out of your armchair. The remote is made from formed aluminium and closely matches the design of the A2, although the battery compartment cover is an off silver colour and is plastic. Immediately it sticks out like a sore thumb and does not do the package justice.
The Beyerdynamic A2 enclosure looks the part and is crafted from a single CNC milled aluminium block which is then sandblasted to give it a flawless matt finish. This differs from the previous generation A1 which has rubber buffers parallel along the edges, and develops further by adding another confusing dimension to the appearance. This development is in the form of a toughened glass top panel with opaque Beyerdynamic rib decals which allow for consumers to see into the inner workings of the beast; namely the FET and high output capacitor array. Unfortunately, in this area, Beyerdynamic have installed four unnecessary low output orange LED’s to create a contradicting tubesque style glow in a solid state amplifier, and there is no way to turn this feature off. Undoubtably for some this will be a novelty that they do not wish to see in a flagship high end headphone amplifier.
If we now move to the rear panel we can notice that there is your standard IEC input and a selectable voltage input switch for different regions, to the left of this we can see two separate gold plated RCA inputs with RCA input one having the option to act as a passive through, or output, to go into another input/output device. One potential issue is with the RCA post positions as the clearance is average and when we used premium RCAs (The Chord Company Signature Tuned ARAY) their plug casings came extremely close to one another. Other than this, with a headphone amplifier in this price range, it would have been a welcome addition to include an XLR input and output.
Turning our attention now back on to the faceplate we notice some familiar features including physical backlit rubber input selectors, an motorised analogue potentiometer, and a standby selector. However, the most obvious difference between the A1 and the A2 is that the A2 now has a dual ¼” output for two full size pairs of headphones, although the outputs are unbalanced. Beyerdynamic mention in the specifications that the A2 can handle headphones between 16 ohms and 600 ohms and that it is “currently the only device on the market that provides separate adjustments for the impedance and sensitivity of connected headphones as well as different levels of the audio sources.” Now, whilst we operated the A2 with two completely different headphones (Beyerdynamic T90 and Audio Technica ATH-M50, amongst many others), it felt as if both headphone outputs were tethered (in parallel) onto the same signal path instead of being separate; something that we also witnessed with the recently released Beyerdynamic A20. Although the A2 still performed well with mismatched impedance’s, we are looking at you bass and low-mid frequencies, you can only set a master volume level for both outputs and if one of the headphones was unplugged during playback the signal would jump up to a much higher level as there is no auto-sensing relay protection circuits to separate the signal paths. This can be dangerous for a number of reasons and, having tested many other headphone amps, this is a premium product that seems to not follow the trend of independent outputs.
If we forget a couple of the previously discussed shortcomings, when we look inside the Beyerdynamic A2 enclosure we are pleasantly greeted with an exceptional internal build quality. Beyerdynamic have gone to great lengths to ensure that the surface mounted signal path is as clean as possible with fully discreet ‘no integrated circuits (IC’s) components’ used in the signal path (although they are present to control the motorised potentiometer / infra red remote signal etc.) and have used the casing structure to limit radio frequency interference. In fact the input power supply comprises of a fully isolated board with double slow-blow and fast-blow fuse protection before entering a low profile 15v triodal Talema transformer with an Omron relay switch to inhibit any discharge during power on that could cause a pop that could damage headphones. Following this there is another set of fuses on the main board which, again, protects both critical components. Also other Omron relay switches are located at the source selection and mute circuits for total protection. Other premium components include Sanyo and WIMA capacitors and a motorised ALPS potentiometer. The design, sum, and implementation of these components represents outstanding build quality and attention to detail leading to an total harmonic distortion of 0.001% at 170mW (250ohm), unparalleled frequency response range of 1Hz to 100kHz, and high output power levels of 100mW at 600ohm. Considering that the signal to noise ratio is theoretically undetectable, that the A2 operates far outside the human range of hearing (which leads to a smooth presentation between 20Hz – 20kHz), and that anything above 50mW of power output (up to 600ohms) is an average comfortable listening level, then the A2, on paper, is an absolute powerhouse, although these specifications are almost identical to the previous generation A1 and still has an high input impedance and low output impedance to not draw any current from the input and thus preserve the input signal.
