Feliks Audio Echo Review – Proposition

Felix Audio Echo review feat new
TESTED AT €499.00 ( $445 )

Are you looking to put some musicality back into your digital music? Then this could be just what the doctor ordered. In today’s review, I’m checking out the Feliks Audio Echo tube amplifier. The Echo is a handmade output transformer-less (OTL) headphone amplifier and preamplifier that has two 6N6P power tubes and two 6N1P driver tubes. This amp has a sweet, dynamic and robust sound signature that can really bring your music to life.

Feliks Audio is a family company based in Lubliniec, Poland. They’ve been developing and manufacturing tube amplifiers for over 10 years and all of their products are engineered and assembled on-site.

Feliks Audio website: http://feliksaudio.pl/

Music is the harmonious voice of creation; an echo of the invisible world.

Giuseppe Mazzini

This sample was provided for the purpose of an honest review. All observations and opinions here are my own based on my experience with the product.

Feliks Audio Echo Review

  • Beautifully crafted case
  • Pure, clean sound with black background and no hiss
  • Simple, elegant design

  • Unit gets quite hot

Build Quality and Design

Feliks Audio Echo top-down view.

The Echo’s chassis is made of sturdy solid metal with real wood side panels. The wooden panels along with the tubes give the appearance a hint of retro encased in a timeless minimalistic body. Despite being Feliks Audio’s most affordable model, the Echo looks and feels unquestionably premium.

The front panel holds the 6.35mm headphone output and large Alps potentiometer in the centre. And what a knob it is (insert coarse humour here!) It has a lovely smooth and weighted action that feels perfectly suited for this robust device.

Around the back, the Echo’s rear panel consists simply of RCA IN and OUT connectors, plus the power socket and power switch. The Echo can be used either as a headphone amplifier, preamp or directly powering active speakers.

The back panel with it's RCA IN and OUT connectors.

Vents on the top and bottom of the unit allow for some of the heat to dissipate but the chassis still gets plenty warm. While it’s all within tolerable limits, it’s recommended you give the Echo a well-ventilated space.

One final thing to note is that the Echo requires a little time to reach its full potential. According to Feliks Audio, it takes around 15 minutes after switching the amp on before it reaches its optimal state.

Power Output

Echo’s power output is rated at a hefty 350mW which should be enough for headphones up to 600 ohms. Despite its impressive power reserves, the Echo is extremely quiet and boasts a very low noise floor.

Even though Feliks Audio recommends headphones with a minimum of 100 ohms, I’ve had absolutely no issues using low-impedance headphones and even sensitive in-ear monitors. Regardless of what I plug into it, I am rewarded with a pure, clean sound and a silent background with no audible hiss. Who doesn’t love it when a product under-promises and over-delivers?


Closeup of the Feliks Audio Echo's front panel.

Gear used for testing:
Source: Singxer SDA-2.
Headphones: Beyerdynamic DT990 Pro, Acoustic Research AR-H1, BLON B20, Hifiman Sundara, Thieaudio Phantom

At first, I was a little concerned that the Echo wouldn’t find a good synergy with many of my headphones since most of them are planar dynamic and are less than 100 ohms impedance. I needn’t have worried though because everything I paired with it performed beautifully, even in-ear monitors.

The Echo imbues the sound with a hint of extra warmth and earthy naturalness. It sounds richer, smoother and more organic. Bass gains a little fullness and body but the Echo keeps it clean and pristine, preserving texture and definition.

Feliks Audio Echo hooked up to the Singxer SDA-2 DAC.

Like the bass, the midrange is lush, opulent and full of nuance and texture. There’s no loss of fidelity or resolution, just a natural warmth that gives the music an inner glow. It reminds me somewhat of the Arcam irDAC-II with its smooth character and rich detail but it has a more dynamic and lively feel.

The Echo adds sweetness to the treble without dumbing it down or losing any detail. Hi-hats and cymbals sparkle and are rendered with extra air as if they’re feathered lightly. Note density is left intact and the treble is never left feeling too diffuse or washed out but some of the edge is taken off, which is perfect for brighter headphones.

All this takes place on a blissfully black background. The Echo has been crafted with premium components to keep the noise floor at a minimum and this is especially noticeable when using sensitive headphones or in-ear monitors. It provides pure, clean power, a touch of warmth and an organic sweetness that I have not heard with any of my other headphone amplifiers.

