FULLER PUTS ALL ITS EGGS IN ONE BASKET

The Fuller Box is an extension which looks natural to the back of a Spectrum. It contains a sound board, amplifier, joystick port and separate cassette EAR and MIC sockets.

The sound board contains the AY-3-8912 sound chip used in many computers and has three programmable pitch tone supplies, plus a noise generator. It also has envelope control to give rising or falling pitched sounds.

The sound board works on port numbers 63 and 95, while the joystick works on port 127. The joystick socket is the standard Atari one and besides the demonstration cassette some commercial software will also work with it, as it is similar to the Kempston joystick.

It costs £30.75 for the basic unit - called the Fuller Box - and the master unit costs £55.75, which includes the speech chip. You can if you wish upgrade to the speech chip at a later date. Fuller Micro Systems, The ZX Centre, Sweeting Street, Liverpool 2. Tel: 051-236 6109. Other shops sell the units.

IT'S IN THE BOX

Peter Shaw takes the lid off the Fuller Master Unit and tells us what he found there.

Fuller, the Liverpool based company who have brought you add-ons for the ZX81 and Spectrum in great quantities in the past, have come up with the goods once again with a very useful peripheral for the ZX Spectrum.

DOES IT MEASURE UP?

The Master Unit itself is built into a tough black plastic box measuring 8cm by 24cm by 3cm. The connector at the back of the Master Unit is strong and forms a good and healthy connection with the Spectrum. The unit also has a connector at the back allowing you to make the outputs you would from the Spectrum itself.

The Master Unit can perform a wide range of fancy tricks although its main feature is speech. The unit is capable of forming a large number of phonemes, all of which are clear, easy to use and, more importantly, easy to understand.

You use the Master Unit's speech facility by sending a chosen number in port 159, ie if you say 'OUT 159,x' where x would be phoneme you wish to be enunciated. The speech demo supplied with the unit was not amazing but was adequate to test the unit's prowess. There are also rumours to suggest that there might be software coming soon from Fuller themselves which could drive the speech unit as well as providing a well written arcade game.

ZAP! POW!! BOOM!!!

The next feature the Master Unit offers is three channel sound - a very useful addition to the limited voice of the Spectrum. Unfortunately, the demo tape to illustrate the capabilities of this facility is not that good, just providing some sample arcade zaps and explosions before giving you a do-it-yourself sound generator program. However, as I found, it is very worthwhile 'doing it yourself' as some of the noises you can come up with are fantastic.

But the unit doesn't stop there! It also has a joystick port for Atari-type joysticks which works very well with a lot of the software I have. The Master Unit also has an on-board cassette interface which enhances all the signals from the Spectrum and allows you to keep both EAR and MIC plugs connected at the same time.

WE SHALL NOT BE MOVED

The Fuller Master Unit sounds amazing, doesn't it - and it is. I'm not going to take it off the back of my Spectrum for a long time.

You can buy the Master Unit for £54.95, or if you would prefer a cheaper version which has all the features of the Master Unit except the speech, you can get one for £29.95.

For more information on the Master Unit or any other Fuller products, get in contact with Fuller Micro Systems, The ZX Centre, Dale Street, Liverpool 2. Telephone enquiries can be made on 051-236 6109.

SPECTRUM SPEAKERS

The word is that attaching any old speech synthesiser to your Spectrum will allow you to have cosy chats together. Henry Budgett determines where this is one of the first signs of madness.

For years science Fiction films and futuristic novels have depicted an era when man and machine can communicate in perfect harmony. The reality, of course, is slightly different. While speech recognition has yet to he fully developed (ACT's latest Rascal notwithstanding), chip-based speech synthesis has been both mastered and available for several years. Until recently the computing power needed to produce human-sounding utterances was substantial. Now almost every home computer is capable of being equipped to talk back to its owner at a price that won't even break the average piggy bank.

SOUNDING OFF

When we speak we produce three distinctly different types of sound. The most obvious are the 'voiced' or vowel-type sounds; oo, ar, ee, and so on. These are produced by air from the lungs making the vocal cords vibrate. The frequency of this vibration determines which vowel sound we hear.

The second group is the unvoiced or 'fricative' sounds; ss, sh, t and ff. Here the air from the lungs rushes past the vocal cords without making them vibrate and the frequency produced is controlled by the positioning of the lips and tongue. Finally there's silence or, to be more precise, the minute gaps that occur within words (for example six, eight) where we change from voiced to unvoiced and vice versa.

FAKING IT

In order to generate speech-like sounds, the electronics designers generally go for one of two methods. The first - and until recently the most common - is synthesis by rule. If the frequencies contained within speech are analysed it's possible to devise a system of rules that allow us to re-create any sound from its basic frequencies.

These 'building blocks' of sound are called phonemes and by using them in various combinations any word can be constructed. The individuality of a human speaker tends to be lost when speech is generated like this but the words can be clearly understood. Because the synthesis rules for each phoneme are built into the equipment, the user has simply to supply a list of phonemes to be spoken. It's then possible to generate complete sentences instantly, simply by calling up a string of stored phoneme commands. In reality these phonemes tend to be called allophones; this is because the various building blocks sound different depending on their positioning within a word or phrase. However the principle's much the same.

