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Such an accurate, fast and dynamic sound could be easily ruined by not being backed up with something other than detail, something that's behind the sound of basic instruments. The AMP-11R simply doesn't make those mistakes though it's not perfect. Some things it can't do. It shortens decays a bit and focuses the sound between the speakers without clear expansion beyond. Extreme punch, bass extension and a sense of absolute power or fullness are out of the question. Nevertheless the Bakoon is a terrific surprise which makes music listening a most joyful endeavor not in spite of anything but clearly because of its very specific design choices.

AMP-11R + headphones. This wasn't the first time I've dealt with a situation where very good or in some regards truly spectacular sonic qualities of an integrated amplifier translated intact into the realm of headphone amplifiers. Previously this happened with the Leben CS-300 X custom version and two amplifiers from Cary Audio, the CAD-300-SEI and SLI 80. Every now and then I would also have very good results with certain preamps and digital players but when it comes to absolute reference sound, such finds have been rare.

All the more surprising it was then when I connected headphones to the AMP-11R. I could not believe the sound with the HiFiMan HE-300 and HE-500 but most of all their top HE-6 which until then had only suggested their true potential. I have listened to the HE-6 with over dozens of amps. Only in a few cases did I approach somewhat of a full response which nonetheless would always be limited and conditional still. The AMP11R and HE-6 now made for a unique combination without need to justify or qualify anything.

Sitting comfortably with our Fang BIan headphones over the ears, we will hear sound that on one hand is energetic and beautifully sorted, on the other calm. The combination of these two qualities marls the very best of designs. In others the makers usually try to polish one or the other. Here we get both. This headfi system also consisted of the Human Audio Libretto HD CD player and Klutz Design CanCan headphone stand (an integral part of my auditioning system). It was almost as perfect as my current reference and in some ways superior to the Leben CS-300 X paired with Sennheiser's HD- 800. The Leben and Sennheisers exhibit more saturation in the bass and low midrange but the sound is also a little more moist and not as clean as that of the Korean amp and American/Sino headphones.

The speed of these particular magnetostatic headphones combined with the extremely wide bandwidth and precision of the Satri circuit resulted in something that transcended the usual discussion of treble, bass and midrange. It opened up another dimension. If I perhaps missed something of the greater calmness of the Leben and Sennheiser combo, I had no problem transition from one reading to the other. Over time I noticed myself spending more and more time with the HiFiMans on my ears. It was only the narrower more centrally focused soundstage of the Bakoon/HifiMan combo which markedly differentiated both systems in favor of the Austrian/Japanese duo.

Because the HE-6 made such a powerful impression, I spent far less time with other headphones in my collection. I still did my homework however and found certain combinations which I can recommend with a clear conscience and would be happy to use myself every day.


HiFiMan HE-500: Very fast sound, powerful low bass with high transparency. The sound was focused in the center of the head and emphasized around several kHz. Generally everything seemed far more compressed than with the HE-6.

HiFiMan HE-300: Much better synergy than with the HE-500. The sound was saturated and full with slightly contoured frequency extremes but nothing exaggerated. The low bass was powerful and cymbals richly detailed without brightness and perhaps even a minor withdrawal at the very top. The midrange felt somewhat papery and not fully saturated but overall this was a very satisfying combination.


Beyerdynamic DT-770 Pro Limited Edition 32Ω. Overall less saturated than the HE-300, this take was more distanced and less tangible. The low end however was smoother and better differentiated as was the treble. The latter was more open if not as exploded as with the HE-6. A slight emphasis in the upper midrange produced freshness and panache but no sharpness or brightness. The combination was interesting but not for me.

Beyerdynamic DT-990 Pro 600Ω: Oh baby! How great these headphones are despite being about 15 years old. Their ear cushions had been replaced a few times already but the diaphragm and all other components were original issue still. This was tonally most balanced throughout even if not as selective and defined as the Sennheiser HD800 and HiFiMan HE-6 to which it couldn't stand up. Still it was most balanced and only slightly gave up saturation and directness to the HiFiMan planarmagnetics. Regardless I could enjoy this without fatigue for hours.


AKG K70: A surprisingly successful combination. It wasn't the most detailed and differentiated sound but had excellent dynamics and vibrancy. Both frequency extremes were withdrawn but the mid treble and upper bass were firm and fleshy. Images were close up, tangible and solid. A real surprise.
One channel's discrete current-mode op-amp Satri module
AKG K271 Studio: This had a clear withdrawal of treble, lack of low bass and a stronger emphasis on midrange attacks. Overall the sound was pretty good and balanced if a bit 'plastic' by lacking saturation and tangibility. On the other hand there were no treble problems which plague many other. A classic that still held its own.


Sennheiser HD800: This sound was almost on par with the HE-6. This combination didn’t have quite the resolution and selectivity of the planars but bass seemed better and more full-bodied. The tonal balance center was set higher than with the Leben and showed a slight emphasis around several kHz but without serious consequences. This was a really great system that I'd recommend to anyone!