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In these pages you will find the most complete and advanced range of High Fidelity loudspeakers in the world. And now, of course, Goodmans transistorised Stereo Amplifier - MAXAMP 30 (pages 5-7 and the AM/FM Stereo Tuner - STEREOMAX (pages 8-9) designed to match in performance and style.

Be guided by the comments on each page, relating them to your own personal requirements. In case of difficulty do not hesitate to use Goodmans free advisory service - by telephone or letter - which is equipped to advise you in all matters relating to sound reproduction.
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A special guide for beginners in High Fidelity is on page 4, and an article on the "Mysteries" of Stereo - on page 26.

Next to each Loudspeaker you will find details of the recommended enclosure for that loudspeaker. These drawings are sufficiently detailed for any cabinet maker. On the Price List will be found a list of manufacturers who have submitted samples of their enclosures to Goodmans Acoustic Laboratory and who have received Goodmans' Laboratory Approval for the cabinets listed. Some of the firms listed will make these cabinets to your individual choice of colour and grille-cloth.

On the right is a cross-section of the most popular 12" twin-cone single unit High Fidelity loudspeaker in the world - the AXIOM 301. 12" diameter - 20 watts power - 15 ohms impedance. (For more details and recommended cabinet details see pages 18 and 19.)
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GOODMANS INDUSTRIES • AXIOM WORKS • LANCELOT ROAD • WEMBLEY • MIDDLESEX • ENGLAND
Telephone: WEMbley 1200. Cables: Goodaxiom, Wembley, England. And from Agents and Distributors in most Countries. - A Division of "Radio Rentaset Products Ltd."

All Radio Receivers, Radiograms, Record Players and Tape Recorders contain an Amplifier and a Loudspeaker. In many cases the quality of the amplifier and loudspeaker is governed by considerations of cost and available space, and although the resulting sound quality is adequate for general entertainment it cannot produce the sense of being actually "there" - at a live performance.

To be "there" you need really faithful sound reproduction - High Fidelity - and this can only be achieved by the use of an amplifier and loudspeaker which have been designed - without compromise - for this very purpose. Naturally, the gramophone pick-up, microphone, tape or radio unit which feed the amplifier must be of the same high order of quality, as also must the signal source itself, whether it be a record, a tape, or an F.M. broadcast.

In building up a High Fidelity system you may want to use any or all of these signal sources, but will only need ONE amplifier and loudspeaker system!

Figure 1 shows very simply the main components of a complete installation. The "control unit" is part of the amplifier (often referred to as the pre-amplifier); it contains the controls for volume, treble and bass, etc., and is sometimes physically separate from the main part of the amplifier - though usually sold together - so that it can be installed in a position where the controls are conveniently to hand.

It also contains a selector switch so that you can - by turning the knob to the position shown, connect the gramophone pick-up, tape recorder, radio or other sound source to the amplifier.

All the components shown in the diagram, except the loudspeaker, can be built into the same cabinet, or "built-in" to a room in any way that you wish (e.g. shelves, room dividers, etc.).

The loudspeaker, however, needs its own specially designed enclosure if it is to perform properly. Details of suitable enclosures are given in this manual. The system in Figure 1 is a monophonic system; on page 26 you will find a description of this type of system, also an explanation of stereophonic systems, and their advantages.

Whatever installation you decide upon, you will have to choose a loudspeaker to do justice to the rest of the equipment. Your choice will be governed by three main considerations.
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(1) The amount you are prepared to spend on the loudspeaker system.
(2) The size of the room in which it is to be used.
(3) The possibility of later development of the system.
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A useful guide to the expenditure on the different parts of a High Fidelity system is to divide the total into three roughly equal parts - so that you spend about the same amount on the loudspeaker and its enclosure, as you spend on the amplifier with pre-amplifier, and about the same amount again on each signal source.

The size of your room influences your choice of a loudspeaker. A small loudspeaker (e.g. Axiette 8 or Axiom 10, pages 14 and 17) would be large enough for most sitting rooms, and in addition the enclosure is compact.

However, there is no bar to using a larger loudspeaker for even better sound (e.g. Axiom 201 or Axiom 301, page 18), except that the enclosure is rather larger.

