[English Translation Test Accuphase C-2150 & P-4500/ Stereo 12/2019]

The only way is up
Just like the gold rate, Accuphase’s development knows only one direction:
upward. With the new C-2150 and P-4500 pre/power amp duo the company
has once again surpassed itself.

For quite some time we haven’t got hardly any interest on bank deposits or timemoney. Which is why a lot of people are looking for more profit-yielding investments
such as gold, for instance. So how about a high-end system which offers plenty ofsound yield? Especially Japan’s noble brand Accuphase allures by pledging to keep
what the shimmering pale-golden front panels of their components are promising.
Our own experiences, like those of numerous owners, suggest so.
Here the small pre/power amp combo C-2120/ P-4200 had turned out as a special
highlight, scoring a big strike when reviewed in STEREO 1/15 – back then the preconquered the reference class and the power amp was very closely behind. Although
the set price of 14,500 euros (which, in the course of adjustments, recently rose to16,500 euros) was high in absolute terms, buyers got a lot for their money: besides
an exquisite sound quality also the posh workmanship typical of Accuphase, anothertypical comprehensive features list, and finally the stable value preservation resulting
from all this which will make you smile in the event of a resale.
This might indeed be an option for some owners now because the manufacturer fromYokohama is replacing their success combo, and the follow-up models are supposed
to raise the bar once again a little higher. Those who have been watching the soon
50-year company history, know about the engineers’ tough struggle of always
climbing up the quality ladder on tiny rungs by many small improvements to finallymake a real step further up.
Exactly that way we will probably also have to figure the evolution up to the new C2150 and P-4500 duo that will cost approximately 15,900 euros. As usual it takes agood look to identify the newcomers, because in spite of some visual retouching here
and there, they strongly resemble their precursors. This design consistency is also
highly appreciated by the loyal Accuphase fandom.

