Gradient Revolution MK IV User manual

REVOLUTION
USER UIDE


Congratulations on your purchase of the radient
Revolution loudspeakers which represent the latest in
loudspeaker technology. The radient Revolution is
handcrafted and individually tested in Finland using the
best possible materials available. It will provide you with
enjoyable musical experiences for years to come.
We recommend you to read this manual entirely to fully
utilize the high performance capacity of your speakers.
RADIENT REVOLUTION
3

INSTALLATION
Carefully remove the loudspeakers from their packaging
boxes on the floor, on a soft surface such as a carpet.
· connecting the loudspeaker leads
Connections are on the base of the speaker. Connect the
speaker cables before assembling the top part. Turn the
speaker body gently to the floor (“Woofers are on this
side” marking against the floor). Connect the positive
lead to the red binding post of the speaker and the
negative (ground) lead to the black binding post.
· attaching the feet of the loudspeaker base
The base of the speaker is equipped with adjustable feet.
Attach the feet (3pcs / speaker) to the base of the
speaker. Tighten the feet with nuts using a 1 0mm wrench.
If necessary, the adjustable feet can be replaced by M6
spikes. The bottom part can then be turned upright.
· attaching the spike for the top part of the speaker
Fix the spikes to the top plate of the bottom unit and
adjust the height (35 mm or 1 3/8'') such that there will
be a gap of 1 -2mm between the bottom and top part of
the speaker. (The three black rubber pads of the top part
will be laying on the spikes.) Lock the spikes with the nuts.
The top part needs no tilting.
4

The most accurate stereophonic illusion is obtained if the
listener sits at equal distances to both loudspeakers.
However compared to standard speakers radient
Revolutions, being a point sound source, can be listened
to at a much shorter distance. In this case the stereo
stage will be wider.
The farther from the speakers the listener goes, the more
room colourations will be added to the sound. Thanks to
radient Revolution's directivity properties it can be
listened to at much longer distance without loosing the
accuracy and spectral balance.
Standing waves have different amplitudes at different
places in the room. This means that besides the
loudspeaker placement also the positioning of the
listening spot has equal importance. Near the wall all
standing wave modes are emphasized and heard most
effectively. When the listener moves towards the centre
of the room the amplitude relationships between
different frequencies will change. The lowest room mode
cannot be heard at all in the middle of the room. The best
listening spot will be found between the back wall and
the centre of the room.
A dipole loudspeaker has features that are quite unique.
When the distance between the speakers and the front
wall is similar to that of the listener and the back wall, the
first reflection will be cancelled at the listening place.
LAYOUTS FOR LISTENIN
5

CORRECT PHASIN
The bottom and top part of the speaker can be installed
in three different ways with respect to each other. In order
to guarantee the correct phasing to the listening area it is
important to note that the plug of the top part is in a
correct position. There are two positions to choose
between.
· basic or panel positioning
In this case the midrange & treble driver of the top part is
on the same side as the woofers of the bottom part
(marked with “Woofers are on this side” text). The plug
will be directed to the “Woofers are on this side” text.
· against the wall positioning
In this case the midrange & treble driver is not on the
same side as woofers. The plug will be directed away
from the “Woofers are on this side” text.
6

The radient Revolution speakers can be positioned in a
free space as any panel speakers. In this case it is
recommendable that the distance from the rear wall will
be minimum one meter (3'). In theory increasing the
distance from the rear wall will allow the speaker to go
lower in frequency. In practice however this rule can be
oversimplified. It is always a good idea to try different
distances. Proper starting points are one meter and two
meters.
The basic set-up – where midrange & treble driver is on
the same side as woofers – is a good starting point. First
direct the speakers as in the Fig. 1 . Also try to turn the
speakers towards the listener step by step.
USE AS A PANEL SPEAKER
7
Fig 1 . Basic set- p - where the woofers of the speaker are facing forward.
The distance between the speakers and the wall sho ld be at least one
meter.

It is also possible to direct the bodies as in the Fig. 2. In
this case the low notes are radiated towards the rear and
side walls and the midrange & treble drivers are towards
the listener.
Please note to change the positioning of the plug (turn
away from the “Woofers are on this side” text).
Try different distances (1 m...2m) from the rear wall and
turn the speakers.
In a narrow room radient Revolution loudspeakers can
be positioned quite near the side walls. The
recommended minimum distance is about 50cm (20'').
USE AS A PANEL SPEAKER
8
Fig 2. The woofers can also be directed backwards. Note the position of
the pl g between the bottom and top part.

