THÖRESS Parametric Phono Equalizer MKIII "Enhancer"

Dette produkt kan købes ved personlig henvendelse!

Bestillingsvare - Forventet leveringstid 4- 8 uger!

THÖRESS proudly presents the Parametric Phono Equalizer MKIII...

A highly versatile vacuum tube phono preamplifier which provides MM and MC gain
with excellent signal-to-noise performance in purely active operation mode (without
the aid of step-up transformer gain). And rather unique tone control facilities. More
specifically, the frequency response of the amplifier can be controled within wide
limits by varying the three edge frequencies
f1 (bass roll-off), f2 (bass turnover), f3 (treble roll-off)
of the phono de-emphasis characteristic independently of each other. By means of
three 6-position rotary switches TCSW1, TCSW2, TCSW3 (tone selectors). A topology
which obviously justifies the term PARAMETRIC PHONO EQUALIZER.

As a side effect of this unique design concept, the entire range of phono
equalization characteristics used by the prominent record labels throughout history
(including those of pre-microgoove 78-rpm era) can be activated or at least closely
approximated by choosing appropriate tone selector settings. The tone selectors
give rise to subtle bass, middeltone and treble control functions which are highly
effective tools for restoring tonal imperfections of the replayed vinyl programm
(eventually introduced during the recording or cutting process) without involving
additional clumsy and sound destructive tone control circuitry! Tone control is
particularly useful for the playback of monophonic records, nonetheless numerous
stereophonic records (including those from the 1970s and 80s or even current
productions) do benefit from subtle tone control facilities, as well. The favorable
range of the tone selectors has been determined and optimized by evaluating a
large variety of vinyl records with a laboratory sample. Thanks to it-s unique tone
control facilities the amplifier will allow you to listen more deeply into the groove of
records than it is ever possible with a phono preamplifiers restricted to a fixed
(RIAA) de-emphasis. Therefor we claim our preamplifier to be a PHONO ENHANCER!
A detailed description of the enhancement procedure can be found in the user manual.
Real-to-real tape NAB and IEC equalization (for various tape velocities) can be
installed on our preamplifier aside the phono settings, on request. So that the
device can be also employed as an ultimate stand-alone reel-to-reel tape playback
amplifier.

TOPOLOGY
The Phono Enhancer is entirely based on SINGLE-ENDED ZERO-FEEDBACK
schematics (using (2x12J5GT+2xPC86) or (2x6J5GT+2xPC86) vacuum tubes).
Decidedly ignoring the fact that many music lovers persistently believe in the myth
that balanced technology (and the associated cable configuration with XLR
connectors) is generally superior over single-ended concepts. Readers who want to
learn more about our view on balanced techniques and our general design approach
are encouraged to read the paper (THÖRESS - Behind the Curtain) available as
download on the ABOUT button of our website. With regard to our commitment to
single-ended design principles, the exclusive use of RCA jacks for signal input and
output was obligatory.

BUILT
The amplifier is built with meticulous hand construction using our proven point-topoint wiring techniques, whereas much care has been taken in arranging each
aspect of the internal construction to ensure low noise performance, ease of service
and the highest reliability for many years to come. The Phono Enhancer is an
ultimate component and as such a worthy complement to our Dual Function
Amplifier. The sonic presentation of the amplifier is of utmost refinement and thus
will easily measure up to the highest expectations of every discerning music lover or
professional user.
INPUTS
The amplifier comprises 6 phono inputs with gain pattern (5xMC+1xMM), five inputs
with 65dB MC gain and one input with 45dB MM gain (presenting a standard 47K
load to the cartridge). Alternatively, a gain pattern (1xMC+5xMM) can be
implemented on request. However, it is not possible to install an arbitrary MC+MM
gain pattern for technical reasons. The cartridge loading is
(100, 200, 300, 500, 1000 / 47.000) ohms and (500 ohm/47K, 47K, 47K, 47K, 47K).
on (5xMC+1xMC) and (1xMC+5xMM) standard units respectively. Other load values
can be easily installed on demand.

OUTPUTS
The output impedance of the Phono Enhancer is sufficiently low (around 300 ohms)
to simultaneously drive long cable runs and line inputs with an input impedance as
low as 10.000 ohms without compromising sound quality whereas the 3dB-down
frequency under 10.000 ohm loading donditions is still well below the audio band
(lower than 5Hz, 3.3MFD output coupling capacitor). The circuit terminates in triple
output (2x3 RCA jacks pairwise connected in parallel) which is useful for proper
(hum-free) dual-channel mono playback installation in the context of SINGLE-COIL
(mono) cartridges, as described in a dedicated paragraph of the user manual.
MAINS TRANSFORMER
The Phono Enhancer is equipped with a proprietary mains transformer produced inhouse to ensure the highest possible quality. This part has been specifically designed
for low body noise emission and low leakage. Nevertheless, it is mounted to the
chassis via isolation elements in order to eliminate even the slightest interference of
residual transformer vibrations with the circuit. Since the mains transformer is
produced in-house we can readily customize the amplifier for all kinds of mains
voltages, such as 100Vac (Japan), 120Vac (USA, Canada), 220Vac (South Korea,
China, Thailand, Indonesia), 240Vac (UK) or 245 Vac (Australia).

F E A T U R E O V E R V I E W
• Highly versatile vacuum tube phono preamplifier (phono equalizer).
• 6 phono inputs with gain pattern (5xMC+1xMM) and cartridge loading
(100, 200, 300, 500, 1000; 47.000) ohms. Alternatively, a gain pattern
(1xMC+5xMM) can be implemented on request.
• MC gain with state-of-the-art signal-to-noise-performance in purely active
operation mode (without the aid of step-up transformer gain).
• Minimalist single-ended zero-feedback schematic with passive de-emphasis
installation utilizing (2x12J5GT+2xPC86) vacuum tubes.
• Edge frequencies of the de-emphasis characteristic independently on-the-fly
adjustable within wide limits by means of three 6-position rotary selectors. Realto-reap tape NAB and IEC equalization settings can be installed aside the phono
settings on request.
• Entire range of phono equalization characteristics used by the prominent record
labels throughout history can be activated by choosing appropriate selector
settings. Equalization settings suitable for 78-rpm playback included. Highly
accurate RIAA equalization with tone selectors in default position.

• Subtle yet highly effective tone control facilities for restoring tonal imperfections
of the vinyl program, implemented without the aid of clumsy sound-degrading
conventional tone control circuitry.
• 3 outputs (3x2 RCA jacks) with very low output resistance.
• Full hand construction, point-to-point wiring throughout.
• Ultra low noise mains transformer produced in-house for 230Vac (115Vac via
jumper setting), 100Vac (Japan), 120Vac (USA, Canada), 220Vac (South Korea,
China, Thailand, Indonesia), 240Vac (UK) or 245 Vac (Australia).
• Non-magnetic aluminum casework, front and rear panel with anodized printing,
powder coated lids.
• Dimensions: 434x434x154 mm, 154=134+20 (case feet).
• Dimensions of the shipping box: 650x650x350 mm, weight 11.6Kg.