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    PURIFI 1ET400A 1x425W Eigentakt Amplifier Module

    € 272,69€ 329,95 >10 In stock: delivery time 1-4 business days
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    Product description

    The 1ET400A is a single-channel, ultra-high performance, analog-input Class D amplifier module capable of over 400W of power and provides an audio quality level that sets the standard for power amplifiers of any operating class.



    • Single-channel, analog input
    • Negligible THD and IMD
    • Extraordinary low noise
    • Load-invariant response
    • Exceptionally clean clipping
    • Low losses & high efficiency
    • Small formfactor 


    Product details

    PURIFI 1ET400A | Eigentakt | Amplifier Module


    This high-performance amplifier module is based on the Eigentakt technology from PURIFI. The 1ET400A is one of the most high-end options from our amplifier module category. Eigentakt is the implementation of PURIFI's continuing research into nonlinear control theory that produced the first mathematically exact largesignal model of self-oscillating amplifier controllers. This breakthrough allows complete optimization of the feedback circuit and improves performance by at least an order of magnitude over existing implementations. The Eigentakt technology allows for extreme low THD at any frequency and power level. The negligible IMD (intermodulation distortion) creates a highly resolved and stable stereo image. Thanks to the very low output noise, this exceptional performance is preserved even at low listening levels.


    The 1ET400A also features a comprehensive protection system that makes it robust and easy to integrate. 



    • High loop gain (>75dB) in the entire audio band
    • Negligible Intermodulation Distortion (IMD)
    • THD remains extremely low at any frequency and any power level
    • Negligible output noise
    • High power supply rejection ratio (PSRR)
    • Controlled, second-order low-pass response


    What’s In The Box?

    • 1ET400A amplifier module 


    The 1ET400A module requires attention on the power supply and signal input connections. We recommend to use a dedicated front-end module that provides a buffered input and handles the power supply connections. PURIFI developed the FE02 stereo front-end module for this purpose. This module enables an evaluation setup but is also suitable for DIY applications. The FE02 front-end module is supplied with the PURIFI EVAL1 kit available on this page.


    Article number
    Rated power output

    425 watts at 4 ohms
    227 watts at 8 ohms
    450 watts at 2 ohms

    Minimum load
    2 ohms
    > 94%
    Signal-to-noise ratio (SNR)
    131 dB
    0.00017 % THD+N at 20-20,000 Hz, 4 ohms, 100 watts
    Frequency response
    0 - 60,000 Hz
    12.8 dB
    Input sensitivity
    Input impedance

    4.4k ohms (differential mode)
    2.2k ohms (common mode)

    Amplifier Classification
    Class D
    Circuit Topology
    Speaker output channels
    Input connection type
    Pin header
    Speaker output connection type
    Pin header
    DSP function
    EQ Adjustment
    Power Requirements
    25 - 70 VDC (symmetric supply +/-)
    Power inlet connector
    Pin header
    Current limit
    25 A
    Under/over voltage protection
    Dimensions (L x W x H)
    82 x 63 x 35 mm
    Mounting hole spacing
    75 x 56 mm
    Mounting hole diameter


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    1ET400A 1x425W Eigentakt Amplifier Module
    € 272,69
    € 329,95
    1ET400A 1x425W Eigentakt Amplifier Module
    >10 In stock: delivery time 1-4 business days
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