The second method for generating speech relies on the fact that the human ear and brain are very good at filling in gaps. The speech we hear over a telephone line is (British Telecom permitting) perfectly understandable. Yet technically the quality - the range of frequencies we can hear - is only one-fifth of what we'd expect from a standard hi-fi system. We understand what's being said only because our brain does the job of filling in the gaps.

With the fall in cost of computer memory it's now possible to convert speech into digital information compressed many hundreds of times by a wonderful mathematical technique called Linear Predictive Coding. The resulting numbers representing the original speech are stored in a ROM. To get any of the stored words out again as speech is easy; we simply give the computer the address in memory of the word and the digital information is recovered and converted back into sound, and because the original speaker's words have been stored, all the personal characteristics remain. That's why Acorn's speech chips for the BBC Micro really do sound like Kenneth Baker.

WHAT'S THE USE?

The commercial uses for speech synthesis are so many and varied that it's just about impossible to list them all. Looking just at the tip of the iceberg it can be used to replace taped announcements at railway stations and airports; in America it's widely used on the telephone system to inform callers of misdialled numbers and engaged or withdrawn services. Speech synthesis units are also being incorporated into cars like Maestros and Montegos as part of the standard instrumentation so, as well as being something of a sales ploy, they can provide warnings the driver can hear without having to take his or her eyes off the road. A major contribution to road safety perhaps?

As far as we are concerned in the home computer and electronic games market, speech synthesis is generally used to enhance games. Scores can be read out and warnings of imminent enemy attack can be given to warn players leaving them free to concentrate on the tactics of the game. Of the five speech units under review here, four of them use the phoneme system and one the stored speech method. Let's take a look at how they succeed in fulfilling their purpose.

SUMMARY

If you're looking for a means of adding a voice to your Spectrum and of incorporating the facility either into games or just for fun, then the Currah MicroSpeech is almost certainly going to be the best buy for you. It's also got the largest number of games already written for it if you prefer to use shop-bought software. Another of its clear advantages over the other units is the addition of a BEEP amplifier for putting the sound through the TV.

For those of you who haven't yet bought a joystick controller or a sound generator and fancy a speech synthesiser at the same time, then the Fuller Box/Orator combination - though expensive - offers the lot in one package.

Serious users of speech output have an equally clear-cut choice. The superior quality offered by the DCP S-Pack's Digitalker chips make this the logical buy for anyone using the Spectrum as an annunciator rather than as a games machine. The manuals supplied aren't good enough by far, but the Digitalker chips are more versatile than you might think, so if you buy this one get in touch with National Semiconductor for the real data.

Of the remaining two units, the Cheetah offers a built-in amplifier and speaker whereas the Timedata unit doesn't; their respective prices reflect this. Neither of them comes close to the overall 'usableness' of the MicroSpeech and they both lack the BEEP amplifier and keyword voicing.

FULLER BOX/ORATOR
Price: £56.00
Fuller Micro
71 Dale Street
Liverpool

HARDWARE: Designed as much more than just a speech synthesiser, here is a unit that fits right across the back of the Spectrum and measures 235mm by 100mm by 40mm. Because the casing masks all the normal socketry at the rear of the Spectrum most sockets are duplicated on the back of the Fuller Box. I say 'most' because the TV aerial lead isn't; you've got to take the box apart to feed this through.

The inside of the box is, to be reasonably polite, a mess! The sound and speech chips are both standard socketed General Instruments devices, but the rest of the construction is a hotchpotch of extra wires and piggy-backed chips.

Still, as well as providing sound and speech the fully expanded Fuller Box also provides a BEEP amplifier with volume control, joystick port and an electronically switched LOAD/SAVE system - which means that you don't have to keep on unplugging the EAR lead while saving programs.

An extra 3.5mm jack socket has been installed at the back of the unit which isn't explained anywhere in the manual, but it turned out to be an extension speaker socket.

SOFTWARE: Activating the speech chip is just a matter of using the OUT statement to pass the relevant allophone number to the Orator. The chip contains 64 standard allophoncs, but quite why Fuller suggest you try a loop from one to 255 is a mystery.

Included are two demonstration programs; one covering the Box in general, the second dealing with the Orator. Listing the program is likely to provide rather more information than just listening to it! imagine gets a posthumous plug for its software, some of which works with the Orator, I believe, and all their joystick games are compatible with the joystick system used by the Box.

MANUAL: It's the sort of paperwork that looks good at first sight but doesn't really tell you very much. If you want more details on the sound chip itself, try the official GI Data Sheet. The manual's explanation of allophones is quite good but fails to expand into real example. That's why it's a good idea to LIST the demo program.

SUMMARY: As an all-in-one unit it's probably quite good for the dedicated games enthusiast who likes the idea of tinkering with sounds and speech. As a speech unit in its own right, it's rather big and clumsy and nearly twice the price of its opposition.