The radient Revolution has an unique feature for a
panel speaker: it can also be positioned against the wall.
The longer wall of the room is preferable.
When used against the wall the woofers are directed
towards the side wall as in the Fig. 3. In this case
“Woofers are on this side” texts are also on this side. Each
top part plugs will be away from the “Woofers are on this
side” text. The top parts of the speaker (midrange &
treble) will be directed to the listening area.
Smoothness of the bass response depends on the
distances to the side walls and on the construction and
material of the walls. If the side walls are of similar
construction the smoothest bass response will be
obtained when one speaker is twice as far from the wall
as the other speaker. For instance one meter (3') and two
meters (6') from the side walls.
A AINST THE WALL
9
Fig 3. The lo dspeakers can also be positioned against the wall,
whereby the woofers are directed towards the side walls.

If the speakers are placed too close to the side walls the
lowest notes will be attenuated.
The wall positioning gives a unique feature of adjusting
the bass level. When the speakers are taken 5cm...1 0cm
(2''...4'') of the wall, the bass level will be attenuated by
about 2dB. It is also possible to fine-tune the bass by
rotating the speakers slightly (Fig. 4).
When the radient logo on the base plate of the speaker
will not be visible from the listening place the base can
be turned. Remove and tighten the screws with an 4mm
Allen key.
A AINST THE WALL
1 0
Fig 4. For wall positioning, adj st the bass level and tone by moving the
speaker slightly off the front wall and rotating the speaker.

The radient Revolution speakers can also be positioned
in such a way that one speaker is against and another will
of the wall (Fig. 5). Please check that the plugs of the top
parts are correctly positioned.
Attention! In this special case the speaker leads from
amplifier must be reversed in one speaker only (the
positive plus lead to the black binding post and the
negative ground lead to the red binding post). This is to
assure the correct phasing of low notes to the listening
area.
THE MIXED POSITIONIN
1 1
Fig. 5. A mixed positioning where one speaker is attached to the wall
and the other to an open space.

radient Revolution is equipped with two pairs of
binding posts which are located on the base of the
speaker. The red marked plus terminals are linked
together by a jumper. The black marked minus terminals
are connected in the same way. The speaker can be
connected single-wired, bi-wired or bi-amped.
· normal or single-wired
Connect the positive or plus lead from the amplifier to
one of the red binding posts of the speaker. Similarly
connect the ground lead or negative lead from the
amplifier to one of the black binding posts. Connect both
speakers in the similar way. Check that the jumpers
between the similar binding posts are connected and
tightened.
· bi-wiring
For bi-wiring remove the jumpers between binding
posts. Bi-wiring requires two pairs of loudspeaker cables
in parallel between the amplifier and the speaker. One
speaker cable pair drives the bass unit (upper binding
posts) and the other the top unit (lower binding posts).
CONNECTIONS TO THE AMPLIFIER
1 2

· bi-amping
In this case the speakers are driven by two amplifiers.
One amplifier drives the bass part and another the
midrange & treble part of the speakers. Disconnect the
jumpers between binding posts (both channels similarly).
Connect the leads from the bass amplifier to the upper
binding posts. Connect the leads from the midrange &
treble amplifier to the lower binding posts (both channels
similarly). Bi-amping enables the bass level adjustment if
one of the power amplifiers is equipped with volume
control.
Attention: Power amplifiers can be either phase inverting
or non-inverting. If amplifiers you use for bi-amping are
not similar, check this detail in order to get correct
phasing.
CONNECTIONS TO THE AMPLIFIER
1 3

The amplifier power output needed depends on the
listening level, the size of the room and many other
factors having influence on the room acoustics. It is
recommended to use an amplifier of 2 x 50W ... 250W / 8
ohms with radient Revolution. Also higher powered
amplifiers can be used with caution due to their
increased potential for speaker damage.
We recommend to use thick enough cables to ensure
minimal signal losses in transfer from the amplifier to the
loudspeakers. A minimum thickness of 1 .5mm2 is
recommended for the speaker cables of five metres or
shorter. If the cable length exceeds five metres a thicker
cable is recommended.
THE CHOICE OF AMPLIFIER AND CABLES
1 4

