Veteran makers of studio headphone amplifiers, Manley Laboratories takes on the extreme high-end of the home genre with a £4,500 unit, the absolute one, combining the sonic requirements of audiophiles with the total control demanded of professionals . The company’s CEO, Eveanna Manley, puts it bluntly: “Our goal was simply to produce the most impressive-sounding and most sonic-flexible vacuum tube headphone amplifier.”
To address consumer use, the thing looks great and is designed to sit proudly on a desk, nightstand, or anywhere else the headphone amp can be placed. Unlike manley’s lab-looking stuff for studios, the absolute is made with a chassis sculpted from solid in three colors: black, copper, or silver. hand-rubbed walnut veneer covers the headphone rest areas, doing the absolute double as a stand.
Reading: Manley absolute headphone
manley avoided installing a dac, and eveanna explained: ‘we already have a lot of features built into this unit. furthermore, a better dac can be designed in a larger chassis, with a dedicated power supply to make it fully featured. we never set out to cram a dac into this form factor, or install a bluetooth receiver’. As for the wireless technology, she added, laughing, ‘We’ve provided an amazing RF wireless remote control!’
set ‘n’ match dac, this is hands down the best equipped headphone amp I’ve come across. I can’t, by chance, name one that does everything the absolute is capable of, although the audiovalve solaris comes close. As is the norm at this level, the Absolute accommodates balanced via xlrs and normal headphones with ¼ inch connectors, and can be used as a preamp thanks to rca line level outputs and two pairs of rca inputs for line sources. So far so normal.
manley says the device provides ‘fifteen independent controls’ and I tried them all. With the exception of balanced headphones which require two xlr or two ¼ inch connectors, the intention is to be able to combine this with any headphone on the market. The volume control on the fascia is a horizontal thumbwheel to bring tears to the eyes of those who remember vintage Marantz FM tuners. to the right is the mute button, to its left a button to choose between push-pull or single-ended tube modes.
This unit, better than any other I’ve tried, allows you to experience without hesitation the differences between the two topologies, while teaching a valuable lesson: they are not mutually exclusive, so absolutists should put a sock on it. you’ll find yourself ‘learning’ what suits which headphones, types of music, or, when used as a preamp, which power amps. the variations are subtle but decisive and go a long way in optimizing the performance of the headphones.
the volume is indicated by a row of 16 white leds on the thumbwheel, with steps of 127 x 0.5 db. then come five buttons and four knobs at the top of the front section. knobs control (left to right) headphone load, set via custom output transformers crafted in-house, with low (l) settings for 12-50 ohms, mid (m) for 50-200 ohms and high (h) for 200 -600 ohms and above.
into the valley balanced (xlr) and single-ended (¼-inch jack) headphone outputs are selected along with the rca preamp output. the middle button selects either of the two line inputs, the next button toggles stereo/mono, and the last button is the EQ control that activates or bypasses the tone controls. again, white leds indicate all options.
Above these buttons are four tall, thin spinners. from left to right there is a ‘feedback control’, its use affects refinement levels. the two knobs in the middle are treble and bass controls, activated or bypassed by the eq button. Lastly, the balance control provides a 72db swing each way, with a center detent that takes it out of the loop.
Next come two 12ax7 inlet valves and four 6aq5 outlet valves, wired as triodes, housed in the valley formed by the metal sides. on the back, next to the rcas, is a small rotary knob for “headphone protection control”. inactive when turned fully counterclockwise, can be used to set a threshold to protect expensive headphones (or hearing) from overload, by monitoring the output level and automatically lowering the volume when exceeded the user’s threshold.