EIGENTAKT - Ultra Linear and Robust Class D Amplifier Technology

The EIGENTAKT Class D Amplifier Technology from PURIFI is the result of extensive research and patented IP aimed at addressing persistent challenges in Class D technology. This innovative technology delivers ultra-linear and extraordinarily robust performance that meets the needs of audio developers and end-users alike. It enables system integrators to design and manufacture products that are top-of-the-line in terms of audio performance, industrial-level reliability, and cost-effectiveness.

Unlike traditional Class D technology, EIGENTAKT eliminates common stigmas such as "harsh sound" and "frail reliability". This has been confirmed by objective measurements, subjective listening tests, and harsh robustness testing.

EIGENTAKT is available in multiple forms ranging from a line of drop-in Amplifier Modules to Amplifier Designs for Licensing by OEM's.  At PURIFI, we are open to discussing custom or semi-custom EIGENTAKT Designs based on our IP.

Unrivalled Performance

  • Best-in-class linearity specifications translate into crisp and clear music reproduction across all levels, frequencies and loads.
  • No inherent "sonic fingerprint" - just complete transparency.
  • Enables development of top tier end-products with little development effort. 

Robust & Reliable

  • Purposely designed and tested with extreme ruggedness and quality as main objectives.
  • End result is a negligible low amount of field returns or quality claims.
  • Saves cost, increases end-product profitability and enhances brand value for OEM's.
  • Improves user experience.

Integrates Easily

  • Compact footprint (size) with well-defined interface.
  • Resilient against power-supply variation/quality.
  • Optimized for low EMC and adopts at the application level without integration headaches.
  • Significantly shortens and reduces end-product development time and cost.

EIGENTAKT - Amplifier Modules

Do you want your audio products to have sublime sonic performance? Then, incorporating PURIFI's EIGENTAKT Modules will be a very attractive choice... 

EIGENTAKT modules are compact, easy to integrate, super robust, and cost-effective. And yes, of course, with  unsurpassed linearity specification resulting in best-in-class audio performance which will set your end-product apart from the competition.

To make evaluation simple, we offer 'EVAL' kits that in addition to the EIGENTAKT module(s) include a neutral, high-performance audio front-end. You can easily connect the EVAL kit to a power supply and conduct your own measurements and listening tests. The EVAL kits are also perfect for DIY enthusiasts who want to create a high-end audio amplifier that outperforms commercially available amplifiers, but at a fraction of the cost.

For a more information, including detailed datasheets and users guides, please visit our webshop.

Product Catalog & Data Sheets

Amplifier Modules & Evaluation Kits

General Products & Evaluation Kits

Mono/Stereo Evaluation kits consist of a front-end board + 1ET400A amplifier module(s).
The front-end board contains a pre-gain stage, low-voltage regulators, balanced analog input (XLR), speaker terminals and connectors for PSU/control. (PSU must be sourced separately) 


OEM Amplifier Products

In addition to our Catalog modules (presently, 1ET400A and 1ET7040SA), PURIFI also develops custom or semi-custom products based on EIGENTAKT IP. Please contact us directly to explorer this option.


What Makes EIGENTAKT So Special?

Firstly, we recommend that you experience EIGENTAKT with your ears by listening to your favorite music. No data sheet can fully convey the clarity, detail and enjoyment that EIGENTAKT offers during a listening session.

However, objective data sets are also essential to explore and compare when auditioning amplifier technologies. Hence, we strive to create detailed, accurate, and reliable data sheets with an abundance of relevant information. Please feel free to contact us directly if you find any missing information.

EIGENTAKT incorporates a comprehensive protection system that makes it tremendously robust and easy to integrate. Please refer to data sheet for details. 

Here's some important characteristics worth noticing: 

Negligible THD & IMD

The patented EIGENTAKT ErrorCorrection IP ensures ultra-high loop gain (>75dB) in the entire audio band. This figure corresponds to an unprecedented 110MHz Gain-Bandwidth Product and produces consistent ultra-high performance across the audio spectrum unmatched by audio amplifiers of any technology or operating class.

Intermodulation Distortion (IMD) is a very good measure for how well an amplifier handles complex signals. Sonically low IMD means a highly resolved and stable stereo image across the whole spectrum, even during very complex and busy passages.

THD remains extremely low at any frequency and any power level right until clipping. This translates into a total lack of sonic signature, and an ability to reproduce any type of music without preference for genres or production style.

Negligible audible noise. Deep black silences and a generous and detailed sound even at very low playback volumes.

Load-invariant Frequency Response & Negligible Output Impedance

EIGENTAKT handles difficult loudspeakers with ease, including those that challenge most other amplifiers. The Frequency Response (FR) is very flat in the entire audio-band with a sensible 60kHz bandwidth. Variation between high-impedance and low-impedance loads is completely negligible as indicated by perfectly overlapping 2-ohm to "open-load" FR plots. 

Minimized sensitivity to out-of-band noise from DACs reduces requirements on the DAC reconstruction filter and enables possibility of a shorter signal path between DAC and loudspeaker (integrated products). The reduced sensitivity also ensures problem-free operation with outboard DACs over which you may have no control.

Output Impedance in the sub milli-ohm range resulting in a five-digit Damping Factor. 

Very low Idle Losses & Reduced Electromagnetic Interference (EMI)

EIGENTAKT ErrorCorrection allows relaxed timing of the power MOSFETs without degrading audio performance. This brings additional benefits in terms of very low Idle Losses and low Electromagnetic Interference (EMI).

The minimized Idle Losses combined with high Power Efficiency allows the EIGENTAKT technology to run cool even within constraint enclosure sizes and minimal heat sinking. EIGENTAKT is specified for continuous output power with a realistically implemented thermal system. 

Low Electromagnetic Interference (EMI) makes it convenient and easy to integrate EIGENTAKT modules at the system level. Typically, regulatory tests are passed with little to no effort needed.