Hifiman Prelude Fully Balanced Headphone Amplifier

Key Info Features fully discrete architecture with single-ended to balanced conversion. Employs a balanced amplifier design for increased noise rejection. Utilizes independent class A output for natural sound. Provides accurate channel balance for precise volume control. Offers single-piece aluminum housing for improved shielding. Uses customized toroidal transformer for clean power delivery. Offers multiple headphone connector options and versatile rear panel inputs/outputs. Includes protection circuit for headphone safety. Utilizes balanced configuration to cancel out noise for clean audio signal. Full Balanced Class A MOS-FET High Current Output The fully discrete architecture features a precise, single-ended balance conversion circuit that renders the single-ended RCA input balanced fully balanced. The input stage employs a fully balanced amplifier architecture, with precise, single-ended/balanced conversion. The pre-amplifier circuit is independent, adopting a class A output structure, with excellent power and natural timbre. The HiFi Man Prelude Class A Headphone Amplifier is the flagship amplifier in the range. The input stage uses a fully balanced architecture. As a result, even the single-ended RCA input is converted to a balanced signal to benefit from increased noise rejection. Also, the output stage is Class A giving a high powered output with a natural timbre. The unit has a very wide frequency response from 20Hz to 50 kHz and a THD of only 0.0009%. The power supply is designed to be low noise and uses a toroidal transformer that ahs a low magnetic field. ALPS Potentiometer The potentiometer ensures complete and accurate channel balance. A customized high-power, low-noise toroidal transformer, with multi-channel high-speed low-noise voltage regulator circuit, supplies power for the headphone amplifier. Fully balanced headphone protection circuit The housing is manufactured from a single piece of aluminum, which helps isolate harmful resonance that negatively affects sonic output. Low noise power supply and ALPS potentiometer The power supply of the HiFi Man Prelude Class A Headphone Amplifier uses a customised high power low noise toroidal transformer along with a high-speed regulator circuit. The unit also uses a high-end Alps potentiometer for volume control. Alps make the best potentiometers that have a long life and accurate channel balance. Finally, the housing is made from a single piece of aluminium for excellent shielding. Connectivity and headphone connectors There are many different types of headphone connector. The HiFi Man Prelude Class A Headphone Amplifier has outputs for the most common types. On the front of the unit there are two combo connectors that can take standard 6.3mm plugs or 3 pin XLR connectors. Next, here is a 4.4mm balanced connector. Additionally, the is a 4 pin balanced XLR connector that is specifically designed for balanced headphones. The front also houses the input and output selector switch and the volume control. Next, the rear of the unit has standard RCA and XLR inputs as well as XLR and RCA outputs for a preamp. What is a balanced amplifier? The elimination of noise is especially important with headphone amplifiers as the transducers are very close to your ears. As a result any noise will be much more apparent. Consequently, balanced amplifiers use a different lead configuration to normal RCA leads. For example two signal wires carry the same signal but in opposite phase. These are known as the hot and cold leads. When the signal is recombined at the amplifier any noise is cancelled out, similar to 2-2 being 0. Lastly, there are balanced connectors that are specifically designed for headphones these being the 4.4mm type and the 4 pin XLR type.