Purifi 1ET400A based Stereo Amplifier

PURIFI 1ET400A based Stereo amplifier – Powerful and precise

Apollon Audio PURIFI 1ET400A SLM Stereo Amplifier incorporating the award winning PURIFI 1ET400A amplifier module. Delivering power for the most demanding studio, PA or audiophile speakers with amazing clarity and brutaly honest linear sound.

Thrilling sound experience with our custom input buffer boards

The PURIFI 1ET400A based amplifier has the option to use a custom input buffer board with class A op amps that makes the PURIFI 1ET400A work to its fullest potential and create a mind-blowing musical experience. With our PURIFI 1ET400A Amplifier you have the option to choose our custom Apollon input buffer board built around Sonic Imagery 990 PRO OP Amps or Sparkos Labs SS2590 PRO op amps and Sparkos Labs regulators. The Apollon input buffer board is built using highest quality 1% metal film resistors and audiophile grade polystyrene capacitors, while the power is being conditioned with discrete voltage regulators made by Sparkos Labs.

very big soundstage and defined 3D sound

The stereo amplifier is handbuilt with highest precision using only highest quality components. To connect your speakers we use premium WBT 0703 CU or WBT 0703 AG (optional) Binding Posts that are internally connected to the amplifier with Neotech UP-OCC 12AWG Solid Copper Speaker Output Wire. The input connectors are Neutrik high quality silver plated XLR sockets. The stereo amplifier has a soft start function and it is turned on with an illuminated switch on the front panel. The stereo amplifier also has a standby mode, to turn it off completly a high quality mains switch on the backpanel is used.

The stereo amplifier contains a PURIFI 1ET400A module coupled with an Apollon Audio custom input buffer board. The PURIFI 1ET400A stereo amplifier is powered with a SMPS Hypex power supply boasting 1200Watts of power. The standby control module is powered with a low-voltage power supply unit.



Sparkos Labs SS78 & SS79 Discrete Voltage Regulators

Providing power to the Op Amps and the PURIFI 1ET400A, the Sparkos Labs SS78 and SS79Discrete Voltage Regulators play a key role for ultra low noise and fast transient responses on our custom input buffer boards for the PURIFI 1ET400A based amplifier.They are responsible for improved low level listening ability, far superior 3D soundstage and high frequency details. The difference is mostly noticeable at higher volumes, where the clarity remains on higher levels and with ample details and dynamics even at low listening levels.

The Sparkos Labs SS78 and SS79 Discrete Voltage regulators bring many advantages compared with standard monolithic designs where large capacitors for heavy filtering on the internal voltage can not be implemented. The fully discrete erorr amplifier on the device gives the ability for amazingly high input rejection and unique compensation techniques that are not possible to implement with regular monolithic IC error amplifiers.

Power rating

Watt @ 2 Ohm

Watt @ 4 Ohm

Watt @ 8 Ohm

Technical Specifications

True Mono Design
Frequency Response: 20 – 20kHz +/-.01dB
Low Distortion: THD+N – – 0.00017 % 20Hz
High Input Impedance 47K
Signal to noise ratio: 131db
26.5 dB Gain
Ultra High Damping Factor
Input Sensitivity 8ohm 2.52Vrms 10.24dBu
Power rating
: 450W @ 2ohm | 425W @ 4ohm | 227W @ 8ohm
Case Dimensions: 450 x 330 x 80 mm ( 104mm height with feet)
Weight: 8 kg


Hypex SMPS1200A400 (2 pcs.)
PURIFI 1ET400A amplifier (2 pcs.)
Apollon Audio Input Buffer Board (2 pcs.)
Apollon Control Board for standby control
Neutrik silver plated XLR line input socket (2 pcs.)
Gold plated RCA line input with switch (2 pcs.) – OPTIONAL
WBT 0703 CU binding posts (4 pcs.)
Neotech UP-OCC 12AWG Solid Copper Speaker output wire
12V Trigger Option for wakeup from standby – OPTIONAL
High quality fused mains input socket with power ON/OFF button
Aluminium enclosure with anti-vibration aluminium feet

Purifi 1ET400A Amplifier Module

Hypex SMPS1200 Power supply

Apollon Audio Input Buffer Board

WBT 0703 CU Binding Posts

Enclosure description and options

The Apollon Audio PURIFI 1ET400A amplifier case with the PURIFI 1ET400A module is very elegant and made of anodized aluminium. You have the option to choose a black or silver finish of the 10mm aluminium front plate aswell as black or silver finish of the aluminium feet.

Extended 2 years Full Warranty


 The Apollon Audio PURIFI 1ET400A stereo amplifier comes with a 2 Years Full Warranty. We are using only highest quality components and materials to build our Apollon Audio PURIFI 1ET400A  stereo amplifier based on the PURIFI 1ET400A modules. This selection by itself is a guarantee that the final product will stand the test of time and everyday use. Each PURIFI 1ET400A stereo amplifier is handbuilt with highest precission and care so we proudly stand behind our product and offer you a Full 2 Years Warranty.

