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Reviewer: Srajan Ebaen
Financial Interests: click here
Source: 1TB iMac (AIFF, WAV and ALAC) with PureMusic 1.72 in memory play via USB into Burson Audio HA160D or via FireWire into Weiss DAC2 - Ancient Audio Lektor Prime and Raysonic Audio CD-228 as legacy backup decks
Preamplifier: Bent Audio Tap-X (remote-controlled AVC passive), StereoKnight Silverstone Balanced [on review]
Amplifier: FirstWatt F5 and J2
Loudspeakers: ASI Tango R, Boenicke Audio SLS, Zu Audio Essence
Cables: ASI Liveline
Stands: 2 x ASI HeartSong 3-tier, 2 x ASI HeartSong amp stand
Powerline conditioning: 2 x Walker Audio Velocitor S, 1 x Furutech RTP6
Sundry accessories: Furutech RD-2 CD demagnetizer; Nanotech Nespa Pro; extensive use of Acoustic System Resonators, noise filters and phase inverters
Room size: 5m x 11.5m W x D, 2.6m ceiling with exposed wooden cross beams every 60cm, plaster over brick walls, suspended wood floor with Tatami-type throw rugs. The listening space opens into the second storey via a staircase and the kitchen/dining room are behind the main listening chair. The latter is thus positioned in the middle of this open floor plan without the usual nearby back wall.
Review Component Retail: €2.300 + €990 for optional external power supply, €150 for remote control (also works the CDP)

Today's review arose from a no but scenario. Push/pull in audio lingo. Here's the actual exchange. "Dear Srajan, my name is Krisztian Neukum. We recently launched the Human Audio brand. We are a very small team with ambitious dreams, strong passions and very qualified experts. Our first goal was to eliminate all power utility interference. We tried several filters and power reconditioners without being completely satisfied. When we built the very best possible PSU and compared it to battery operation, we still felt the difference in favor of batteries was disproportionate, hence our company focus became pure battery drive. The other obvious benefit is performance invariability. Based on experiments, AC power quality varies very much with location and load (how far one is from the power delivery step-down transformer on the street, how old the building/cabling is, whether it's daytime or evening). With batteries, our equipment sounds the same everywhere anytime.


"Our first product concept was to develop a unique fully battery-powered CD player which would reach the ultimate performance in digital audio. In our opinion we have succeeded now. The first Human Audio product is the Libretto. Separate batteries power the digital and analog circuits. We even avoid a DC/DC converter which would cause its own interference. The battery monitor and charger are fully automated to require no user supervision whatsoever. Then we had to identify the best currently available CD mechanics. That was relatively simple since very few top-quality makers of transports are left. The chosen Philips Pro2 industrial transport mounts rigidly to the chassis. Instead of oscillating springs, spongy rubber and similar suspensions, all vibrations are redirected through special lenses while the bamboo enclosure functions as a truss. We believe the right clocking stage to be very important so the Libretto contains a very accurate clock circuit from a famous expert. The digital output stage (optional coaxial or XLR) is unconventional too. Since we don't like the popular 'big iron' approach to hifi, we decided to build the housings from natural materials. Unlike metal, bamboo is very warm and green. This kind of tree is cultivated for industrial purposes so one needn't decimate dwindling natural resources. Bamboo actually is the fastest growing tree in the world.


"Also keep in mind that power consumption/efficiency are important contributors for green behavior. We have plans to provide an optional Human Audio solar charger to provide the utmost in off-the-grid operation for our gear. Back to the Libretto, its hybrid DAC uses a very sophisticated analog circuit and specialized 0.05Hz to 10MHz Jensen transformers. The driver stage to the transformers is entirely free of negative feedback. Analog outputs are 600-ohm XLR and RCA connectors. The enclosure is available in a variety of plywoods or bamboo. Because we have worked in the audio world for a very long time, we usually read your news and reviews pages and know your site to be very objective, friendly and fair. How can we get a comprehensive review of our CD player?"

Taking a look at their Hungarian website and despite the Libretto looking very scrumptious indeed, we next hit a snag. That's because wearing my staunchest consumer protection cap and standing tall on the "high-end flushed itself down the toilet and keeps on flushing" soap box, I noted that the machine lacked digital inputs. As a 2010 release, there was no bridge to PC audio. Krisztian confirmed it. "We are presently working on an upgraded version which will have a USB 2.0 port. We have no current ETA however because we must first develop an entirely different D/A converter stage. The present one is limited to 16-bit resolution."


With an ambitious MSRP of €6.990 plus VAT (including a 5-year warranty with 2 years for the batteries and lifetime technical support), I didn't feel right rewarding with a formal review crippled functionality regardless of how good the machine might sound. Functionality is part of good performance. Comprehensive engineering ought to account for it all. There's also the investment aspect of fine hifi. Consumers shouldn't end up with unsellable properties.

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