Owner’s Manual
Please read the Owner’s Manual completely BEFORE operating the unit.
Owner’s Manual
Please read the Owner’s Manual completely BEFORE operating the unit.
five
VTPH-1MM moving magnet version (use with cartridges above
1 millivolt output)
VTPH-1MC moving coil version (same as the MM version with an addi-
tional FET front end amplifier)
Design Considerations
• All-tube signal path (moving magnet version)
• Passive RIAA equalization for accurate phase and amplitude response
• Star grounding for low interference susceptibility and clean signal path
• Zero feedback—no feedback loops in the audio circuitry
• Low noise
• No switches in the signal path
• High input signal capacity without overload; see technical specifications
• Gold plated TIFF RCA and ground connectors
• Audio path capacitors are polypropylene and polystyrene
• Hand-picked components for accurate response
• Automatic muting at startup and shutdown
• 78,000 µF of power supply energy storage capacitance
• 4 levels of high voltage regulation
• Regulated soft-start DC filament supply
• Regulated tube bias supply
• Toroidal power transformer
• Rugged—0.10" thick aluminum chassis with 0.25" thick faceplate
• Reversing power line (AC) polarity switch for minimizing line-to-chassis
reactive currents and noise pickup
• Controlled warm-up of tube filaments and high voltage for extended
tube life
• Low plate operating currents for extended tube life and cool operation
• Front panel indicators for power, filament voltage, and output (mute release)
• Each unit is given a 48-hour burn-in, including rigorous bench and
listening tests
VTPH-1 Models
VTPH-1 Models
rigid voltage source to the tubes,
producing remarkable resolution of
musical events in time and sound
stage.
The circuit board layout was
engineered with all of its electrical
properties considered, in order to
achieve fine audio performance
with greater consistency than hand
wiring. Compromise was not an
option.
The unique design of the Herron
Phono Preamplifier, along with its
conservative design and operating
parameters, means that owners can
expect the industry’s highest level of
performance to be maintained over
the extended life of the unit.
Operating the Herron Phono
Preamplifier is easy and straightforward. The unit has been designed
to be exquisitely simple and user
friendly, with its operational readiness easily monitored.
During the manufacturing
process, every unit is subjected to
a battery of quality control checks.
Each unit is run through a full fortyeight hour burn-in, and then
measurements are made to make
sure that it is functioning correctly.
Last and most importantly, careful
listening tests are made in comparison to a reference unit, to make sure
each Phono Preamplifier performs
up to the strictest Herron Audio
standards.
The staff of Herron Audio are
audiophiles who regard the highquality reproduction of the
performance of music as one of the
finest pursuits in the engineering
arts. We at Herron Audio believe in
the pursuit of audio perfection. We
hope you enjoy the fruits of our
efforts. If you have any comments,
suggestions, or questions, please
contact us at 314-434-5416.
Herron Audio Vacuum Tube Phono Preamplifier
four