The efficiencies of Hi-Fi loudspeakers are well under 1 %
(typically under 0,2 %). This means that over 99
percentage of all power produced by the amplifier will
be converted into heat in the loudspeaker. Excessive heat
may give rise to the over heating of crossover
components and driver voice coils. When the power
handling capability of the speaker is exceeded it is likely
that the tweeter voice coil wound of a very thin wire will
be burnt first.
radient Revolution loudspeakers can handle high
powered peaks of short duration. Music of varying
dynamics (even huge) can be listened to at a high volume
level. If the music sounds continuously loud (heavy rock,
etc.) and it is played for a long time, it is highly probable
that the heat builds up faster than the drivers can
dissipate it. The result of this may be damaged drivers.
A loudspeaker can be damaged also by low powered
amplifier when over-driven (loaded). In this case amplifier
will clip and cause high ordered distortion components
(high notes) which easily burn the treble driver voice coil.
POWER HANDLIN
1 5

· rotatable dipole bass
The bass part of radient Revolution loudspeaker
consists of two 300mm custom made long throw
woofers. They are assembled on an open baffle giving
the low frequencies a "figure eight" or dipole radiation
pattern similar to most panel loudspeakers. These two
woofers operate at frequencies below 200Hz.
An ordinary box speaker radiates in all directions at low
frequencies. This has the unfortunate effect of generating
standing waves in all dimensions. In the typical listening
room, standing waves distort the sound at frequencies
below 200Hz. radient Revolution does not excite
standing waves between the floor and the ceiling, it can
only generate them in the direction of the radiation
pattern.
The woofer section of the radient Revolution can be
rotated and directed in three different ways, to minimize
undesirable standing waves in the listening area. This
ability to "tune" out standing waves in the bass is unique.
The result is a smooth articulate bass response which has
correct musical pitch and dynamics.
· acoustic resistance enclosure at mid frequencies
Frequencies higher than 200Hz are reproduced by the
top part of the speaker. It employs a coaxial midrange &
treble driver which is a virtual point source. The main unit
is a 1 76mm glass-fibre coned driver which receives its
radiation characteristics from an acoustic resistance
enclosure.
A BRIEF DESCRIPTION OF TECHNOLO IES
1 6

Thanks to the cardioid radiation patter the speaker
radiates frequencies over 200Hz mainly to the forward
direction. The backward radiation is dampened most
effectively being in power only one percentage of the
forward radiation. Unwanted reflections from the nearby
boundaries will be minimized and the midrange will
sound clean without colourations.
· acoustic waveguide at high frequencies
The aluminium dome tweeter placed at the apex of the
cone uses midrange diaphragm as a waveguide to
control treble dispersion. The resulting radiation pattern
at high frequencies is therefore very similar to that of the
cardioid midrange. Of course the tweeter is equipped
with a voice coil/ magnet system of its own.
· a point source at mid & high frequencies
A point source is generally accepted as an ideal sound
source. It enables excellent frequency response and
phase properties over a wide listening window. The result
of this will be stable and accurate stereo picture with
good three dimensionality. The quality of a recording will
be easily discovered.
A BRIEF DESCRIPTION OF TECHNOLO IES
1 7

TECHNICAL SPECIFICATIONS
1 8
Model:
Loading principle:
Radiation patterns:
Frequency response:
Drivers:
Crossover frequencies:
Dimensions (WHD):
Weight:
radient Revolution MK IV
Bass:
open baffle (f<200Hz),
Midrange:
acoustic resistance
enclosure (f>200Hz)
dipole (bass), cardioid
(midrange & treble)
50-25000Hz +/-2dB
-6dB@30Hz.
2×300mm long throw
woofer, 1 x1 76mm glass-
fibre midrange, 1 x25mm
coaxial Al-dome
200Hz and 2800Hz
36 × 1 02 × 32cm
30kg
Designed and manufactured in Finland
by radient Labs Ltd.

radient loudspeakers are manufactured from high
quality materials and components. The performance of
the drivers used have been tested before the assembly.
After the assembly a precision measuring system ensures
that all speakers are of a similar high standard. The
inspection marking and the serial number are located at
the top of the bass unit.
QUALITY CONTROL
1 9
radient Labs Ltd Kisällintie 8 FI-061 50 Porvoo Finland
www.gradient.fi
COPYRI HT © 201 9 RADIENT LABS. ALL RI HTS RESERVED.

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