Musical Fidelity MX-HPA Instruction Manual

MX-HPA Fully Balanced Headphone Amplifier

The ultimate in balanced and single ended headphone listening.

The MX HPA is a very high performance fully balanced Class “A” headphone amplifier

in a beautifully designed and executed casework.

The unit features two inputs, balanced and single ended. These are separate and an
input select switch allows choice between separate balanced and single-ended sources.
These inputs accept normal line-level signals of 300mV nominal (suitable for 30mV­>3V) from a wide range of equipment.

Gain switching is provided to allow boost for higher impedance headphones, so the
unit is compatible with all dynamic headphones regardless of impedance. It is
recommended to use the LOW setting for headphones of 200 ohms or less; the HIGH
setting for headphones over 200 ohms or particularly insensitive headphones.

The front panel XLR/JACK sockets are dual purpose; it is possible to use either one or
two pairs of standard 6.25mm ¼” stereo Jack- terminated headphones; or a
of headphones, terminated in two three-pin male XLR plugs.
The necessary single ended/ balanced mode switching is carried out automatically on
connection of the headphone(s).

single

pair

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XLR Balanced input

and output lead

connections:

(for reference only, no

XLR signal leads

supplied)

Pin:

Functions: (line input/output)

Functions: (headphone outputs)

1

Ground (cable shielding)

Ground (not necessarily used)

2

Normal polarity ("hot" or “+”)

Transducer “+”

3

Inverted polarity ("cold" or “-“)

Transducer “-“

MX-HPA Fully Balanced Headphone Amplifier

FRONT VIEW

POWER GAIN HEADPHONE OUTPUTS
OFF/STDBY = ☼ HIGH (AS SINGLE ENDED STEREO JACKS) VOLUME
ON = ☼ LOW OUTPUT 1 OUTPUT 2 CONTROL

INPUT SELECT HEADPHONE OUTPUTS

BALANCED (AS BALANCED HEADPHONE XLRs)
RCA LEFT OUT RIGHT OUT

REAR VIEW

RIGHT INPUTS LEFT

XLR RCA XLR RCA IEC

BALANCED RIGHT BALANCED LEFT MAINS
INLET

XLR SOCKET PINOUTS

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