The Herron VTPH-2 phono preamplifier was created to address the retrieval of musical information from vinyl LPs without any compromise. The original design was only intended for use by a few dedicated music lovers in their cutting edge audio systems. The design was so good, and the demand so high, that the unit was refined and engineered to meet the requirements for a more durable unit manufactured in larger quantities. In the process, important refinements were developed and discoveries were made about tolerances and the threshold of human hearing limits.

Cartridge Loading Details
The moving-coil inputs can be loaded to a particular cartridge specification by externally connecting the appropriate resistors using the "MC LOAD" RCA connectors on the back of the unit, or they can be internally soldered at the MC INPUTS circuit board (this should only be done by a competent technician). The moving-coil inputs have no load resistors installed unless specified by the customer when the unit is ordered from Herron Audio. We recommend trying the VTPH-2 in the no-load configuration as the unit is supplied for most moving-coil cartridges. 47,000(47k)ohm RCA load plugs are supplied with the unit for optional use. Additional user specified loading plugs can also be purchased with the unit. The moving-magnet inputs are factory loaded at 47,000(47k)ohms, 100pF (standard loading for moving-magnet cartridges).

Herron VTPH-2 Features

Switchable moving-coil and moving-magnet operating modes with separate input connectors for each

Additional RCA connectors for external moving-coil loading

Cartridge biased moving-coil input stage allows for infinite load resistance (operation with MC cartridge totally unloaded)

Class A operation

Passive RIAA equalization for accurate phase and amplitude response

Reversing power line (AC) polarity switch for minimizing line-to-chassis reactive currents and noise pickup

Low plate operating currents and controlled warm-up for cool operation and extended tube life

Low noise

No mechanical switches in the signal path

Zero feedback, no feedback loops in the audio circuitry

Gold plated RCA and ground connectors

Audio path capacitors are high quality film type

Hand-picked components for accurate response

Automatic muting at startup, shutdown, and mode selection

Four levels of high voltage regulation

Regulated soft-start DC filament and high voltage supply

Regulated tube bias supply

Toroidal power transformer

Front panel indicators for power, voltage, and output (mute release)

Available in silver or black

Herron VTPH-2 Specifications

Tube complement: (2x12AX7, 3x12AT7) or (4x12AX7, 1x12AT7)

Gain MC Mode: (2x12AX7, 3x12AT7) 64dB or (4x12AX7, 1x12AT7) 69dB

Gain MM Mode: (2x12AX7, 3x12AT7) 43dB or (4x12AX7, 1x12AT7) 48dB

Frequency response: RIAA 20Hz to 20kHz ±0.1 dB

Signal-to-Noise Ratio: 80dB, A weighted

Output impedance: 500ohms nominal (12AT7 "V5" dependent)

Input impedance: infinite with no load resistors connected

Note: load resistors can be connected externally via RCA connectors or soldered internally

Absolute polarity: non-inverting (all modes)

Power requirements: standard IEC connector, most international voltages available

Overall dimensions: 17.6"Wx4"Hx10"D

Warranty: 3 years, parts and labor; tubes: 90 days

HiFi Review of Herron VTPH-2

The Herron VTPH-2 gives listeners all the benefits of a tube unit with few of the failings and a text-book technical performance to boot. It offers a level of vacuum-tube engineering (carefully combined with solid-state circuitry) that's rare at any price, unheard of at this one.