Feliks Audio Envy Review

The Envy – Design


Electrical design

On the input there is Alps Rk27 potentiometer, followed by two-stage pre-amplifier with CV-181 tubes and coupling capacitors Jantzen Superior Z-cap. There is a slight left/right channel imbalance at the very lowest volume level but any normal listening level, there are no issues with the ALPS. Power tubes are the directly heated 300B tubes. Output transformers are custom made hi-end audio units (made by EDIS Ogonowski). Mains transformer is also an audio grade unit by EDIS.

The amplifier has fully automatic bias and its electrical circuit is a “zero feedback” design. The power tubes are heated with direct current (DC) with a special circuit designed to separate the tubes heating from audio path powering. Power supply for anode voltages is designed on semiconductor and based on MOFSET transistors and low-noise current sources.

On the XLR balanced inputs, symmetrical audio grade Lundahl transformers have been used. Audio sources selection is made using high end relays (low signal relays), which are placed directly behind the input connectors, in order to limit interference and noise.

The amplifier is made using “point to point” technology. All wired connections are custom made from single crystal copper (UPOCC) with a Teflon isolation.

Starting with the real purpose of “impedance” selector on the amp – in practice this selector limits the output voltage that gets to the headphones. At Low it’s limited to 2V, at Mid to 9V and at Hi to 16V. These are voltages “without load” and they go slightly down when appropriate load (in this case a headphone) is connected, based on their impedance. For example, if you connect headphones with 32ohm, this 16V will drop to about 14V.

The above (see impedance settings) also explains the difference between OTL (e.g Euforia) and non-OTL (Envy). The Envy can sustain much higher voltage and current (therefore power) – for example Euforia can deliver only about 4V (with no load) compared to 16V of Envy (no load). This is why dynamic headphones are so good with OTL – they don’t need high voltage to drive them well.

Feliks Audio Envy

External Design

The amplifier is built on a solid metal chassis and finished with a natural high-quality oiled wood. You can clearly see that in the pictures with the horizontal division/line the amp has all around. Beautiful. As said, my version is the American Walnut wood and it looks stunning. Do note that the oil the wood has been worked with has quite a bit of a smell to it, so in a closed office you will certainly smell and notice it for quite a while.

Envy has that high-end look and feel and it looks powerful, robust and yet refined and precious. The only way to upgrade the looks of the amp even more would be to get some really nice mesh style 300B tubes, but ok. That’s quite the investment to make for just the looks.

So yes, I really like the design of the amp. It actually is quite compact for such a monster. The Envy measures 35 × 33 × 18.5 cm and weighs an impressive 15.1kg. It sits extremely sturdy on your desk and it won’t budge when connecting or unplugging cables and headphones. Carrying it up and down the stairs from one office to the other, is not really recommended.

Design-wise I find the Envy to have a modern and refreshing look. There’s a nice symmetry and excellent use of available space on the top, front and back. Using the Envy is very straightforward, even if the double power button can be confusing for first time users. The main power switch is at the back, while you have a touch sensitive stand-by button with an LED indicator on the front top. For a full “power off” of the amplifier Feliks Audio advises to use the physical switch on the rear panel of the amplifier, near the AC connector.

Build quality wise you at this level expect a lot and the Envy delivers in abundance. We’ve already discussed the internals earlier but also on the outside everything is superbly finished with top quality materials. I like the big ALPS volume dial, it’s smooth to “roll” and very precise. All the connectors and switches on the front and back also ooze quality. This amp will probably survive you without it ever needing any maintenance. Personally, I am not fan of the vertical input tube protectors, so I never installed the grills (as the pics show). These grills come included so it’s totally up to you if you want to “put them on” or not. Tubes do get hot, so pay attention. Cats and kids usually find out the hard way if you’re not careful enough.

The oiled wood is really nice to look at, and I am very pleased I got the American Walnut version. It’s so classy.

A small thing I really appreciate is how the tube sockets are placed. That in combination with the consistent labelling on the tubes makes sure the tube name/logo is always facing front. Love it.

Feliks Audio Envy

Box and Packaging

The Feliks Audio Envy comes in a big box in which the amplifier and the tubes are perfectly protected. As usual, Feliks Audio is using cut-out foam, specifically cut out for the Envy and the tubes. That means your unit and the tubes will arrive perfectly safe at their destination. Top marks for Feliks Audio regarding their shipping, many companies can learn from this.

