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HP-A4
24bit DAC Headphone Amplifier
![](https://www.fostexinternational.com/public/images/product_main/HP-A4_Top-main.jpg)
Main Features
- USB buss powered operation
- Linear PCM audio up to 24bit/192kHz and DSD audio up to 5.6MHz playback*
- Quick and easy hi-resolution playback in combination with "FOSTEX Audio Player" software
- HI/LO Gain selection (10dB) for wider range of headphones
HP-A4 24bit DAC Headphone Amplifier
![](http://fostexinternational.com/public/images/vari/High-Rez-Logo-300.jpg)
Model HP-A4 is a new, improved version of the acclaimed HP-A3. It offers up to DSD 5.6MHz and PCM 192kHz for superior audio playback functionality as well as the sophisticated and class-leading appearance of the flagship HP-A8C.
Fostex USB Audio Driver for Windows (V.2.2.1)
Dedicated USB driver software is necessary to install on PC for Windows. Please be sure to uninstall the old driver software, if any, before installing this new software.
You can download the Windows driver here
Windows and Mac OS Compatibility
We confirmed the compatibility with Windows XP*(SP2 or later) / Vista / 7 / 8 / 8.1 / 10 and Mac OSX(10.6 or later).
* Not compliant to XP 64bit.
In Detail
- USB buss powered operation without AC adapter
- Linear PCM audio up to 24bit/192kHz and DSD audio up to 5.6MHz playback*
- Quick and easy hi-resolution playback in combination with "FOSTEX Audio Player" software
- HI/LO Gain selection (10dB) for wider range of headphones
- Asynchronous transfer mode by using the custom made crystal
- Digital Filter selecting Roll-off characteristics and Cut-off characteristics according to the audio source
- Complies with USB Audio Class 2.0 on Windows XP (SP2 or later) / Vista / 7 / 8 and MacOS X 10.6 or later. **
- MicroSD (SDHC) card drive on the rear panel for future firmware update.***
* requires a DSD playback software on PC such as the upcoming "FOSTEX Audio Player". Both DoP and ASIO acceptable.
** requires the dedicated driver for Windows. Not compatible with Windows XP 64bit.
*** does not playback audio data stored on a microSD card
Specifications
InputUSB port sampling frequency up to 24bit/192kHz(PCM), 5.6MHz(DSD)
Interface USB high speed
Digital Connector: optical, square
Format S/PDIF (16bit/24bit: 44.1 – 192kHz)
Output
Phones Connector: Stereo phone
Max Output: 100mW (32-ohm loaded)
THD: less than 0.04% at 1kHz, 32-ohm loaded, 100mW
Frequency response: 20Hz - 80kHz +/-3dB (1kHz, 32ohm loaded, 100mW, FS 192kHz)
Analog Connector: RCA Pin
Reference output level 2Vrms
THD: less than 0.01% at 1kHz
Frequency response: 20Hz - 80kHz +-3dB (at FS 192kHz)
Digital Connector: Optical, square
Format S/PDIF (16bit/24bit: 44.1 - 192kHz)
General
MicroSD card slot: microSD card (SDHC)
Power: USB buss powered
Power Consumption: 2.5W
Accessories: 1 x USB cable (1.0m), 4 x rubber foot, manual
Dimensions: 113mm(W) x 34mm(H) x 155mm(D)
excluding protruded parts
Weight: approx. 500g
Document Downloads
The following documents are available to download in Adobe Acrobat format.
For more document downloads, check the manuals section in Technical Support