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Precision owing to AAVA & ANCC
Behind the thick front panels we see the usual design, the common structure of alayout which has remained untouched for decades, whereby the power section in themiddle with its fat mains supply and the power electronics, crowded together on theflanks of the distinctive heatsinks, ought to have the higher recognition factor. But
ever since 2004, when Accuphase introduced their ultra sophisticated “AAVA“ –stands for “Accuphase Analog Vari-gain“ – volume control with the C-2000 for thefirst time (which, as an active part of the amplifier, adds 16 weighted currents in aspecific way to produce thousands of intermediate values to allow an extremely
sensitive and precise level setting), we have been used to the pc board banks in theheart of the preamps from Nippon.
In the C-2150, which runs no less than five separate amp sections simultaneously forthe input buffering, the voltage/current conversion or the opposite direction as well as
the output stage and finally the independent headphone output stage, already thefourth generation has been implemented. And recently an “Ultra Low Noise
Technology“ in the form of a secondary amplifier in the main circuit which is
supposed to further reduce the remaining, already very low interfering components.
With the “Accuphase Noise and Distortion Cancelling Circuit“, abridged ANCC, thedevelopers are aiming at previously unachievable low noise and distortion specs.
Indeed most of the C-2150’s distortion and intermodulation values show three zeros
after the decimal point and thus turn out lower again by up to one decimal power
when compared to the already splendid C-2120. In terms of noise the newbieoutperformed its precursor at least with low signal voltages, i.e. in the normal
listening range, by no less than up to four decibels of increased signal-to-noise ratio.
Quite an accomplishment!
The fact that the C-2150 has a lot of features not found or maybe even missed onother preamps, is a “tangible“ bonus. For instance, besides tone and balance
controls – the latter being realized by the AAVA without additional parts in the signal
path – it offers a convenient mono switch, a 180-degree phase reversal for correcting
inverted audio carriers, and even a switchable record out with tape monitor function.
Add to this the headphone socket plus an ample supply of XLR and RCA inputs.
Super: the pre doesn’t do anything!
Moreover, the C-2150’s basic gain can be pre-selected in three steps. And this gain
setting is more than meets the eye. We recommend the lowest 12 dB setting
because it’s not only totally sufficient for common line level sources, but also, more
importantly, it produces the airiest, most natural sound. At 18 dBs the tone becomesa little more robust and edgier, which may be appealing in particular with pop music.
Switching to 24 dBs, however, will produce slightly glassy mids with a light artificial
touch. This can be checked easily by balancing out the 6-dB level jumps on the2AAVA display, which is precise down to a tenth of a decibel; hence the result isalways exactly the same volume level.
If the new Accuphase preamp didn’t have such a terrific sound, we would notmention this detail at all. But what the C-2150 offers in terms of unfeigned
naturalness – I just can’t think of a more suitable word –, is simply marvelous andoutperforms the talents of the superseded C-2120 once again. Where the latter still
blew a gentle whisper of artificial residual brightness over the notes, this is now
completely absent and the performance happens in a sonorous and homogeneous
way against a pitch-black backdrop. Moreover, the Japanese lacks whatever mightseem to be tarted up, trimmed or re-colored. The absence of tiny noise fringes orartefacts is also noticeable within voices and instruments, which otherwise could
have been attributed to the recording and which we suddenly pick out on otherpreamps simply because the Accuphase doesn’t have them. The sonic events rather
appear to be extremely coherent, absolutely “untechnical“ and credible, giving thebreeding ground for the paradox that the enthusiasm over its appearance is feeding
exactly on the fact that this pre somehow doesn’t do anything.
That an Accuphase plays to the gallery in an airy, nimble manner and with the veryfinest of dynamic shadings is nothing to write home about; it’s a habit. But the factthat it celebrates these qualities with such a tonal coherence as the C-2150 can do,
is indeed worth mentioning. Not only with Maria Pihl’s “Malvina“ from STEREO’s
soundcheck CD VI (which we’ve already listened to umpteen times), the Japanese
was able to deliver a top-level performance with vivid colors, a perfect imaging of thethree-dimensional spectrum and a peerless tonal integrity. Delicately chiselled highbit
files with soft hi-hat tails blowing away into the audiophile nirvana were among theAccuphase’s favorite food.
Well, I am certainly not a fetishist of measured values, but this conjunction of superb
purity and silence with the given, I’m saying it again, naturalness gets me ruminating
as to whether the extra zero after the decimal point is maybe not just academic after
all. Or am I so totally off track now on the rungs of the Accuphase ladder?
Okay, let’s go over to the power amp and its almost sensuously oscillating pointerinstruments which are gently dampened in their return motion. Those who don’t likethis fidgeting can turn it off together with the illumination. The P-4500 also showshalved distortion figures, particularly with the intermodulation values. It may well bethat the 43 per cent of noise reduction, compared to the old P-4200 and specified byAccuphase, were achieved in the balanced input amplifier. However, in the overallmeasurement the amp could not undercut the excellent S/N ratios of the supersededmodel any further.
As usual the power electronics is mounted directly on the lateral heatsinks. Fourbipolar power transistors are run in push-pull mode with two “hot outputs“ perchannel as favored by Accuphase, whereby the consistently fully balanced approachis realized. MOS-FETs serve as ultra long-term stable switches in both speaker3

outputs which are secured against e.g. overload or short circuit by a watchfulprotection circuitry and end in solid terminals.
Goosebumps with “Tres Luceros“We were mostly interested in one question: would the power amp be able to keep up
the sound level of the sensational preamp, or could it possibly turn out as a limiting
factor? The answer: not at all! What the P-4500 yields in terms of conciseness andspeed, is to be congratulated. Like out of nowhere it made the hard, precisely
accentuated vibraphone hits on “Saturday Night“ by the Red Norvo Quartet pop up
between the speakers while providing definition and timbre within those tiny little
explosions and staggering the mumbling audience in the correct depth spacing to theband who was really having a ball.
The Accuphase didn’t care much about over which loudspeaker it was doing its thing.
Whether B&W’s demanding 800D3 or the phenomenal Confidence 50 from Dynaudio– traditionally the Danish speakers love the amps from Yokohama –, the P-4500 wasparading any program so well arranged as if sorted by delicate fingers and also finely
graded in space, but at the same time shining with supple insistence and vigorousdrive. And it was even good for genuine “goosebumps moments“.
For example with the “Tres Luceros“ on our UHQ soundcheck CD IX. After anincredibly realistic guitar prelude we’re mesmerized by the voice of Sandra
Rumolinos which is shortly after complemented in the bass by driving percussions.
The listeners felt shivers going up and down their spines: touché and sunk! Hencethe power amp is equally capable of building up musical suspense like its pre partner.
So it’s true of both Accuphase hits: ”The Only Way Is Up“!
Matthias Böde4