On the inside of the box you will find your Envy, a matched pair of driver tubes CV-181(6SN7), a matched pair of power tubes 300B, an AC cord, a user manual (even if our sample didn’t) and a warranty card.

Simple but effective and complete. Just make sure to carefully clean the insert residue from your amp and tube sockets.

Amplifier Lay-out

On the front you from left to right find: the XLR output, the 6.35mm output, the ALPS volume dial (smooth but slightly resistant), the impedance selector and the input selector.

On top you on the front center have the touch control/power button with the incorporated LED. Next to that you on both sides have the input tubes (and the grill/protection if you opted to install it) and the 300B tubes are on the outside. At the back of the unit you have the matte black transformer protection with the Feliks Audio logo and name. Classy.

On the back of the unit you from left to right will find the power plug and main power switch, both the unbalanced RCA inputs with the XLR input below and then the RCA and XLR pre-amp outputs.

As you can see in the pictures it looks elegant and it’s functional with more than enough room to plug in larger aftermarket cables.

Feliks Audio Envy

The Full Specs are below. The article itself continues on the next page. Click here if you don’t care about the Specs.

Full Specifications

Class A Single-ended transformer coupled amplifier

Power tubes: 300B

Driver tubes: PsVane CV-181 mk2 (6SN7)

2x unbalanced RCA inputs (IN1, IN2)

1x balanced XLR input (IN3)

Input sensitivity 1V RMS

Input impedance:
– For IN1 i IN2 (RCA) 100kΩ
– For IN3 (XLR) 10kΩ

1x pair of pre-amplifier output as RCA

1x pair of pre-amplifier output as XLR

Maximum voltage on the above outputs is 5V (RMS) at output impedance of 600Ω and THD<0,5%

Impedance selector guidance:
– LO – up to 60Ω
– MID – up to 300Ω
– HI – up to 600Ω

Amplifier’s impedance:
– LO at 32Ω load is 3,8Ω
– MID at 100Ω load is 8,8Ω
– HI at 600Ω is 20Ω

Output powered measured at MID impedance setting at load of 16Ω is 5W with THD ⩽1% (maximum 8W at THD >5%)

Frequency response:
– 8Hz÷100kHz ±3dB
– 18Hz÷40kHz ±1dB

Headphone outputs: 6.3mm and XLR

AC voltage 50/60Hz:
– 230V version (±5%)
– 115V version (±5%)

Power consumption: 110VA

Weight: 15,1kg (without packaging)

– 35x33x18,5cm (LxWxH) – without tubes
– 35x33x24,5cm (LxWxH) – with tubes


Page 1: Feliks Audio, Envy, Features & Options, Driving capabilities & Impedance settings, Tube Galore

Page 2: Envy Design, Box & Packaging, Lay-out, Full Specs

Page 3: Sound – Intro, General, Basics, Headphones Pt.1

Page 4: Sound – Headphones Pt. 2, Comparisons, Conclusion

4.4/5 - (98 votes)

Lieven is living in Europe and he's the leader of the gang. He's running Headfonia as a side project next to his full time day job in Digital Marketing & Consultancy. He's a big fan of tube amps and custom inear monitors and has published hundreds of product reviews over the years.


  • Reply May 30, 2022


    What you can say about this amp with the Susvara?
    The vocals and midrange are still intimate and lifelike you think?
    and with the ability to breath and so on.. or that is not put too much focus on this regard?

    Also about the LCD-5 – what you think about the midrange/vocals with this amp?


  • Reply June 3, 2022

    Mohit jain

    Thanks for an excellent review!!

    I was thinking of just one question in mind that if Auris Headonia and Feliks Envy are more or less on same level then what about Auris Nirvana, does Feliks Envy surpass the Auris Nirvana, especially in pairing with Susvara by a mile ?

    • Reply June 5, 2022


      In pure power it does not, but technically it does. It’s more refined

  • Reply September 3, 2022


    Which impedance selector position do you recommend placing when paired with the Audeze LCD-5?
    Thank you for your attention !!!

    • Reply September 3, 2022


      In general I would recommend low gain, but it depends on the combo and how you “like” your LCD-5 to sound. Just use whatyou feel sounds best

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