Headphones

One more thing: Manley's remote volume control is handy if you run long headphone leads and are not seated next to the Absolute. As it operates over RF it has a far longer range than an IR control, and does not require line-of-sight to the Absolute. It's particularly useful when the Absolute is used as a standalone preamp.

Doing The Can-Can
I tried 12 wildly disparate pairs of headphones from Sennheiser, Audeze, Master & Dynamic, Beyer and others, balanced and single-ended, and of various impedances. Thanks to the adjustability of this unit, I must now admit that I am no longer satisfied with anything less for critical headphone listening sessions – let alone for reviewing purposes. What is not as clear-cut as one would hope is merely setting the headphones to L, M or H according to the factory-specified impedance. I found, for example, one model rated at 32ohm smoother with the M setting than with the 'correct' L position. My preferred Audeze LCD-4z, rated at 15ohm, categorically sounded best, regardless of the material, at the 'L' position, with the connection balanced and the feedback in the middle. Then the fun started.

Manley is not absolutist about the settings of the Absolute and recommends experimentation, but the excitement comes with comparing push-pull with single-ended operation. As with power amplifiers of both topologies, push-pull promises more grunt or kick, and single-ended ought to sound sweeter. We have believed this mantra ever since SETs reared their 300B-filled heads a few decades ago, so I am relieved to report that the Absolute perpetuates this received wisdom. All it took was the superbly recorded live release of Paul McCartney's Amoeba Gig [Capitol 602577289767 CD], to confirm that this switch will turn you schizophrenic.

How so? Because the magnificent percussion and bass were tauter, drier, with more impact on the push-pull setting, most notably on 'Get Back', while the space and openness were more convincing in single-ended mode, as expected. This varied by degrees from model to model, the Audeze headphones more revealing of the nuances, while the Sennheiser HD414s were less susceptible.

Sonic Bliss
McCartney's intimate performance, which took place in a record store in the USA, has some of the most convincing audience sounds I can recall – no Rice Krispies applause here – and this exploits the Absolute's greatest sonic virtue, its openness, once you've found the right groove for the myriad settings. With the closed-back, 20ohm Audeze LCD-XC 'Hey Jude' reached optimal sonic bliss with the impedance low, via XLR, the feedback off and the mode single-ended.

Turning to the 32ohm Master & Dynamic MW40 via its ¼in jack, I preferred the same recording with the settings on push-pull, mid-point on the feedback and impedance on M. And if this sounds like a recipe to drive you crazy, remember that 1) you probably aren't trying it with myriad headphones, maybe just one or two pairs because you're a normal person, and 2) you will find overall settings that suit the majority of your listening. Conversely, if you are the obsessive type, you will not be able to resist fiddling with the controls regardless.

Top Sounds
Back to the Audeze LCD-4z: with feedback in the middle, impedance on L and frequently switching from push-pull to single-ended, I delved into a ZZ Top-fest, the Goin' 50 3CD set [Warner Brothers R2 591567], revelling in some of the best-recorded drum sounds imaginable. In fact, I left the opening to 'Gimme All Your Lovin'' on repeat just so I could continue comparing the two. Surprise, surprise: as much as your conditioning wants you to prefer push-pull for maximum impact of Frank Beard's sublime percussive artistry, the SET position somehow added to the authenticity, especially for those attuned to hearing the 'stretch' of the drum skins.

This is not, I hasten to add, the curate's egg I seem to be describing – the only reason everything seems so exaggerated is down to the simple fact that headphone listening exacerbates any weaknesses in a playback chain. Why? Because the listener suffers no distractions and is thus more focused. In every case, despite my stressing the illustrative value of percussion, vocals reveal the most when playing with the settings. The contrasts may be so subtle that they would elude casual listeners, but for you they will be clear as day.

Which tells you something else: the Absolute is not aimed at the casual listener. Rather, it is categorically conceived to serve the needs of the cognoscenti. And it succeeds mightily.

Hi-Fi News Verdict
No reason to mince words: this is the best headphone amplifier I have ever used, and not just because of its total adjustability and design brilliance. Even with median settings (eg, for feedback) rather than fine-tuning to the max, and regardless of which headphone I used, it is the most neutral, open, nay, musical headphone amp I have tried. If I wasn't a cautious pensioner, I'd buy one. Absolute? Absolutely.