Feliks Audio Echo with the BLON B20 headphones.

The Feliks Audio Echo has a wonderfully expansive soundstage. Both width and depth are increased when using this amp as the 2nd order harmonics introduced add subtle bloom and spaciousness to the sound. Notes become fuller and more substantial, occupying a larger space but with increased air in between. This is especially impressive for such a smooth-sounding amp as we normally associate smoothness and extra warmth with a reduction in stage dimensions.

Acoustic Research AR-H1

The AR-H1 is a planar magnetic headphone with a very clean sound that is neutral leaning towards bright. If ever there was a perfect candidate to pair with the Echo, it would be something like this. The Echo imbues it with a light warmth and fills out the AR-H1’s midrange, giving it extra body and fullness. It still sounds bright at times but some of the edge is taken off the upper mids and treble and the presentation is a little more relaxed.

Hifiman Sundara

Hifiman’s entry-level planar magnetic headphone sounds brilliant when hooked up to the Echo. The tone is natural with a warm lower range and neutral midrange. The Sundara’s bass really seems to fill out more than my other planar headphones with the Echo. It feels softer but has more weight behind it.

Vocals are rich and clear and the midrange resolution is fantastic. The Sundara already has a pretty relaxed treble but it’s even smoother with the Echo, although the extension is still there. The soundstage sounds very organized and stable, not as holographic as the AR-H1 but still impressive for a planar phone.

Feliks Audio Echo with Hifiman Sundara headphones.

Often mentioned alongside the Sendiy Aiva, the BLON B20 is another planar magnetic headphone with a lovely clean sound and good dynamics. Its midrange is more upfront than the AR-H1 but it doesn’t have as large a soundstage. Pairing with the Echo adds depth to the stage, making it feel more immersive and spacious.

The bass feels more punchy but still very tidy and controlled. The Echo makes the B20 sound more robust and instrument notes have a larger girth from the light infusion of warmth. String instruments like violins and cellos sound really lovely with this combination. They sound pure, uncompressed and very natural.

Beyerdynamic DT990 Pro

Okay, it’s really about time I got some dynamic driver action up in here. Earlier I commented on how the Echo seems to work well with everything but this combo just blew me away. I’m actually tempted to go online and buy another pair high-impedance dynamic headphones just to use them with this amp.

I’ve had these Beyer headphones for years and tested them with lots of different configs and the only time they sounded this good was with the $4000 Phatlab Phantom (review here). If that doesn’t give you an indication of how good value the Echo is then nothing will.

The bass drives with authority and command, digging deep and hitting hard. Vocals and midrange instruments are clear as day and emboldened with extra body. The 990 Pro’s contentious treble is still lively but it’s a bit more mellow and noticeably sweeter when warmed with the Echo’s influence. I’m struggling to add the finishing touches to this review because I’m enjoying my music so much with this pairing right now.

Feliks Audio Echo with Acoustic Research AR-H1 headphones.


Every now and then, I come across a product that delivers more than expected and this is just how it is with the Feliks Audio Echo. It’s difficult to put into words just how good this amp sounds and it really does take my headphones to another level.

In addition to the audio quality, the hand-crafted unit is exquisitely built to exacting standards using only the best components. Just like its sound, the build quality of the Echo is something you need to experience first-hand in order to truly appreciate it. The mix of glass, steel and wood is a treat for the eyes as well as your ears.

If you are on the lookout for something to elevate your headphone experience and crave a natural, warm and dynamic sound I can’t recommend the Feliks Audio Echo highly enough. It has become an integral part of my desktop setup and won’t be moving anytime soon.

  • Power tubes 6N6P x 2, driver tubes 6N1P x 2
  • Frequency response: 15 Hz – 45 kHz +/- 3 dB (300 ohm)
  • Input Impedance: 100 kOhm
  • Power output: 350mW
  • THD: 0.4 % (300 ohm, 20 mW)
  • Optimal headphones impedance: 100 – 600 ohm
  • Preamp safe mode
  • Headphones output: Jack 6.3mm
  • RCA audio input
  • RCA audio output (pre-amp)
  • AC: 230V/120V (power cord included)
  • 2 years warranty

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1 year ago

Hello, great review. I use a lot of IEM’s and a tube amplifier my main setup. Does this work with IEM’s? The ones I use most are Fir Audio Neon 4.
Many thanks$Bert

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