icon Audio David Shaw FRm Series User manual

icon Audio
Instruction Manual for:
FRm 3 Loudspeaker
Contents
1 Introduction
2 Final inspection
3 Connections and filter box
4 Initial Positioning
5 Quick Set up guide
6 Getting the best from your FRm 3s
7 More Advanced Tuning
8 Design Background
9 Maintenance
10 Specifications
11 Guarantee
12 Packing instructions
Introduction
Thank you for buying a pair of FRm 3 (Full
Range modified) loudspeakers. These
loudspeakers are unique in that they are very
flexible in their use, The bass in particular and
midrange/treble performance is adaptable to a
range of different situations.
Please read the “set up” guide when first
using to become familiar with the options
available to tailor their use to your particular
system and room acoustics.

Page 2
2. Final Inspection - Your Guarantee of Quality
To assure you of optimum performance and reliability, these loudspeakers have passed our
rigorous final inspection and listening test by the Icon Audio team in Leicester.
Date …../…../…..
Model …………….
Veneer …………….
Serial Number …………….
Customer ……………………………
Check cabinet finish ……….
Internal wiring check ……….
Filter wiring check .………
24 hour listening test ……….
Sound Quality ……….
Channel Balance ……….
Box Contents:
1x FRm Manual ……….
2x Loudspeakers ……….
2x Speaker cover ……….
2x Filter box (for 2 drivers) ……….
4 pairs short cable ……….
8x Spikes ……….
2x Copper links ……….
Upgrades:
Internal Silver wire ……....……….
Filter capacitor ……………….
Capacitor grade (Audio) ……….
Other
………………………………
……………………………………
……………………………………
……………………………………
……………………………………
……………………………………
……………………………………
Signed off by ……………………….
Notes:

Page 3
3. Standard Connection of filter box
4. Initial Positioning
Ideally your room shape and size will be similar to
one of the diagrams above. If not try to get an
angle of between 60°-90° from your listening
position, between 1ft (33cm) and 3ft (1 m) away
from the wall. The closer to the wall the more bass
will be reflected. Sitting at or near the centre of the
room will reduce the bass you hear so careful
positioning should enable you to obtain the bass
balance desired.
This is showing the
Standard method of
connection suitable
for most situations for
more advanced
options see section 7

Page 4
IMPORTANT READ THESE NOTES THROUGH FIRST!
5. QUICK SET UP GUIDE
1 Unpack each speaker carefully. Make sure
that it is in good condition. If not report to your
dealer. It is important that you keep the packaging
for warranty/service return/shipping
2 Position in approximate listening position
according to diagram (page 3). Fit Spikes (if
required) after final positioning.
3 Connect amplifier to filter box. Position at the
rear of the FRm speakers. Use good quality multi
strand speaker cable. (Although anything thicker
than say QED 79 will have no advantage)
Connect to “Input” “+” and “-“.
4 Connect filter box to speakers, using supplied
cable(s). The FRm 3 model uses two pairs of
cables; connect the top speaker terminals to those
marked “Upper” on the filter box. And the lower to
the terminals marked “Lower” on the filter box.
5 Check the polarity of “+” & “-“ of both
speakers at all connection points on both
speakers. This is essential for correct
performance. Red is “+”, Black is “-“.
6 Fine tune positioning by looking at each
speaker from your listening position. The
speakers should be facing you directly, so that
you cannot see either side of the cabinet. Each
speaker ideally should be exactly the same
distance away.
7 “Toe in”
Some loudspeakers sound better if they are
angled towards the listener, we have found that a
more stable image is obtained if the speakers are
not angled (see diagram) but this is personal
preference.
8 Running in
If the speakers are cold, they will take up the 48
hours to normalize. The “running in” period is
approximately three months, as the high quality
cone suspension takes longer to “free up”, and to
“run in” and for the cone material to its optimum
sound quality. Do not play them excessively loud
for a few days. The more you use them the better
they will sound. Full range music of any kind with
a good bass content will help. A noticable
improvement will be heard after a month. After 3
months of use the speakers will be at or near their
optimum. When the speakers are in a cold room
they may take 30 minutes of use to “warm up”
even when “run in” (this is true of all speakers).
Stray magnetic fields
The speaker drive unit magnets have magnetic
fields that extend beyond the boundaries of the
cabinet. We recommend you keep magnetically
sensitive items (computer discs, audio and video
tapes, swipe cards and the like) at least 0.5m from
the speaker.
6. Getting the best out of your FRm 3 loudspeakers
After you have assembled your Hi Fi system you
naturally will want to get the best results. You
probably know there is an intimate relationship
with your amplifier. An ideal amplifier for the FRm
speakers is a low to medium powered valve or
transistor amplifier. The power needed will vary
with room size and the desired maximum sound
level. Ideally between 8 to 50 watts will be ideal.
Single Ended “Class A” amplifiers, and push-pull
amplifiers with low or no feedback work very well.
(Transistor amplifiers are usually high feedback).
Larger “Class A/B” Push Pull valve amplifiers will
also work well as you will be using mostly the
“Class A” part of the power curve. “Pure Triode”
valve amplifiers are considered by many to have a
more pleasing sound, These could be amplifiers
using valves (or tubes) such as 2A3, 300B, 845,
805, 211, 6C33 etc.
If your valve amplifier uses 6L6, KT66/88/120/150,
EL34, EL84, 6550, (and other pentode types) it is
probably using the “Ultralinear” method which
gives 90% of the power of Pentode operation and
90% of the quality of Triode operation. You could
consider converting to 100% Triode. Icon Audio
and most good valve engineers can perform this
easy and reversible modification for a relatively
small cost. (More information on request) The
10% difference between “Ultralinear” and Triode
IS very noticeable, the small power loss will hardly
be noticeable. Most Icon Audio amplifiers using
pentode valves can be switched into “triode
operation, plus some other brands.
Listening Room
Although often overlooked, this is the final
component of your system which can “make or
break” the results you get. For example a room
with tiled floor, lots of windows will sound hard
and bright. Whereas a room with a carpeted floor
and lots of soft furnishing will have a more
pleasing and accurate sound as the sound
reaching your ear is mainly from the speakers,
and not as a result of reflections from the walls,
floor, windows etc.
When you consider the trouble you have taken to
set up your system, the small investment in time
and trouble needed to correct listening room
problems can give a huge improvement in
listening quality.
It should be remembered that most loudspeakers
are developed in an “anechoic chamber” where no
sound is reflected at all!
Obviously many rooms fall in between these two
extremes, and many things can be done to
improve hard bright rooms such as closing
curtains, hanging drapes, fitting acoustic tiles,
laying rugs and mats. These will all absorb and
break up unwanted sound.

