VTPH-2A Vacuum Tube Phono Preamplifier

VTPH-2 Front Panel  

titaniun gray face

silver and black face plates also available

all face plates are 1/2 inch thick brushed anodized aluminum

 

Silver             Gray             Black


VTPH-2 Back Panel

back panel - click on image for larger view

 

LIVE, in-your-room clarity

Totally unique tube circuitry configuration:

high end performance with very low distortion

exceptionally low noise using tubes

extended tube life

Immediately You Know!

None of that harshness, dryness, or hardness that most solid state phono stages produce.


"Pick up an acoustic instrument and the better it is, the greater the sense of life, of energy just waiting to burst forth. This is exactly the quality that the Herron phono-stage captures. All that texture it brings to instruments is built on micro-dynamic definition and the ability to capture the harmonic envelope, the pattern of energy that extends from instruments."

"The colour and ability to reveal each step in the growing intensity of a crescendo mark out the beautiful balance that the VTPH-2 strikes between the instrumental detail that gives music its beauty and the body and presence that gives it its drama and so much of its passion."

"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."
- Roy Gregory hifi+ issue 58


Customer Review 2018
Herron VTPH-2A Phono Stage

"...I played the albums I knew very well. During each jump in price I made with the previous stages, I found they offered more. Some more detail, others better bass or staging. You get the idea. The Herron hits on all of them. It leaves nothing out. Each aspect of what you want in a sound stage the Herron delivers in spades. As I went through each album, I swore the other stages had opened them up and allowed me to hear all the album had to offer. I did not think there could be anything else hidden, no new instruments or nuances going on that I never heard before. I honestly didnít think the Herron could improve in that area, I did expect other things from it, but again not in this area since I already had heard several layers into my music thanks to the other stages. Boy was I dead wrong on this. In fact it may be the biggest thing that continues to catch me off guard and gets that smile going from ear to ear."...

..."I sold a collectible from my other hobby to help purchase this Herron VTPH 2A and I was worried I would have regret. I have ZERO regret and can now absolutely, positively cross off the phono stage as my upgrading days for that piece of gear are done. I have no interest in hearing anything else. Thank you Mr. Keith Herron for making one incredible piece of musical equipment. It is worth every bit of the asking price if you are into vinyl." - By Michael Catucci ē Posted: June, 2018 See Complete Review


More Customer Reviews 2018
Herron VTPH-2A Phono Stage

First impression: Herron VTPH-2A phono preamp - By professorsvsu: 07-16-2018 6:15pm;   "I got my VTPH-2A this morning and it's up and running. After about five hours of spinning vinyl, I'm pretty sure I've wet myself, MULTIPLE TIMES! I've primarily played vinyl that I've had for decades, music that I thought I was intimately familiar with. I was wrong. There's nuance I never knew existed. Everything about the VTPH-2A is "right". The bass is tight, vocals superb, instruments have places, etc. All that I've listened to sounds new and fresh and the most masterfully recorded vinyl sounds live. What I've read about on this forum concerning the VTPH-2A (pretty much all stellar) is true. I've had five different phono preamps and nothing can compete with this, NOTHING. It's a bad ass and definitely a keeper."

"Brilliant!" - By Dorian Workman: "Magnificent! So much better than the Parasound JC3+ and Sutherland Duo that I also tried. This one is a keeper!"

"Bravo! - By Darko: "Beautiful sound. Bravo Herron!"

"Excellent State of the Art Phonostage" - By Doug: "I have had the Herron for about a month. It takes time to break in. It adds impressive presence to music of all kinds without loosing detail. Very smooth over the entire audio spectrum. It is very easy to set up. I have two turntables connected to it, both VPI Prime Signatures with Van den Hul Crimson and Stradivarius (through Bob's Devices SUT to MM input) carts. In turn the Herron is connected to a Pass Labs INT-250 and in turn to B and W 802 D3 speakers. So if the Herron were anything but stellar this system would show it immediately. Happy to say that the Herron is easily up to the task of enhancing a high end system. It just keeps getting better each day. I like Keith Herron's philosophy of simple yet elegant electronics and customer support. Its made in the USA. Why pay twice as much for a foreign product and get poor customer support."

"Spectacular Tube Phono Preamp!!!" - By Tom G: "Exceptional sound and greatly improved dynamics are the benefits that I found when I upgraded from the Pass Labs XP15 phono preamp to the Herron Audio VTPH-2A. I liked the Pass unit quite a bit, but some music sounded a tad harsh, so the folks at NeedleDoctor recommended the Herron phono preamp and I could not be happier. This Herron unit is almost as quiet as the solid state Pass but offers greater imaging, depth and tone." "The rest of my system includes: Rega RP 10 turntable with Rega Aphelion MC cartridge, SimAudio Moon Evolution P7 preamplifier, SimAudio Moon Evolution W7 power amplifier, Benchmark DAC2 DX digital to analog converter, McIntosh MR88 AM FM HD tuner, Sonus Faber Cremona M tower speakers, REL R328 subwoofer, Audioquest Columbia interconnects, Audioquest Mont Blanc speaker cables, Furman IT Reference power conditioner"

The Herron VTPH-2A 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 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.


