Datasheet

a 7.1 surround rig is unnecessary, the ‘spare’
left and right back channels can be used for
a separate 2.1 stereo system that shares the
same subwoofer.
As with the KH120A, the rear panel
carries lots of switches and controls to
customise the configuration. Slide switches
provide a ground lift, and enable or disable
the bass management — either on all the
outputs, or just on the ‘back’ channels.
When the bass management is engaged,
an 80Hz high-pass filter is inserted into
each channel output, removing bass from
the satellite speakers and routing it to the
subwoofer instead (along with the LFE
signal, if present). Another switch turns
on an 80Hz test signal to help adjust the
subwoofer phase (adjustable in 45-degree
steps) to match the satellite speakers.
A rotary control adjusts the subwoofer
sensitivity, and a slide switch adds an
additional 10dB of LFE gain to adhere
to the Dolby Digital requirements. Four
more rotary controls provide a single-band
parametric equaliser and a low-cut filter to
help with room-tuning and optimisation.
The parametric EQ can be tuned between
20 and 120 Hz, with a gain range of +4dB
to -12dB. Its Q can be set between 1 and
8, while the filter provides up to 12dB of
attenuation below about 30Hz. A rotary
mode switch determines how the bass
management works for the subwoofer
signal, with options for 80Hz and 120Hz
filtering, or no low-pass filtering at all. The
sub also has the ability, when in the 80Hz
mode, to route any LFE signals above 80Hz
have the courage or confidence to produce.
The frequency plot confirms what my ears
were telling me: that the response is very
well controlled without any mid-range
forwardness. Inevitably, there is some port
resonance at about 60Hz, which is revealed
clearly in group-delay and waterfall plots,
but the rest of the time-domain response
is very tidy. The directivity plots indicate
how the MMD waveguide helps to control
the vertical directivity, in particular, which
minimises the interference caused by
sound splashing off a console or desktop.
Harmonic distortion is pretty respectable
down to about 100Hz, below which it rises
significantly, as it does with most speakers.
KH810 Subwoofer
The pictures of the KH810 subwoofer make
it look like a compact, almost cubic box,
but nothing could be further from the truth!
The KH810 is huge and heavy — I’m talking
about a 26kg box measuring 360 x 330 x
645mm (HWD). The MDF cabinet is ported
with a pair of triangular vents in the bottom
corners, and a diamond Neumann badge in
the top-left corner. The specifications quote
a bandwidth of 19Hz to 300Hz (±2dB), and
its internal 200W amplifier is capable of
producing 112dB SPL at one metre.
The rear panel is very busy, because
the KH810 incorporates a full 7.1-channel
bass-management system. Consequently,
there are 16 XLR sockets providing inputs
and outputs for left and right front, left and
right surround, left and right back, centre
and LFE/sub. Cleverly, in situations where
The last switch
sets the output level achieved with an input
of 0dBu. The options are 94, 100, 108 or
114 dB SPL (at one metre), and a rotary gain
control allows the input to be attenuated by
up to 15dB to fine-tune the actual volume.
I used these monitors in a variety of different
rooms and generally found the 100 or 108
dB SPL settings provided the perfect level
for them as nearfields or mid-fields when
working on speech and acoustic music.
Despite the compact size, the KH120A
punches well above its weight, with the
spec sheet quoting a free-field frequency
response extending between 54Hz and
20kHz (±2dB) — which is a remarkable
LF extension for monitors of this size. The
headline maximum SPL figure is 111dB
at one metre, although a more useful
real-world figure is 92dB (C-weighted) at
2.3 metres, tested with pink noise — rising
to 94dB SPL if partnered with the KH810
subwoofer. That’s a pretty healthy output for
a speaker that you can pick up in one hand!
K+H are very much an engineering-led
company, and this is clearly evident in the
impressive manual, which includes a full
set of test and measurement plots —
something that very few manufacturers
Compact, active two-way speakers are
plentiful, but for real quality monitoring the
current benchmark models start at around
£1000, which is precisely where the KH120A
has been positioned. This puts it in the midst
of competition like the Genelec 8130A, the
Quested S6R, the Focal CMS65, Dynaudio
BM6A MkII, and the passive PMC TB2S+, all
of which are very competent small monitors
separated only by personal tonal preferences.
Alternatives
The KH810 subwoofer has enough inputs and outputs to accommodate a 7.1-speaker surround-sound
setup, and the controls allow for comprehensive monitor-system configuration.
ON TEST
NEUMANN KH120A & KH810
138
April 2012 / www.soundonsound.com