Page 5
Listening Position
This is the final link which again can make the
difference between a “good” system and an
“excellent” system, and is relatively easy:
Position the FRm’s similar to the page 3 diagram
and listen to the bass, if it is a little “boomy” bring
the speakers forward a little at a time until the
desired bass quality is achieved. Moving your
speakers further away from the corners whilst
keeping the same distance from the rear wall may
also help as more bass is reflected from the
corners than the rear walls. Also consider your
listening position. The least bass will be heard in
the centre of your room so sitting closer to the
rear wall will increase the perceived bass. Try not
to have your speakers too far apart; this can
“stretch the image so that it is not well defined. In
an ideal set up you should also be able to hear a
well defined centre image and even sounds
“outside”your speakers. Ideally about 1m from the
side wall is required to get the full effect. When
correctly set up you will be able to hear sounds
that appear to be coming from either side and
even from behind of you! (Depending on the
recording).
Whilst it may not be possible to do all the things
suggested here, a compromise may be found
which is acceptable to the room layout and other
functions of the room, sometimes on a temporary
basis e.g. for serious listening, moving your
speakers to a better position, or moving a chair or
sofa out of the way. Please experiment, as a small
adjustment may make a noticeable difference.
7. More Advanced tuning
In most situations the “Standard” wiring will be
found to work well as described above. In which
case the installation is complete.
Filter 2 use:
Should a more “forward” presentation be desired
insert the supplied copper link between the “Filter
2” terminals. This has the effect of “lifting” the mid-
range and treble slightly.
The FRm 3 is very versatile and several other
combinations are possible which may suit your
equipment/room/musical taste better. All that is
necessary is to reconfigure the wiring as shown.
When making changes you may need to switch
your amplifier off, although this is not necessary
with Icon Audio amplifiers
When auditioning changes it is advisable to play
several pieces of well known music to judge the
difference in overall balance. In some cases you
may find little difference.
Bass unit as Passive Radiator:
Here the bass from the upper unit causes the
lower unit to act as a passive radiator. The bass
will be less solid but still have good extension on
low notes.
Bass unit as Damped Passive Radiator:
Here the bass will be much tighter, ideal if you
want to limit any bass “boominess” due to room
acoustics. It will require a short piece of solid or
stranded copper wire for the “link” (not supplied).
Parallel Full Range:
Ideal for a very large room where maximum
efficiency is required. Slightly warmer
presentation, with full range slightly lower
impedance. Not ideal for very low powered
amplifiers.
Series Connection
This method gives a 16 Ohms impedance with
probably the generally lower efficiency and a
lower bass balance, generally sounding more
neutral.
8. Background to FRm 3 design
We have been making all kinds of valve amplifiers
since 2000, and have become aware that many
modern and some older speakers are very
complex in terms of their crossover (or dividing
network) which is usually out of sight, inside the
cabinet, this forms a barrier which can seriously
degrade the output of amplifiers, especially the
lower powered simple designs where much of the
simple purity is lost.
On the other hand, some of the “full range”
speakers available on the market do have great
purity and efficiency, but can have an
unacceptably “forward sound” in the midrange,
which makes them less than ideal for full range
and especially popular music.
So we set ourselves a goal to develop a
loudspeaker system that uses a full range drive
unit, large enough to deliver deep bass from a

