ALLEGRI REFERENCE PREAMPLIFIER

"This is quite something - my advice is Try it, Buy it, Keep it. The Allegri Reference is an audio masterpiece." 
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PASSIVE AUTOTRANSFORMER VOLUME CONTROL (AVC)

There are 129 individual 0.5dB steps, which give very fine volume adjustment at all listening levels. This incredibly wide range can accommodate very high source levels and very high sensitivity power amplifiers enabling refined volume control at very low levels, which is ideal for late-night listening. This is a 'first' for an AVC. In use, the control is seamless with no discernible steps. The Allegri Reference is the Holy Grail of audio preamplifiers.

The autotransformer configuration is employed for the Allegri Reference, as in the “stunning” Allegri+, because it has been shown to give by far the best sonic result when compared with conventional transformers (TVCs). The AVC also allows for a smaller core size, which has lower leakage inductance, which gives a far better transient performance and flatter frequency response. The AVC, is also much better than a resistive passive volume control, because of the very high input impedance and low output impedance.

The winding of each transformer comprises a single, unbroken, 260m (845 feet) length of 0.1mm (42SWG) Fractal™ wire, looped out 48 times around 48 pins, which are connected directly to the reed-relay pins. A short run of Fractal™ wire connects each of the signal in, signal out and ground, between the input/output connector board and each transformer relay board. Here is a clear case of less is MUCH more.
The laminations are 49 % Nickel, 51% iron mumetal, which gives the best bass performance and lowest overall distortion (less than 0.001%).

FRACTAL™ WIRE

This purely passive autotransformer design is wired throughout with Townshend Audio’s unique Fractal™ wire, which was developed over many years of critical listening, by the most discerning audiophiles and is audibly superior to plain copper, silver and even DCT copper wire. The result is the most accurate, uncoloured and open-sounding preamplifier possible, offering astonishing transparency and resolution of the finest details.

To realise the full potential of the Allegri Reference, it is most important to use Townshend Audio F1 Fractal™ interconnects for both input and output, as just one metre of inferior interconnect can noticeably degrade the sound.

FRONT PANEL CONTROLS

The left-hand front rotary control selects the inputs, 1 to 5. When the control is pressed, the menu options are activated. The right-hand control adjusts the volume. When the volume control is pressed, the sound is muted. A second press puts the unit in standby.

REMOTE CONTROL

With the remote control, you can operate volume change and mute, select any one of the five inputs and program a specific pre-set offset volume level. Display blanking is also switchable from the remote.

One press of the volume button, up or down, changes the volume by one step of 0.5 dB. If the button is held down, the volume steps will be spaced at half-second intervals at first and then the stepping amount will increase. This allows for large volume changes in a relatively short time, with the entire range from 1 to 129 in covered in 10 seconds. In use, it feels just right.

To equalise the often widely varying output levels of different source components, all inputs may be pre-programmed with your chosen volume level. The range is +/- 30 steps or +/– 15dB.

All inputs may be also be set at maximum volume fixed, or zero dB, for home cinema bypass. This feature allows the Allegri Reference to effectively "disappear" as it directly connects the AV receiver to the front left and front right power amplifiers. The volume is then controlled by the AV receiver. The mute function remains active. The mute function also doubles as a standby control.

The remote is an Apple-style remote control. It is very sensitive, so it is not necessary to point it directly at the unit. There is a convenient magnet attachment to store the remote under the front of the unit.

DISPLAY

The display is an easy-to-read seven-segment, white LED array, mounted behind a grey panel. LED displays are employed and are powered by interference-free DC. If a common LCD type screen were used, the sound could be compromised by the continuously running refresh clock.

The brightness of the display is controlled by an ambient light level sensor, so that the display is optimally readable when viewed in either bright light or total darkness. Display on/off is switchable by the remote control. The decimal point, on the input channel-display flashes with each input from the remote. This function is still active when the display is blanked. There is a further selectable option to have the screen blanked and then for the display to illuminate for five seconds, to five minutes, when a command is made from the remote control.

CLOCK DISABLE

It is well known that digital clock oscillators degrade the fidelity of the fragile audio signal, so the sound-blurring internal clock is disabled when listening. The clock is only activated when the remote control or the front panel controls are operated.

