Here - Quad

AMPTIfIER
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ABOVE: Quad has endorrred tu Integrated with thre€ line and one MM/MC phono
inpuLr, a tape input and a single set of goldflated 4mm speaker cable outlets
Of course, some ofthe mono
vs. stereo mixes are so radicallY
dissimilar that the differences are
bound to be pfonounced. But the
tracks known to differ minimallY
allowed the Quad to demonstrate
the way it does not mask
subtleties. (Note: You do have to
examine the booklets that came
with The Beatles cDs to find out
which tracks were merely mixed
down to mono, and which differ
extensively. A mono button on the
Quad would have helped!)
IF ONI,Y...
It must be said that the Quad ll
Classic lntegrated exceeds its
specifications and its mission
statement, but it i5 not some sort
of magical solution to allyour
electronic needs. Upon feeding
it Koetsu and Transfiguration
moving coils, lwished I'd had a
phono stage with variable settings
something clearly beyond
its price point. The extreme
treble was slightly softer than I
anticipated, although this may
be regarded as a virtue if You
are seduced {as I was) bY the
way this amplifier sounds like its
loudspeaker antecedent. I miss a
remote. And lwould have loved
a way to separate preamP from
power amp.
But, given that labsolutelY
adore this product, those are
minor, operational concerns. OnlY
slightly more vexing is the Price,
which places this at c 1200 more
than, say, the (admittedlY Prosaiclooking)
Audio Research VSi60,
while it costs considerably more
than the various models from
Prima Luna. lf this honey of an
integrated amplifier were on sale
at f3500 or even 83900, it could
cause a stampede. At €2900, it
could rule the world.
Despite that minor concern,
though, I have no qualms
over raving about the Classic
Integrated. After all, there afe
some manufacturers out there
asking f4500lor a metre of
cable. The Quad's looks alone
could seduce the credit card from
my wallet, while the confident,
robust, involving sound would
render it inseparable ffom mY
listening room.
More than anything, I look
upon it as purely, utterly and
totally 'Quad', regardless of the
place or its date of manufacture. O
';,:'ii;.;lt,i ,f '
'.l. i ,'..1;r.,
1,'I
lI there is anything unexpected
about Quad's integrated, it's the
palpable'reafwodd' Power: this
baby drove Wilson soPhia 2s
with aplomb. Tim de Paravicini
squeezed out as much grunt as
a brace of KT66s-Per-side can
deliver, without alterinq the
warm, seductive character of
a circuit nearly eligible for its
bus pass. Truly a Quad for the
21st Century, and in a more
convenient package than You can
imagine, it's a triumph.
Sound 0uatity: 860/o
QUAD II CLASSIC lNT. E45oo)
Whileretaining manyof the original Quad ll hallmarks'
including its push_pull KT66 output configuration and singleta
D outout transformeE, this 'integrated' version of the
1950r7os classic k twice as powerfLll if Quad's 2x25W ratinq
is any guide. In practice it does betterthan that, offering
2x32W8ohm. However, while the tta nsformers in the original
design were seemingly optimked for an intetmediate 6ohm
load, this Classic Integrated mod€l gives off its best into Sohm'
the outputfalling to 2x21q4ohm i23W underdynamic
conditions - s€e graph 1, belowl.The outPut impedance k
imoressivelv low at "0.2ohm for a transformercou pled amp'
a figure broadly maintained from 2OHzthrough to 2okHz.
As a result. the amplifiels response holds up verywell into
Sohm (-0.8d B/2okHz), 4ohm (-0 95d8/20kHz)and 2ohm
{-1.5dB/2okHzloads, despitethe shortfall in power output
Noise is lowthe classic Integrated achieving an A-\^/td
S/N tatio of 88.SdB (re. OdBW) and a tesidual hum and noise
of-76.2d8V (just O.1smv unwtd). Distortion is also carefully
judged in this design isee Graph 2, belowl, falling as low as
0.025%throuqh bass and m;drange at low/8ohm but dsinq
to 1Ox this figurc at very high {20kHz)treble frequencies. The
output transformers also saturate quite quickly below 2oHz
where distortion shoots up to 20_30%
ftom 10 Hz down to 5 Hz
at iust 5w8ohm -so bewaretfut infrcsonic bassfrom CD or
LP sources does not robthe Classic of its enetgy! Reade6 are
invited tovjew a comprehensive QC Suite test report forthe
Quad ll Classic fntegrated by navigating to wv'rw.hifinews.co.uk
and clicking on tbe ted 'download' button. PM
trl
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Dyrtuic Pov.r oual, >>
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ABOVE: Dynamic power output versus distortion into
8ohm {black trace),4ohm (red}, 2ohm (blue} and
lohm (green) speaker loads
E
Fr.qu.ncy>>
l!!l
ABOVE: Distortion vs. frequency from 20Hz to 2OkHz
(1OW/8ohm). Distortion increases markedly at lower
frequencies, reaching >2o%from 5-10H2 atjust 5W
Power output (