There is often a fear in people's minds that a large loudspeaker will be "too loud". This is quite unfounded as the loudness is under your own control at all times. A large loudspeaker is capable of producing a larger volume of sound than a small one, so it may be worth considering if it is likely that your "Hi-Fi" might later be moved into a larger room. A 12" Axiom is ideal as the basis for a stage-built system (page 21.)

It is very important that a High Fidelity system is "quality balanced". All the components should be ultimately of the same degree of quality: our Technical Advisory Service will be pleased to help you. Incidentally, it is not usually advisable to replace the loudspeaker in a "mass production" radiogram with a High Fidelity loudspeaker, as any imperfections not ordinarily noticeable with a general purpose loudspeaker will be reproduced faithfully - and distressingly - by the High Fidelity loudspeaker.

Power Output: 30 Watts r.m.s. maximum (15 Watts per channel) into an 8 ohm load. 20 Watts r.m.s. maximum (10 Watts per channel) into a 4 or 15 ohm load. Total Harmonic Distortion: Less than 0,3% for 15 Watts per channel into an 8 ohm load at 1,000 Hz - Frequency Response: 20 Hz to 20 kHz -0,5db.
Hum & Noise: With reference to 15 Watts, volume control at maximum, all inputs -55 db overall. Main section of amplifier only -80 db with input shorted. Crosstalk:
With input selector in any position, with unused channel input open circuit, better than -40 db with reference to 10 Watts into 8 ohms on the active channel. Supply: Adjustable for 105-120-200-220-240 volts AC 40 - 60 Hz

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Dimensions.........15" x 24" x 11" deep (38cm x 61cm x 28.5cm)
Frequency Range..........30-20,000 Hz
Maximum Power Capacity........25 watts
Impedance..............4-8 ohms
Finish.........Teak (or Walnut to order)

Dimensions ....27" high x 20" wide x 6" deep (68 x 50 x 15cm)
Frequency range......35-15,000 Hz
Maximum power handling capacity....15 watts
Impedance.......15-16 ohms
Finishes available to order....Teak or Walnut

The overall response curve of the Eleganzia II is shown below. Its exceptional smoothness tells a part of the success story. The fact that harmonic and intermodulation distortion have been reduced to inaudible levels tells another part. Your own ears will provide the happy conclusion.

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The Axiette 8 is the smallest real High Fidelity loudspeaker unit made, arid features a high efficiency permanent magnet system using Feroba II anisotropic ceramic magnet material, enabling a particularly shallow depth magnet assembly to be used. The unique plastic terminated hyperbolic diaphragm, aluminium drive coil and magnet system are housed in a precision diecast chassis of strong and slender design. Enclosure volume requirement - only 3,000 cubic inches. This is an ideal speaker for compact high fidelity installations - whether monophonic or stereophonic. (Use 2 Axiette 8's [each in its own cabinet] for stereo).

In one compact unit: a full 15 watt twin cone High Fidelity loudspeaker, complete with high efficiency HF pressure unit, built-in crossover and constant impedance L-pad attenuator on flying lead for high frequency level balancing.

In one compact unit you have a full 20 watt 12" twin cone High Fidelity loudspeaker, complete with high efficiency HF pressure unit, built-in crossover and constant impedance L-pad attenuator on flying lead for high frequency level balancing.

If it is desired to build an enclosure to suit individual requirements of shape, the A.R.U. will simplify many of the problems normally involved. It is essentially necessary to construct an enclosure of the correct internal volume and to cut two apertures; one for the loudspeaker and one for the A.R.U. The latter is supplied mounted in a wooden frame which can be screwed directly to the edges of the aperture. Four models are available, each having been designed for use with a particular loudspeaker system. Style and shape may be arranged to suit individual taste provided that the internal volume is within ±10% of the value given in the table. The A.R.U. may be fitted into any of the enclosure walls, but the shortest distance between the A.R.U. and the loudspeaker measured round or over the outside of the cabinet should not be less than one foot. There should be no obstruction within 3" of the front of the A.R.U.

The wooden frame is decorative and is normally fitted outside the enclosure, but performance is not affected if the fitting of the A.R.U. is reversed, e.g. in the front panel to present an unobstructed flat surface for covering with a decorative woven fabric material.

