Review in STEREO magazine (Germany), January 2004
Preamplifier / Power Amplifier Accuphase C-2400 / P-7000

Champagne Revolution
by Holger Barske

The brand-new amps from Accuphase are visually presenting themselves once more in
the well-known champagne-coloured finish. From a technical point of view however it’s
the preamplifier conquering new grounds. And from a sonic point of view there isdefinitely a palace coup on the way.
There are actually two ways to discover the fascination inherent in the new Accuphasecombination of preamplifier C-2400 and power amplifier P-7000. The first and least
complicated way is to simply switch them on and enjoy the music.
The second and somewhat stony approach was inevitably leading to the question: "What thehell did the Japanese do here?" The answer thereupon is quite spectacular: Accuphase havereinvented the preamplifier, although not intentionally, I suppose. Most likely chased by theproblem that the market can no longer supply any true high-precision potentiometer (e.g. therenowned Penny & Giles pots are already history) a homemade solution has become
indispensable. What came out of this however can only be dubbed "radical": the C-2400 is
actually a volume control which, in passing by so to speak, is amplifying also.
The principles: right after the input selection a dedicated circuitry converts the input signal
voltage via 16 V-I converters into 16 "weighted" currents and then the single currents areadded again, or, in other words, clamped together. Each single current source can be activatedseparately and hence the amount of the overall output current is depending on which of thesingle currents had been switched on, thus determining the output level of this stage.
Eventually the current is converted into voltage again and, well, that's all that makes thispreamplifier.
All clear? Never mind as there is more detailed information available underwww.stereo.holgerbarske.com and Accuphase's own well-made brochure on the C-2400 also
provides a wealth of information in English about the AAVA principles.
In practise however the conversion of these -per se- simple thoughts and considerations
require quite some efforts and hence you'll find six boards tightly packed with components
populating the central "board-cage" inside the preamp. As usual, everything is neatly
separated from the power supply and shows a meticulous dual monaural layout nevertheless.
Like in fact all preamps from Accuphase, the C-2400 also comes with an abundance offeatures. To name but a few of those behind the sub panel: the comprehensive tone control
functions, which of course can be switched off, are accompanied by selector switches for thenew, optional phono equalizer module AD-2800. After all, one can now set the desired input

1impedance and gain directly from the front panel and does no longer need to detach themodule for this purpose.
The new power amplifier P-7000 is the successor to the P-1000 and although they look andfeel very similar, the P-7000 comes a little less expensive - very nice indeed. Like with allother amplifiers of this maker the built-in power meter has ever since been a kind of
trademark and therefore this amp's front panel is also graced by two gigantic analogue meters.
Those who don't like the "fidgeting" of the meter needles and illumination can simply switch
them off.
There is something else quite gigantic on the rear panel also, namely the speaker terminals.
They do not only seem to break the world record by their size, they also allow high manual
torque to ensure excellent contact for nearly any speaker cable.
Something new can be reported too as far as the amp's circuitry is concerned. It employs theso-called "MCS" architecture. MCS stands for Accuphase's original "Multiple Circuit
Summing-up" design and means that the input voltage amplifier is tripled in parallel
configuration, thus minimizing noise and distortions. Achieving a better noise reduction withsingle transistors is an old hat and we therefore consider the way Accuphase have gone adefinitely new approach.
The unit has been built with bi-polar solid-state devices throughout and the massive amplifier
sections with twenty-four transistors in parallel configuration per channel can supposedly
handle lots of current. After all Accuphase guarantee its stability into one Ohm, whereby theamp is delivering 1,000 Watt. No reason to doubt this in particular in view of the gigantictransformer and capacitance.
The issue "technical details" being over now we can blurt it out right away: this combination
is a sonic revelation! Yet it was really not easy to fully comprehend the combination's
character and eventually make it "countable". Because all that happened was greatly subject
to the sources respectively the programme material we played. Upon auditioning certain CDs
we tended to say "well, rather slender in the basses" but a minute later we had to completely
revise our impressions when playing other CDs. Save to say that it really does matter what's
spinning at the source.
The same can be said of the combination's capability of rendering a soundstage. When weauditioned a live recording of the singer/songwriter Towns van Zandt we enjoyed thewonderfully compact and fervent singing of the artist being concentrated in a virtually razorsharp centre of the performance around him. The next track on this disk was evidently
recorded at a different concert venue as we could hear the reverberant location. The "cosy"
atmosphere before had all of a sudden been transported onto the stage in a huge hall. This
really spectacular variability of rendering a soundstage can always be observed from being
very wide and flat as a board via a razor-sharp centre to music literally jumping out of thespeakers. All is possible.
And ever so gradually, after an extended consumption of music through these wonderful amps,
the tonal and dynamic sonic picture is perceived totally intuitive, i.e. one does not need tolisten consciously. On one side there is an abundance of power, impact and control wherebyon the other side there is the conscious renouncement of the last bit of "thrust". Astonishingly,
basses do not sound like being "carved from granite", they are well disciplined and rather
keep a low profile with respect to "brutality". The reason for this behaviour may in fact be2

found further up in the frequency spectrum and should be called "unobtrusiveness". Don't getme wrong however because the high-frequency resolution of this Accuphase-combination isabout the best money can buy. Yet there is that certain "velvety touch" which is capable ofwithdrawing any annoying high-tech flavour from the sound picture. Listening to music forhours and hours without stress? You bet, these amps can do it!
As already announced in STEREO 12/03, we had some adequate competitors ready forcomparison, namely the big Marantz-combination SC-7S1 and MA-9S1. The duel of preamps
did reveal slight differences in their sonic character: the brilliant smoothness and solidarity of
the C-2400 as opposed to the sparkling rendition of the beauty from Marantz. Although theSC-7S1 was able to display the performance similar to the C-2400 it was not quite on par withrespect to pinpoint focussing and order in the sound picture.
When comparing the two mono-blocks from Marantz with the P-7000 it became clearly
audible that the MA-9S1 has a powerful, round and emphatically emotional character. The
amp from Accuphase however played a tad more reserved if not laid back, yet tonally morestraightforward and always perfectly in tune. With respect to absolute power and drive bothamps seemed to be on par and capable of dominating almost any speaker system on thisplanet. Well, it's not very likely that someone is going to combine the preamplifier of one
maker with the power amp of the other - and that's all right. It was clearly audible that eachamp played at its best when combined with the partner from the own stable.
Soundstage at limits:
the C-2400 is capable of illuminating the musical event with incredible precision. Our
verdict: absolute world-class if not State-of-the-Art.
After this elaborate evaluation we do not hesitate to make the following statement: theAccuphase C-2400 is definitely the preamp discovery of the season. Eventually it cannot betopped by any other preamplifier known to us. In combination with the powerful P-7000 itwill enable you to "take off and fly away" when listening to music, something one canexperience not very often. Perfect harmony from the house of Accuphase. We drink to thisachievement and congratulate for the champagne revolution - Cheers!

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