Reference Quality for Headphones
Meridian’s Prime Headphone Ampliﬁer is a reference-quality analogue headphone ampliﬁer that can replay audio from both analogue and USB-based sources. Built into an elegant and compact Allen Boothroyd-designed metal case, Meridian’s Prime Headphone Ampliﬁer also provides a preamp output to drive an external audio
system or analogue active loudspeakers.
The Prime Headphone Ampliﬁer is designed to appeal to audio enthusiasts who seek the highest possible performance from conventional analogue audio sources including personal stereo players, or from a computer via USB, listening on headphones, a conventional audio system or analogue active loudspeakers.
The Meridian Prime Headphone Ampliﬁer can be powered by the wall-mounted supply provided or, for even higher audio quality, by the Meridian Prime Power Supply. The use of this external power supply means that AC noise is kept well away from the pure analogue stages of the Headphone Ampliﬁer.
“Outside the Head” Analogue Spatial Processing
In addition to simply replaying stereo audio at the highest possible quality via headphones, Meridian Prime’s headphone outputs also include two “Analogue Spatial Processing” modes, i and ii, which replace the typical “in the head” experience of headphone listening with a smooth, natural feeling of spatiality that is much more like listening on a pair of loudspeakers in front of the listener.
Most recordings are made with loudspeaker listening in mind. When listening to stereo recordings on loudspeakers, your ears pick up signals from both channels. The sound from the right loudspeaker reaches your left ear a little later than it reaches your right (it’s further away) and vice versa. In addition, the high frequencies from the source that is a little further away are slightly attenuated.
The Prime Headphone Ampliﬁer’s Analogue Spatial Processing simulates these effects with pure analogue circuitry and a choice of two settings (plus bypass –useful if you are listening to binaural or coincident-pair recordings). The processing is carried out entirely in the analogue domain and is switched in and out from the front panel by logic-controlled analogue switches, ensuring that the audio signal path through the unit remains as short and pristine as possible.
In addition, relays are used to mute the outputs during switch on and off.
Throughout the Meridian Prime headphone Amplifier, the highest quality analogue audio components are employed to maximize audio quality.
A 6-layer circuit board provides ground-planes and maximizes signal isolation. The product is DC-coupled, for outstanding low frequency control and overall audio reproduction, and absolute phase is maintained throughout.
In addition to a pair of gold-plated phono connectors for line-level input, plus a 3.5mm mini-jack for connection of personal stereo players, the Meridian Prime Headphone Ampliﬁer includes a USB mini-B type connector for the replay of computer music sources.
The USB conversion system is powered from the interface, so that when it is disconnected, all digital circuitry in the unit is deactivated. The fully asynchronous USB2.0 interface supports signals at up to 192kHz/24-bit sampling and the USB input features a full complement of Meridian Resolution Enhancement technologies including an Apodising ﬁlter that improves the quality of digital signals, and upsampling of 44.1/48kHz sources to 88.2/96kHz prior to the built-in DAC.
Headphone & Preamp Outputs
On the output side, the Meridian Prime Headphone Ampliﬁer includes a pair of gold-plated line-level phonos on the rear panel that can be used to drive an external ampliﬁer or pair of analogue active loudspeakers.
Three front-panel headphone sockets are provided. One is a 3.5mm stereo socket for the connection of earbuds and similar devices, which presents an output impedance of 2Ω to suit these devices.
The other two sockets offer an exceptionally low impedance (around 3mΩ) and are standard ¼in stereo (tip-ring-sleeve) types, carrying both channels. They can be used either to connect two pairs of headphones or to attach a single pair of headphones wired with separate cords for left and right drivers, thus offering the opportunity to reduce headphone crosstalk.
Virtually all the active audio components are all at the rear of the unit, as close to the connectors as possible to minimize the audio path length, and are essentially remote-controlled from the front panel. This is even true of the high-quality analogue volume potentiometer, which controls the level of all the outputs. A special ﬂexible shaft coupling is employed to avoid microphony resulting from operation of the volume knob.
In addition to its use with headphones, the Prime Headphone Ampliﬁer is also an outstanding analogue preampliﬁer, allowing multiple inputs to be managed effectively and brought up to line level at extraordinarily high quality for driving external power ampliﬁers or powered analogue speakers.
A useful feature is the ability to turn off the preampliﬁer output when the unit is to be used solely for headphone listening.
This is achieved by holding down the power button. When in standby, the power indicator within the power button is blue; switched on with all outputs enabled it shows white; and when the preamp output is disabled it shows green.
Analogue signal path throughout.
6-layer PC board for maximum signal isolation and enhanced performance.
Analogue Spatial Processing offers dual-mode loudspeaker-like listening on headphones- with bypass.
Audio components mounted near rear-panel sockets for ultra-short signal path.
Analogue logic switching.
USB 2.0 asynchronous playback at up to 192Khz/24-bit featuring Meridian resolution-enhancement technology including low-jitter clocking, upsampling and Apodising.
Externally-powered USB input: disconnecting deactivates all digital electronics.
Dual ¼in stereo headphone sockets with separate-wire grounding (may be used with separately-wired headphones) plus 3.5mm stereo jack.
High-quality gold-plated sockets.
Headphone-only mode powers down preamp output.
Analogue volume control driven from front panel via ﬂexible coupling to minimize microphony.
Relay muting on power-up and power-down for thump-free operation.
Handmade in Meridian's state-of-the-art headquarters near Cambridge, UK.
New, elegant and durable metal enclosure design by Allen Boothroyd, double-skinned for lower noise, offers the distinctive Meridian look with no visible mounting screws.
1x pair Phono (stereo) (A1)
1x 3.5mm analogue stereo (A2)
1x pair phono (stereo) preamp out
2x ¼in A-type stereo phone jacks
1x 3.5mm stereo phone jack
|Overall Audio performance||
Output noise (input A1)
|Headphone compatibility||Suitable for impedances in the range
16–1kΩ or more. Suitable for open, closed,
in-, on- or over-ear models. Recommended
sensitivity >80dBspl/mW or >96dBspl/V
Volume with precise tracking, 70dB range
Power including rear output mute
|Processing||‘Out-of-head’ Analogue Spatial Processing
with dual settings plus bypass (headphone
Consumption <0.5W standby
<1W in quiescent
Silver metal ﬁnish similar to G Series
Width: 160mm (6.3in); Depth: 150mm (5.9in)
|Weight||0.9 kg ( 2.0 lbs)|