REED RELAY SWITCHING

The signal path is as simple as possible, with just four of the 102 ultra-reliable reed relays in the signal path at any one time. Reed relays are chosen for the tap switching as they are superior to all other switches. They have a life in excess of 30,000,000 operations, which is far longer than regular rotary switches, which tend to wear through the thin contact plating after a few thousand operations. Further, the relay contacts are in a vacuum, so there is no oxidation - and there is a slight rubbing action when the reeds close, which ensures perfect contact for audio. All internal connections are hard-wired with Fractal™ wire and there are no connectors in the signal path.

CONNECTIONS - BALANCED and UNBALANCED

The phono circuits are unbalanced for simplicity and the XLR connectors are wired in parallel with the phono connectors. The configuration is pseudo-balanced with pin 2 of the XLR signal and pin 3 ground. This avoids the use of an extra balancing transformer with all the associated complications and degradations in sound. The Allegri Reference has five stereo phono inputs and two pairs of balanced XLRs, in parallel with inputs 1 and 2. There is a 3.5mm jack socket, on the front panel, in parallel with input 5. For output, it has two sets of stereo phonos and one pair of balanced XLRs. The result is a preamplifier that can perfectly match any “Red Book standard” source component to any modern power amplifier.

DIGITAL CONTROL

All microprocessor programming is done in-house, by Townshend’s digital team.

SEISMIC ISOLATION

Seismic Isolation is fundamental to the design of the Allegri Reference. This gives isolation from vibration down to 3Hz in all three planes, which offers unmatched performance as a result. The four sturdy supporting feet contain fully-featured, highly compliant, air-damped Seismic Isolation modules. These block structure-borne vibration from the feet from reaching the autotransformers. This has a remarkable effect on the sound quality and is easily demonstrated by bypassing the suspension. When bypassed, the sound is exceptional by any normal standards, but when the suspension is incorporated the soundstage expands dramatically, with height, width and depth being greatly increased. With individual instruments, there is an easily discernible improvement in focus.

CONSTRAINED LAYER DAMPING

As a further part of the comprehensive vibration reduction, heavy mass-damped constrained-layer damping is employed in the structure of the chassis. This extra mass also greatly reduces the effect of external vibration, especially that introduced by interconnect cables.

FULL DEPTH CABINET

The Allegri Reference casing is full depth at 380mm (15”) front to back. This is most convenient, as it places the controls of the unit at the front of a typical hi-fi rack shelf whilst the connectors are conveniently accessible at the rear.

CABINET FINISHES

The case and isolating feet are made of anodised aluminium and are available in either a natural silver or black finish.

POWER SUPPLY

Although the signal path is totally passive in the Allegri Reference, the electronics and display require 12V DC. A universal power supply is supplied, with the appropriate plug, to suit your country's mains supply. Power and music signal are always separate. There is no direct connection between the power supply and the signal conductors or ground.

CONNECTING

To maintain the integrity of the Fractal™ wired transformers, it is strongly advised to use Fractal™ Interconnects for both the input and output cabling and to use Townshend Audio’s F1 Fractal™ speaker cable. This has been shown to give the best possible sound.

Frequency response at -10dB:	10Hz, -0.03dB, 20kHz, +0.1dB.
Maximum signal level:	4V RMS 8Hz; 10V RMS 20Hz and up.
Maximum DC offset :	5mV (For undistorted 8Hz).
Distortion:	2V, 1kHz, -113dB, 0.0002%. 10V, 1kHz, -96dB, 0.0014%. 2V, 20kHz, -96dB, 0.003%. 2V, 10Hz, -86dB, 0.005%. 2V, 20Hz, -115dB, 0.00014%. (2nd and 3rd harmonic only).
Intermodulation distortion:	19/20kHz, 2V. -86dB, 0.005%.
Channel separation:	20Hz-20kHz: Better than 110dB.
Impedance:	At 0dB, input impedance is 20kohm. At -10dB (normal listening) input impedance is 200kohm, for a power amplifier load with 20kohm input impedance.
Inputs:	Five pairs of RCA phono sockets (gold plated). Two pairs of XLRs in parallel with inputs 1 and 2. One 3.5mm stereo jack on front panel, in parallel with input 5.
Outputs:	Two pairs of RCA phono sockets (gold plated) One pair of XLRs.
Dimensions:	Width 234mm (5.3in), Height 100mm (4in), Depth 380mm (15in).
Weight:	9kg (20lb).
POWER SUPPLY
Input:	90-260V, AC 50-60Hz. Universal.
Output:	12V DC. 0,5W.