Choose a discrete Op Amp that best suits your listening preference

Sparkos Labs SS2590 Pro discrete Op Amp

Listening impression and sound characteristics

The SS2590 PRO discrete op amps will outperform virtually all audio grade monolithic IC op amps in open loop gain, noise performance, output current, and magnitude of class A bias current. With comparison to the SI 990 disrecete op amp they are more soft, richer sounding and warm. They are your perfect choice if you would like to just sit back, relax and enjoy the music as everything just sounds so pleasing with the Sparkos SS2590 Pro op amp. If your current sound system lacks a spark of liveliness the Sparkos SS2590 is and ideal choice to bring a bit of warmth into your system.

Sonic Imagery 990 Dual Discrete Pro Op Amp

Listening impression and sound characteristics

The Sonic Imagery 990 is a dual high performance discrete operational amplifier designed for professional audio applications and areas where ultra-low noise, low distortion and highly linear uncoloured performance is required. It is a perfect choice if you have the professional need to analyse music or just like to explore the finer details. It will enable you to hear things like “oh the engineer eq’ed the piano too much or he over compressed the vocals” because they are very linear and analytical. It will make it possible to hear all the flaws in the mixes in a second.

What our clients say about the PURIFI 1ET400A

We are humble and do not like to brag, so below you can find just a few selected testimonials from our happy clients that own our amplifier built around the PURIFI 1ET400A amplifier modules.

“I had a pleasant surprise this evening. I had the visit of Johnny Cash and June Carter at my place and they performed an outstanding live performance. My all body was shaking and thrilled by the flow or their amazing voices and the rhythm of Johnny’s guitar.


This amazing experience was possible thanks to my customized NC1200SL I just received this morning. It feels like a quality product. It looks and sounds great. And it should further improve after few more days of listening.

The Apollon Team did a great job. The custom 8 connectors are perfect to bi-wire my B&W CM10. I was looking for the best value for money amplifier based on the Hypex NCore.

I am glad I found Apollon Audio.
I have to go. More guests are coming. The Folsom prison is inviting itself to my place. “

Nicolas Payen (Singapore)

“I’ve had the amp for about a week and a half now and I’m enjoying it quite a bit.  It’s opening up nicely and the depth and detail are excellent.  I’ve had to adjust my subs (dual Rythmik F15s) down a bit because, I believe, my Tylers are now being driven more to their potential. Excited to hear if things open up even more.

Very happy so far with my purchase.  Thanks again!”

Rich Stratton (Atlanta, USA)

“The amp sounds amazing. Everything you said about the amp is true. Super accurate, super precise and fast. I rediscovered my NS10s.”

Dominique Meyer (Switzerland)

“I received the amplifiers, I thank you again for the quality of manufacture. I will do a very good publicity for Apollon Audio.”

Cyril Khoudir (France)

What you get!

When you buy the Apollo Audio PURIFI 1ET400A SLM amplifier today you get:


A Handbuilt amplifier. The Apollon Audio PURIFI 1ET400A stereo amplifier is carefully assembled by hand.


Based on PURIFI 1ET400A. The PURIFI 1ET400A amplifier modules are one of the best performing class D amplifiers.


Hypex SMPS powersupply.  Providing 1200W of power is a key factor for sound dynamics.


OP Amp of your choice. You can choose the Sparkos Labs SS2590 or Sonic Imagery 990 Pro OP Amp.


Power rating. The stereo amplifier gives you [email protected], [email protected] and [email protected] of power.

RCA Line Input. Connect your equipment to the amplifier with RCA connection – OPTIONAL

Neotech UP-OCC 12AWG Solid Copper Speaker output wire adds more space and airiness.


WBT 0703 CU binding posts made of pure Copper; accepts banana plugs, spades, crimped cable ends


Low voltage PSU for waking  the amplifier from standby and make it more energy efficient and green.


12V Trigger for waking  the amplifier from standby and soft starting the SMPS power supply – OPTIONAL


2 Year Full Warranty The PURIFI 1ET400A amplifier has 2 years full warranty for any defects or malfunctions.


14 Day Money Back Guarantee Take your time to listen to the amplifier on your home system and evaluate it.

Seize this opportunity today to own a premium PURIFI 1ET400A based stereo amplifier built to the highest standard with high quality components to finally get the amazing sound that you have always dreamed about, for just a fraction of the cost.

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14 Days Money Back Guarantee!

“Put us to the test! Use the PURIFI 1ET400A for up to 14 days, risk-free. If for any reason you are not completely satisfied, simply return the product for a FULL refund. Just drop us a line at our support email to take advantage of our 14-Day Money-Back Guarantee. All we ask is that you send the amplifier back to us in the original packaging, and make sure that it is in the same condition. If you are not 100% satisfied with your purchase, you can return your amplifier for a full refund.”


Seize this opportunity today to own a premium Purifi 1ET400A  based amplifier built to the highest standard with only high quality components that will give you a magical musical experience that you have yet to experience on your loudspeakers.

Enjoy your leisure time listening to your favorite recordings, giving you a magnificent feeling of joy, with the Apollon Audio Purifi 1ET400A  – Purifi 1ET400A based amplifier being a major cause for the stunning performance of your loudspeakers.

And remember that you have 14 days to thoroughly test the Purifi 1ET400A amplifier in your own home, with your own loudspeakers in a familiar environment and get to know it and hear its performance. If by any chance the amplifier does not live up to your expectations just send us an email and return the amplifier for a full refund.


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