All enclosures should be close jointed and rigidly constructed of timber, chipboard, or material of similar or greater density and rigidity, not less than 1" thick. All internal surfaces (except the loudspeaker and A.R.U.) should be lined with 1" thick soft felt or wool, or cellulose wadding, and one or two curtains (see cabinet drawings) of the same material should be suspended from (approximately) the centre of the top of the enclosure, one 2" behind the other. These curtains should be the full internal width of the enclosure, should extend from top to bottom of the interior and should not be fixed to sides and bottom.

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AUDIOM BASS units are designed to cover only the bass portion of the musical register and all the features necessary for providing very accurate performance down to the lowest musical frequencies encountered are incorporated in their design. The necessary mid-range and high-frequency units for the completion of multiple systems will be found on page 20 and enclosure details on pages 18 & 19. For Public Address work and special applications such as Electric Guitars use AUDIOMS in their STANDARD versions-please send for special Guitar Leaflet.

Maximum power handling capacity..25 watts (50 watts U.S.A.)
Fundamental resonance...........30 Hz
Flux density............14,000 gauss
Total flux............269,000 maxwells
Voice coil...........3" (7.6 cm) diameter
Impedance............15-16 ohms
Chassis..............Diecast
Overall diameter...........15" (38.2 cm)
Overall depth...........7" (18.9 cm)
ARU 280 enclosure volume (internal)....9,600 cu.ins.
Baffle hole diameter.........13" (33.8 cm)
Nett Weight.........22 lbs 8 ozs. (10.21 kg)

Maximum Power handling capacity 50 watts(100 watts U.S.A.)
Fundamental resonance (nominal) High Fidelity & electronic organs 30 Hz
Flux density............14,000 gauss
Total flux ........... 269,000 maxwells
Voice coil... 3" (7.6 cm) diameter
Impedance............. 15-16 ohms
Chassis............... Diecast
Overall diameter 18" (45-85 cm)
Overall depth........... (21 cm)
A.R.U. 480 enclosure volume (internal) 11,700 cu. ins.
Baffle hole diameter.......... 16" (40-64 cm)
Nett weight..........20 lbs 4 ozs(9,85kg)

As Audiom 91 Bass but with Fundamental Resonance (Nominal): 55 Hz
Audiom 91/100. Now available - a special version of the Audiom 91 with the ability to handle 100 watts of power (200 watts U.S.A.) with reliability and precision.

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The introduction of stereophonic sound reproduction is the most important single step towards greater accuracy and realism of sound reproduction that has taken place for many years. Until recently every advance that was made simply concerned further refinements of the "monophonic" system, which is still employed in radios, and many radiograms and record players. Always the sound came from one spot only - the loudspeaker system - and no matter how large the orchestra or how wide the operatic stage, all were compressed in size into one small area at the receiving end.

At best, the situation was similar to having one's sitting room connected directly to the concert hall by a small hole in the wall. All sense of the position of the different instruments or the direction of movement of actors was lost. Imagine now that you can put head and shoulders through the hole in the wall. At once the scene broadens, and the ears can take up their function as direction-finders. You are in the concert hall. High Fidelity Stereophonic equipment can do this for you in conjunction with stereophonic records, tape or FM Stereo radio.

The records contain two different impressions in the same groove; these represent the signals from two separate microphones spaced apart in front of the performers. The pick-up used in your stereophonic equipment converts these impressions into two sets of electrical impulses and passes them to two separate amplifiers. Thence they go to separate loudspeaker systems also spaced apart.

You, sitting in front of the loudspeakers, and roughly equidistant from each of them, will have the whole sound picture built up before you, with everything in its right place. If a performer moved across the stage in the original performance you will hear him do so between your loudspeakers. It is hardly necessary to dwell on the vast improvement in realism that is gained in this way. It is similar to the difference between an ordinary "flat" picture and a "three-dimensionall" one (which again is composed of two separate pictures, taken from different viewpoints).

