from $399.99
The Fostex HP-A4 is a compact 24-bit USB DAC and headphone amplifier designed to elevate your audio experience. It supports high-resolution audio playback with sample rates up to 192 kHz for PCM and 5.6 MHz for DSD, ensuring faithful reproduction of your digital music. With a frequency response of 20 Hz to 80 kHz and low total harmonic distortion, this amplifier delivers clear and detailed sound to your headphones or stereo system, all powered conveniently via USB.
Match your amplifier's power output (Watts RMS) to your speakers' sensitivity and impedance (Ohms). Do not obsess over astronomical peak wattage claims; RMS is the true measure of sustained power. Available from $399.99.
Amplifiers have practically zero ongoing costs aside from electricity, which is highly variable based on usage volume and class type (Class A uses more power than Class D). Good amplifiers can last decades with proper care. Consumables are virtually non-existent unless using tube amps.
Common Failure Modes
Solid-state amplifiers are extremely reliable. Failures usually stem from blown capacitors, overheated output transistors, or physical wear on volume potentiometers. Proper ventilation prevents 90% of heat-related failures.
Match your amplifier's power output (Watts RMS) to your speakers' sensitivity and impedance (Ohms). Do not obsess over astronomical peak wattage claims; RMS is the true measure of sustained power. Class D amplifiers run cool and are compact, while Class A/B offer traditional warm sound at the expense of heat and size.
Solid-state amplifiers can last 20+ years. Capacitors may eventually dry out and need replacement.
The Fostex HP-A4 24-Bit USB DAC Headphone Amplifier is available at bhphoto, starting at $399.99.
Amplifiers have practically zero ongoing costs aside from electricity, which is highly variable based on usage volume and class type (Class A uses more power than Class D). Good amplifiers can last decades with proper care. Consumables are virtually non-existent unless using tube amps.
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