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INTRODUCING THE H-3000V PHONO STAGE

The H-3000V is a special version of Allnic Audio's top of

the line phono stage model. Like all Allnic Audio

products, it uses Permalloy (iron and nickel alloy) for its

transformer cores. Allnic is grateful to Mr. G.W. Elmen

of Western Electric for inventing Permalloy for

transformer core use, and in so doing, providing an

enormous service to recorded music listeners

everywhere.

The H-3000V has the following features:



LATEST UPGRADED OUTPUT TRANSFORMERS:

The H-3000V is equipped with the latest

production, larger output transformers (available

on all H-3000s produced after September 1, 2010

and otherwise available as an upgrade for the H-

3000 from Hammertone Audio).



LCR TYPE PRE-RIAA AND RIAA EQUALIZATION:

RIAA equalization is a specification for the correct

playback of vinyl records, established by the

Recording Industry Association of America. The

purpose of the equalization is to permit longer

playback times and improve sound quality. Before

the establishment of the RIAA equalization

standard, different production companies utilized

different equalization curves.

Vinyl record production equalization is a form of

establishing a flat frequency response for the

playback of recorded music. The necessity for this

equalization process arises from mechanical

difficulties inherent in record production. In order

to prevent the cutting needle from over-cutting into

the next record groove in the bass, as a record is

cut, some bass frequencies are attenuated. In the

treble region, in order for high frequency sounds

not to be masked by the noise inherent in moving a

stylus over and through a modulated vinyl surface,

some treble frequencies are boosted. With the

application of the correct filtering techniques on

playback, the result is a flat frequency response

with better signal to noise ratios.

The H-3000V is equipped with newly developed

Allnic "Multi-Curve" LCR units (one for each channel)

which have four (4) Turn-overs (frequency options)

and four (4) Roll-offs (gain reductions in dB). These

new units provide for the reproduction of various

recording curves (both for bass attenuation and

treble boost) used by different companies prior to the

establishment of the RIAA standard. There are 4 Turn-

over options, at: 250Hz, 400Hz, 500Hz RIAA and 700Hz.

There are 4 Roll-off options (at 10KHz): -5dB, -11dB, -

13.7dB RIAA and -16dB (See Figure 7).

There are four de-emphasis methods for equalization to

that can be applied at playback:

Active filters (Negative feedback types):

Different quantities of negative feedback are applied,

with deeper feedback to the high frequencies and

shallower to the low frequencies. The benefits of this

method are improved signal to noise ratios, low cost and

consistent operation. Some of the shortfalls are looser

bass reproduction and, possibly, a pinched and

compressed high frequency playback due to excess

feedback ratios.

Passive filters (CR type):

The frequencies are filtered to fit the RIAA specification by

varying the amount of attenuation at different frequencies

through a complex capacitor-resistor network. This

technique results in no voltage overload, purer

reproduction (because there is no feedback), and more

accurate RIAA compensation. However, there are problems

because the system provides no gain, and insertion loss and

impedance matching issues arise.

Hybrid filters (use of both CR and negative feedback

types):

In this method, both types of filters applied separately; an

active filter is applied to the low frequencies and a passive

filter to the high frequencies. Unfortunately, both the

advantages and disadvantages of each of these two types