Page 6
simple cabinet (with lower cost advantage), but
also with a very pure mid-range and extended
high frequency.
The final design the 8” FRm unit was achieved by
many hours of listening to many kinds of music
(mainly acoustic) and fine tuning by our listening
panel.
Any full range speaker will always have the
disadvantage of a frequency peak in the upper
midrange. To counter this we have used a very
simple circuit to attenuate this frequency peak so
the tonal balance is more linear. This is not a
crossover, instead it is a filter for the upper
midrange. This has the effect of raising the
impedance of the speaker and therefore limits the
output at certain frequencies, this way no power is
wasted, having the advantage with lower powered
amplifiers that this unused power is then available
for another frequency especially bass, thereby
improving the performance and lowering the
distortion of the amplifier.
The FRm 3 is the largest of these systems having
two drive units, designed with larger rooms in
mind or where extended deep bass is important to
the listener. And if necessary with bigger
amplifiers capable of a very large sound output.
If you consider, full range loudspeakers have a
great deal to offer compared to a conventional 2
or 3 way. Going back to basics, the only reason a
loudspeaker has more than one unit is because
one has difficulty covering the whole audio
spectrum from which is normally thought of as
20Hz to 20,000 Hz. The reality is however that the
additional complexity of using more than one
speaker can cause problems in other ways which
although not as obvious as poor frequency
response, can make life difficult for the amplifier
driving the speaker, especially lower powered
valve amplifiers. For example a typical 2 way
speaker uses a larger speaker for bass and
midrange with a small dedicated “tweeter” to
reproduce the treble part of the spectrum. All well
and good you might say but if we consider exactly
what happens the problems in doing this become
more apparent:
If we ask a loudspeaker to reproduce a rising
frequency there will become a point where the
crossover will limit the energy being supplied to
the bass unit and will start to send it to the
tweeter. At that point both speakers will try to
reproduce that note and therefore there will be
distortion and confusion to the ear as time delay
and phase shift start to add distortion to the way
that frequency is reproduced. The result is not a
“bad” sound but a loss of detail in the stereo
image. The test equipment used by a
manufacturer will be looking for harmonic
distortion and a flat frequency response, so if the
speaker passes those tests it will be classed as
“good”. The reality is that we are not sending
simple frequency sweeps to a speaker, but
complex musical information. A single note from a
piano, violin, human voice etc will contain low,
medium and high frequencies which will be split
into two or three parts by the crossover for the ear
to put back together again. Now although the
frequency information will be correct some
essential phase and detail will either be lost or
misunderstood by the time the three parts are
separated by the crossover, reproduced by the
three speakers for our ears to try and understand
the original meaning.
Musical information which often consists of the
orchestra and singer(s). Obviously one device (i.e.
the microphone) is able to pick up all these
sounds at the same time as we use only one
microphone for the whole frequency range so a
“perfect” loudspeaker would behave in the same
way. But because is the “norm” to have a 2 or 3
way speaker most people assume that this is
essential. This is not true!
Our full range loudspeaker is specially developed
to reproduce the whole of the audible range of
sounds. You will immediately hear that this has a
kind of purity and immediacy that is lacking from
multi driver speakers.
In the past we have had experience working with
and making cabinets for full range loudspeakers
such as Fostex, Lowther and older Wharfedale
and Goodmans designs. These are still highly
regarded by many audiophiles as having qualities
which modern designs seemed to have lost.
What we are aiming to achieve with the FRm
series is a Full Range speaker that is a
combination of the best of old and new.
A small disadvantage of FRm 3 speakers is that
they are more directional than conventional
speakers because the treble radiator is “recessed”
in the cone. This is similar to Tannoy “Dual
Concentric” speakers and Electrostatic types. So
careful positioning is needed. When listening the
drive units should be at “ear level”. In some cases
it may be necessary to tilt the speakers back
slightly. This may be done by adjusting the spikes
lower at the back, or not fitting the rear spikes.
This will give increased definition of the sound
stage. You should then be able to “pin point”
instruments left, right and centre and even
“outside” the speakers with excellent “front-back”
definition as well.
Dynamic Range;
Due to the “no power wasted” design and the lack
of a “crossover” a much larger amount of the
amplifier power is converted into sound, giving a
dynamic range much larger than conventional
designs. This is especially noticeable when
comparing to electrostatic types.