First, of course, a turntable; it does not pay to buy a cheap one; your listening pleasure can be completely spoilt by slow variations of speed (called "wow") or rapid ones (called "flutter"), or by a noisy mechanism which will pass noises like distant thunder ("rumble") through to your loudspeakers. A good turntable ("transcription" type) will be almost completely free from these faults. You may want to play older 78 r.p.m. records as well (stereophonic records 33 or 45 r.p.m.) so a 3-speed turntable is a wise investment.

Next, a pick-up. A good stereophonic pick-up is a light and comparatively delicate affair, but it will not be damaged in normal use. Many models have a removable head, which can be put away safely when not in use. A completely separate pick-up and arm should be fitted for playing ordinary (monophonic) recordings, and this can be more robust, to withstand normal family use if necessary. Specialist advice should be sought as to the exact choice of pick-ups.

The amplifier as mentioned already actually consists of two separate amplifiers though they may be assembled on one chassis. The controls (volume, treble, bass, etc.) for both amplifiers are usually coupled or "ganged" so that there are no more controls than on ordinary equipment, excepting a "balance" control which enables the two channels to be adjusted to an exactly equal degree of amplification. For normal domestic installations an amplifier having a power output of 10 watts in each channel will be found quite adequate.

Finally, the loudspeakers. Since care has been taken all through the recording and reproducing chain to give each of the two signals identical treatment, it is wise to employ two loudspeakers of the same type. Any of the full-range High Fidelity loudspeakers or loudspeaker systems described in this Manual may be used; the exact choice will be governed by the power handling capacity required and by the space which can be given up to the loudspeaker enclosures. It will be noticed that several very compact models are available, and these are of special value when space is limited.

Positioning of the loudspeakers is particularly important. Normally the stereophonic effect will be experienced in a roughly triangular area, the apex of the triangle being mid-way between the loudspeakers.

It is usually impossible to extend this area to cover the whole room, but it will be found quite possible to arrange the loudspeakers so that a small group of people can enjoy satisfactory reproduction without abnormal arrangements of furniture. Optimum loudspeaker spacing will be about 8 ft. for most rooms, with listening positions preferably more than about 10 ft. away from each unit.

Since no two rooms are acoustically alike, precise guidance is not possible, and a little experiment will prove to be worthwhile. Apart from the actual spacing of the loudspeakers some experiment should be carried out with small variations of the direction in which they face.

If, for example, the loudspeakers are located against the shorter wall of a room, start with them both facing straight down the length of the room. Move about the room while playing a stereophonic recording and try to judge the boundaries of the listening area in which the stereophonic effect is satisfactory. Turn both loudspeakers inwards slightly, and repeat the experiment. The object is to try to achieve a satisfactory listening area that corresponds with convenient seating arrangements.

It is vitally important that the loudspeakers should be "phased" correctly. If the connections to one of the loudspeakers should happen to be reversed, the sound picture will not be correct. One of the quickest ways to check for correct phasing is to place the two loudspeakers about 1 ft. apart, facing each other. Put on a stereophonic record of a vocalist, and listen with your head between the loudspeakers, one close to each ear. If all is well, the singer will appear to be in front of you. If the phasing is incorrect, he will be difficult to locate, and there will appear to be a reduction in the loudness of the bass parts of the music. A reversal of the leads to one loudspeaker ONLY will put the situation right.
The diagrams show the essential differences between (monophonic) and stereophonic installations. The Goodmans Stereophonic Amplifier (MAXAMP 30) can be used in a monophonic installation - simply by operation of the Mono push-button.
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• Hierzu ist noch Folgendes anzumerken. Ich war in den 1980ern mehrfach in England und habe die großen Mengen an "Eigenheimen" in Form von extrem schmalen 2 oder 3 geschossigen Reihenhäusern bewundert. In solch ein schmales Haus war ich zu einer Übernachtung auch mal eingeladen. Es ist verblüffend, daß die Häuser innen teilweise nur 3 Meter breit sind. Dafür sind sie 6 oder 8 Meter lang und damit hat es mit den großen Lautsprecherboxen so seine Probleme und Flachboxen sind angesagt. Bei uns hatte diese kleine Goodmans Eleganzia Mini-Box überhaupt keine Chance, denn sie klingt so dünn und schwächlich, das war unakzeptabel. Das konnten die flachen HECO und BRAUN Boxen deutlich besser.

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