Where the difference is between the A1 and A2 headphone amps obviously shows itself with an addition ¼” headphone output and fully discreet circuitry, but other additional features have been added in the form of an selectable output impedance and gain trim. With these new features the user can adapt the power handling to the headphones that they will be using. In its standard configuration the A2 has a 0 ohm output which works well with low impedance headphones with a rating between 16Ω and 32Ω, although the users can flick the switch and engage an 100 ohm output that works well with medium to high impedance headphones (anything from 80Ω to 600Ω). Finally the switch below the selectable impedance is essentially a safety and convenience option. This gain switch adapts the Beyerdynamic A2 to the typical headphones that the user will be consuming, so at 0db this will work well with medium efficiency (or ohm rating), -4db will work well with sensitive headphones (or low ohm rating), and finally +6db for when operating high resistance headphones (high impedance). Either way, this is a useful addition.
Before continuing it is important to clarify that prior to use the Beyerdynamic A2 underwent an hour warm up time and the signal path. For this review we used an Apple MacBook Pro, lossless tracks from 16bit 44.1kHz to 24bit 384kHz, played via Sonic Studio Amarra in standalone mode, connected to a Chord Electronics Hugo, Lynx Hilo, Prism Sound Lyra 2, CAD 1543 DAC with a CAD Premium USB, The Chord Company Signature Tuned ARAY RCA, and Beyerdynamic T90 headphones, NAD VISO HP50 headphones, Audio Technica ATH-M50 headphones, Musical Fidelity MF-100 headphones, and Beyerdynamic DT250 headphones.
In contrast to some of the physical design issues experienced, the A2 is a brilliant sounding headphone amplifier with an impressive eye for detail and a beautifully transparent soundstage. In use there is absolutely no audible distortion within the signal path and the resulting output appears uncluttered and free of any applied harmonic artefacts to the original waveform. Another positive aspect is that the A2 has an excellent transient response, and this combines with the above to produce a neutral ‘realistic‘ sounding unit where the highs are crystal clear and sparkly, the mids are smooth and texture rich, whilst the lows are deep and punchy. The A2 certainly appears to be as inoffensive as possible by not aiming to mask or ‘treat’ the audio, but to just amplify the signal in a way that retains the original sound, life, feel, and beat of the music. The result of this does mean that the A2 is brutally honest with the tracks that you play through it and does have a habit of showing up poor recordings or lossy file formats. Regardless, the fact is that the A2 is an audiophiles dream with the correct source components.
Often when branding a headphone amp with the term ‘neutral’ it is all to easy to misunderstand the compliment by assuming that the performance is lifeless of lacks character. Whilst this is completely understandable and does accurately describe other units, the Beyerdynamic A2 is far from this. For example, with the correct source, the A2 enables the music comes alive and gives you a very nice representation of spatial awareness where sheer depth is explored by a vast back and white background and foreground without biting or fatiguing the ear. In practical terms the A2 brings a recording to life by delicately presenting artefacts such as fingers sliding their way up the frets, the movement of the artist, and actually presenting science in a mix with science; a simple thing, but difficult to achieve.
Despite the permanent orange glow emitted from the top plate ribs, the Beyerdynamic A2 headphone amplifier is a brilliant neutral sounding solid state headphone amplifier that is inoffensive, beautifully engaging, and addictive to listen to. The absorbing powerful yet delicate performance works well with a whole host of headphones and music genres. Regardless of the upgrades that make the A2 a much more competitive headphone amplifier over the A1, the contradicting physical design along with limited inputs and a dual parallel ¼” headphone outputs only allow us to issue the Beyerdynamic A2 with a four out of five rating.