Review in STEREO magazine (Germany), Issue 10/2007
Preamplifier Accuphase C-2410

Shadow-Boxing ?
by Matthias Böde

Accuphase has gone over the - in our opinion "superman-preamplifier" C-2400 and launched it again as C-2410. We were of course more than inclined
to compare the new one with its predecessor, but we were also wondering if
this might eventually become a dead-end race - or is the newcomer indeed thebetter preamplifier?
In view of the C-2400's price tag it would seem a bit strange to talk about areasonable offer here, but the preamplifier from the noble maker Accuphase in Japanis exactly this: in the usual way meticulously crafted, luxuriously equipped,
technologically innovative and built for eternity. Apart from this it could establish itself
amongst the best and partly much more expensive preamplifiers on this earth when
we tested it for issue 01/2004.
A great deal of this success can certainly be attributed to the complex "AAVA"
circuitry (see inset for further details) which by an ingenious manner from input tooutput is providing the signal path with a precise, stable and strictly channelseparated volume control. The C-2400 was the first component of the company fromYokohama to offer this new technology and its upgrade has mainly been dealing withthis section.
If, like in STEREO's listening room, both generations are put next to eachother, there are a few cosmetic changes attracting the eyes at first. The former roundbuttons for some secondary functions have been replaced by square ones. The sidecheeks, previously in straightforward grey, are now clad with noble ebony panels andthus give the preamp a particular appearance. Lastly, the lettering beneath the red
LEDs of the display is now illuminated.
What remained however is the wide flap which upon pressing a tiny button(labelled "Open") on its right is gently moving down in order to access the lesser usedbuttons and controls. They make the C-2410 the most versatile high-end preamplifier on the market; a "wonder of features", indeed. When the flap is closed again theC-2410 looks like any other purist's preamp.
Instead of the two-tape record selector switch of the C-2400 the successor
features only one recording terminal but is equipped with a three-step selector for
overall gain of 12, 18 or even 24 dB. For the C-2400 this selector was hidden at therear panel and we always thought it would certainly deserve more attention. Althoughfactory-set to 18 dB we do recommend the lower value, i.e. 12 dB. It's because withthis setting the preamplifier does indeed sound more airy, swinging and eventuallymore natural. Going higher in gain will gradually result in a tad more dense sonicpicture while the airiness gives way to a slightly fatter timbre.

And there is actually no reason for a basic gain higher than 12 dB, because
nearly all CD players come with an output voltage so high that even when listening tomusic at high levels the volume control itself could hardly be set beyond the 12o'clock position. Still, this feature does make sense, for example when - Accuphase
may forgive us - Apple's rather "quiet" i-Pod or something similar is to be connected,
which in comparison with a good CD player would usually sound thinner andbleached in sonic colours. A higher gain setting of the C-2410 would remedy this inso far that the flat sound is becoming more vigorous and vivid. The same applies torun-of-the-mill DVB-tuners and other rather standard appliances for music
reproduction.

Success through "AAVA"
The "Accuphase Analog Vari-gain Amplifier" is the heart of the C-2410.
After having always employed potentiometers of the highest calibre to take care of
the volume control, with the advent of the C-2400 Accuphase introduced a unique
circuitry which was to combine the functions of amplification and volume control in
one unit: AAVA. The volume knob on the right is actually linked to a CPU which
detects the position of the volume knob and operates, respectively combines
altogether 16 current on/off switches according to the position of the knob, whereby
the sum is resulting in the overall volume. The input signal is converted into 16
weighted current stages which in combination are to yield more than 65,500 stages.
This procedure is eventually perceived by the ear like a continuously gliding
analogue potentiometer. Accuphase claims some distinct advantages achieved bythis proprietary AAVA circuitry, such as stable frequency response regardless ofvolume setting, outstanding signal-to-noise ratio and distortions reduced to an
absolute minimum, lowest left/right channel crosstalk and, last but not least,
absolutely no mechanical wear. Muting and balance control are likewise governed by
AAVA and thus eliminating any impedance and capacity problems inherent inconventional solutions.

Like any other preamp the C-2410, too, needs a certain play-in time before
one can take it really serious. So please follow our advise and have it continuously
switched on for the first two weeks or so. It goes without saying that the phase of themains supply needs to be checked and matched, because otherwise you would
never experience how far this dream amplifier can go sonically.
This would be a real pity because the C-2410 could indeed put the screws on
the top references in our list, which some time ago managed to edge out its
predecessor from the highest position, though only by a small margin. But for thetime being the family get-together of the two generations was on the agenda and it
goes without saying that the same basic gain has been selected for comparison.
Without degrading its ancestor, the C-2410 could indeed shine with somesonic advantages: its charming sound picture, although hardly more natural, excelled
in being more cleaned up, so to speak, and inherently more stable. I'm sorry if thismay sound like mere shadow-boxing, but we find ourselves at a level where even themost minute detail can be important. The new C-2410 is able to remove one or theother light veil that was still hanging around in the sonic picture of the C-2400.
Consequently, this means the C-2410 is able to yield a higher level of realism and tomake all technological aspects moving further into the dark background whileemphasising the true character of reproduced music.
Now, this smooth and in the upper regions airy sounding Japanese is definitely
going to give the lie to the prejudice that all Accuphase components are sounding
bright and analytic. Fact is that Soulution's 720 is slightly more pronounced in thisfrequency range, yet without coming off the straight and narrow.

Variety instead of Asceticism
Most preamplifiers do not dare to appear with useful features. The C-2410 has
got plenty of them.
Once upon a time preamplifiers were "playgrounds" for the child in us. In recent years
however the reduction to the absolute necessary was en vogue, more or less. The
Accuphase is different, though. Which high-end preamp in these days has still got
tone controls in order to iron flawed recordings? Here they are simply switched off if
not needed. Absolute phase also may be helpful once in a while. However since thisfunction is no longer a common feature of high-end CD players, it makes much more
sense at this spot, and it may even be programmed for a dedicated input. The monobutton, too, seems to have fallen into oblivion, although it can be very usefulsometimes. The same applies to balance control, which the C-2410 has got of course.
Even an oh so out-of-date loudness compensation is on board, which is to augment
the impact of basses at low listening levels. And then, have you ever searched aheadphone jack on a new preamplifier only to realise with bewilderment that there isno such thing? That won't happen here! In view of all this the supplied handy remotecontrol is hardly worth a mention. And those who'd think all the buttons and controls
might be a bit too much to deal with can have them simply hidden behind the flap.

The Swiss-made preamp with a price tag at 14,000 Euro (including a phono
stage though, which is optional for the Accuphase) and the C-2410 have beenrunning a close race indeed. Eventually the 720 managed to render the backgroundof atmospheric Jazz recordings on Naim's "True Stereo" sampler with slightly more
precision and could add a tad more sex appeal to the voice of Christy Baron. The
cross-checks were carried out in the 12-dB gain position of the C-2410 which gavethe sound a kind of noble, tender-golden touch. And this is exactly how it could
distinguish itself from the "nakedness" of the Soulution 720, if you know what I mean.
On the whole, the C-2410 is surrounded by an aura similar to a luxury watch,namely nobleness and perfection: there are those fine little lamps glowing, somesmall relays decently clicking and the precise, wonderful feel you get when operating
this preamp is going to thrill you anyway. All this makes the Accuphase stand up fromthe crowd - in fact without any pedantic shadow-boxing.