VTPH-2 loading resistors
external MC load resistor RCA plugs

Separate moving coil and moving magnet inputs

The Moving Coil "MC" Inputs:

The moving coil inputs have an additional 22 dB of gain which is provided by a proprietary FET very low noise linear gain stage connected directly to the MC inputs. The moving coil FET gain section is connected in front of the tube section when the unit is in the MC mode. This moving coil FET gain section has been designed specifically to avoid the sonic artifacts found in many solid state designs.

Moving coil loading RCA resistor plugs can be inserted into the back of the VTPH-2A at the "MC Load" connectors to properly load specific moving coil cartridges. Check with your cartridge manufacturer for recommended loading.

The Moving Magnet "MM" Inputs:

The moving magnet inputs send the cartridge signal directly to the tube section and bypasses the MC FET gain stage. The moving magnet inputs provide all tube amplification of the signal from the cartridge. The moving magnet inputs have an internal 47k Ohm loading resistor for each channel and 100pF "Miller Effect" loading capacitance which is provided by the grid of the first 12AX7 tube.

Cartridge Loading:

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).

Why loading plugs instead of dip switches?

Reason #1:

When using DIP switches the sound quality will degrade with time and potentially become grainy and bright as unwanted harmonics are added due to contact nonlinearity.

Mechanical switch contact resistance (which is nonlinear with voltage) can be in the order of magnitude of the loading resistor itself particularly at the very low voltages which are generated by a moving coil cartridge. The music information can be down in the range of nanovolts. This problem will be exacerbated with time as the DIP switch contacts which are open and not sealed are exposed to air will develop oxidation and layers of contamination from environmental humidity and air pollution.

Note A: The VTPH-2A uses electronic switching for audio signals when changing from moving coil to moving magnet mode. This is initiated by one mechanical switch which does not carry any analog audio signals.

Reason #2:

So we spent how much on that cartridge and turntable and we load the cartridge with DIP switch contacts and only the resistors that are connected to it?

External loading plugs allow the user to hand pick the resistor brand and type if he or she is so inclined. Yes, resistor brands and types do sound very different. In a way this is comparable to tube rolling.

Reason #3:

The "infinite loading" option.

The VTPH-2A will not load the cartridge at all if no loading resistors are plugged into the MC loading inputs. This is because the moving coil input stage of the VTPH-2 utilizes the electric field generated by the cartridge to amplify the voltage and no current is drawn from the cartridge (there is no load on the cartridge). This can give an extended sense of dynamic freedom and sound stage as it reduces the work done by the cartridge and cartridge/groove interaction.

Note B: Some cartridges will need loading in order to reduce their inherent rise in high frequency response.

Reason #4.

You don't have to get inside the unit to change the loading, you can do it while you are listening in order to get a immediate and real sense of how the loading changes the sound.

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-2A Vacuum Tube Phono Preamplifier Features

Specifications
Tube complement (2 x 12AX7, 3 x 12AT7) - most popular, or
(4 x 12AX7, 1 x 12AT7)
Gain MC Mode (2 X 12AX7, 3 X 12AT7) 64 dB
(4 X 12AX7, 1 X 12AT7) 69 dB
Gain MM Mode (2 X 12AX7, 3 X 12AT7) 43 dB
(4 X 12AX7, 1 X 12AT7) 48 dB
Frequency response RIAA 20 Hz to 20 kHz ±0.1 dB at 10k Ohm output load impedance and higher
Distortion Less than 0.03% at 2.45 volts output at 1kHz at 20k Ohm and higher output load impedance (tube selection dependent)
Note: Lowest distortion and best performance occurs with output loading at or above 20k Ohms - this gives the most dynamic sound
Signal-to-Noise Ratio 88 dB, A weighted
Output impedance (2 X 12AX7, 3 X 12AT7) 400 ohms
(4 X 12AX7, 1 X 12AT7) 500 ohms
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" wide x 4" high (including rubber feet) x 10.25" deep
Warranty 3 years, parts and labor; tubes: 90 days
U.S. Retail Price $3,650 U.S.D.

NOTE: The VTPH-2A is an improved version of the VTPH-1 single input version which was reviewed by Stereophile in March of 2000

Stereophile: March 2000, Vol.23 NO.3 Herron Audio VTPH-1 Phono Stage

"It's competitive with anything I have rated 'Class A.'"
- Michael Fremer

"It was a pleasure to measure such a well-engineered phono stage."
- John Atkinson read the review


Ultimate Audio, March/April 1998
Herron Audio VTPH-1 Phono Stage

"The Herron Audio phono preamplifier produced something I've never heard from an audio system before: live, I mean LIVE, in-your-room clarity. The clarity and the absolute transparency this phono section delivers takes the listener not into the world of reproduction, but production. Great recordings assume their full, explosive, lifelike dynamics, with bass that is tight, deep and articulate complete with shading and definition; lightning-fast transients; exceptional control of the leading and trailing edge of the musical wave form. Tonally and harmonically, the Herron transports you to a place you have never been before."

"If you want the best (that I've heard) in line stage and phono stage reproduction, from the deepest, the tightest, cleanest bass your system can reproduce to the silkiest, most open highs you can hear, listen to what's happening at Herron Audio. You'll be glad you did."
- Richard Foster read the review


Copyright © 1996 - 2018 Herron Audio. All rights reserved.
Herron Audio, div. of Herron Engineering, Inc.
12685 Dorsett Road #138, Maryland Heights, MO 63043 U.S.A.
phone: 314-434-5416