Page 7
9. Maintenance
The FRm series requires little maintenance. If the
loudspeakers have been well looked after and kept in a
dry environment they should give many years of service
with no problem. The connections on the rear, to the
filter box and amplifier will benefit from “breaking and
making” at least annually by disconnecting and
reconnecting several times to ensure a good low
impedance connection is maintained. Copper wire is
prone to corrosion, the exposed wire should be bright
and shiny, dull corroded wire will have a high resistance
and degrade the sound. The drive units are quite strong
and are able to deliver a high level of sound in a medium
to large room. Handling power is approximately 75 watts
of undistorted speech and music (NOT continuous sine
wave). Amplifiers of up to 100 watts may be used.
However the FRm series does not have any protection
against abuse and accidents so beware of “switch on
thump” and other accidental surges.*
Cabinet Care
To remove dust we suggest gentle wiping with a slightly
damp cloth with an occasional polish. The cabinets are
real veneer. Avoid sunlight as this will both fade the
natural colour and damage the drive unit, UV light in
sunlight will cause premature deterioration of the cone
roll surround and may distort the shape of the cone
causing mis-alignment and failure of the unit. *
*These faults are not covered by the warranty.
10 Specification & Features
Typical values
•Icon Audio developed and manufactured drive
units.
•Rare earth alloy high frequency dome
•Custom paper cone for optimum bandwidth
•Long throw coil and roll surround for extended bass
•94db approx output, 1 watt @1 meter (2.83v)
•Designed and tested with low-med power valve
amplifiers
•Suitable for amplifiers 6 to 100 watts, @ 8 ohms
•Audio grade MDF cabinet
•Real wood veneer finish
•Standard finishes rosewood cherry or walnut
•Plinth and adjustable spikes included
•FRm 3 Size in cm W29, D28, H104, 29kg ea
•4n Copper wire voice coil
•High purity 99.99% copper multi strand internal
cable
•Low impedance choke
•Soldered internal connection for long term low
resistance
•Supplied filter box with high quality components
•Heavy gauge custom chokes for low impedance
•All hand wired point to point without printed circuit
•Nominal DC impedance 7Ω (full range unit)
•Freq response FRm3 30 - 18kHz (room dependant)
•Solen/SCR hi fi audio capacitors (recommended
Jensen upgrade Copper foil upgrade available)
•Gold plated Input & speaker terminals
•ROHS compliant

Page 8
11 Guarantee
Thank you for purchasing one of our products. We
trust you will be pleased with it.
These loudspeakers are guaranteed by the
reseller you purchased from for 12 months from
the date of purchase for parts and labour,
excluding shipping. Please keep your receipt as
proof of purchase, this may be needed.
All units are individually tested for performance for at
least ten hours before despatch to you. In the unlikely
event that you believe the unit is not functioning
correctly, it may be helpful to contact us first as we
may be able to assist you. Then we would request
that you return the item to your dealer.
You are advised to inform us of any change of
address or change of ownership in order that we may
keep you up to date of any upgrades or
improvements. Check our website.
Exclusions
Natural veneers are subject to small flaws. Some
fading and slight cracking is normal over time. We
reserve to reject claims for faulty units where tests
reveal abuse or overload (e.g. burnt out voice coils).
Claims for any damage should be reported to the
sender and/or shipping company must be reported
within 24 hours of receipt.
This loudspeakers is designed for normal domestic hi
fi use. They are not guaranteed for commercial,
Public Address use, or use in other situations without
authorisation. The guarantee becomes void if the unit
has been modified in any way not approved by Icon
Audio.
12 Packing Instructions
It is essential that the original box and packing be
kept in good condition, as this provides vital
protection from damage during transit. Please do
not write on box, but use labels. Please note we
are unable to supply replacement packaging.
•Re-use the supplied plastic bag to keep the
speakers clean and free from dust/damp.
•The spikes should be removed and packed
so that damage will not occur to the cabinets.
•Do not store in damp conditions as the
cabinet and drive units will be damaged.
•If the speakers are shipped insurance is
desirable due to the high unit value.
icon Audio UK LTD
351 Aylestone Road Leicester LE2 8TA UK
www.iconaudio.co.uk
Phone [phone]
Cell [phone]
Email: [email protected]
2020-02-19 G version