In true Bates Motel style, JON BATES becomes a multitasking person(ality). He’s got all that readers’ post to deal with, plus an indepth (deeper than the swamp) review of the TX81Z tone module and its voicing program. It’s a hard life, Jon!

FOR SOME TIME now the Yamaha FB01 tone module has been — along with the Casio CZ101 — the favourite budget approach to sound creation from a Spectrum. Regular readers will no doubt have noticed that we have had plenty of correspondence and programs for both. Just over a year ago Yamaha launched a new module, the TX81Z, which certainly outshone the FB01 in many areas, notably its ability to use a different waveform for one of the operators. I will go into more detail... (Good — Ed.)

Usually FM sound generation uses pure and simple sine waves, modulated together to combine and interact to form very complex wave forms and hence quite rich sounds. However, one of its downfalls was that the sounds could lack a certain richness that was found on analogue and certain other types of sounds synthesis.

The DX7 used six operators which gave the programmer some room to manoeuvre because the more operators you use for creating sound, the richer the sound. The FB01 and all the other synths from Yamaha used four operators. One way round the problem would be to have one of the operators capable of generating other wave forms besides sine. This would give a much wider variety to the sounds created from even only four operators. This is exactly what happened with the TX81Z and its subsequent keyboard follow-up, the touch sensitive DX11. Not only has it those attributes but Yamaha also followed an idea through from the FB01 and the DX21 and put in Performance Memories: that is user-selected and set combinations of voices that are tailored for individual needs — split or layered sounds plus chorus and detune effects with set pitch bend and MIDI peripherals all set up.

This is a very basic outline of the TX81Z which has 32 internal voices in banks, A, B, C, D plus 32 performance memories. It will also accept DX100 voices via the cassette dump and load interface, as well as the usual MIDI dump facilities. It is, of course, touch and after-touch responsive and has a fine set of voices with it when purchased; thanks to the aforementioned different wave forms, the voices are much richer in character and timbre.

Since the TX81Z has now been around long enough for shops to offer discounts and the secondhand market to build up, there has been a growing need for voice programming software for it. The cost should be about £375 new and approximately £250 secondhand.


Many of your letters mention the fact that you have got or are thinking of getting one of these tone modules to add to your setup. A TX81Z plus a touch sensitive keyboard would indeed be a good deal. However, I would recommend that if you were thinking of buying them separately you might consider giving the keyboard version, the DX11, a look over as it comes complete with touch sensitive keyboard and can also be programmed from TX81Z software as well as accepting the DX100 voices.

This fact has not escaped our friends down at Quasar, neither has it passed Martin White — he of the FB01 and DX21 programs — who popped into the Motel recently. I will avoid making a tit-for-tat comparison as they are not always straightforward. However, I would point out that Quasar are prepared to make their program run on any interface and disk drive, and Martin’s is specifically designed for the XRI interface.

‘It’s a great advantage to have all the graphs displayed onscreen’

The Quasar program follows the same format as their other programs. There is one main screen in which all the peripherals of the sounds are displayed. They are graphically shown in either bar or line graph form. Each area is made active by moving a yellow cursor around the screen till it rests on the specific area you want. It’s a great advantage to have all the graphs displayed on one screen, you can see what each operator is doing. Many of the 16-bit well-expensive programs do not have this feature: you are forced to flip from operator to operator, although you might get a dotted line tracer of what is happening with the other operators it is certainly not as efficient as this screen design. Indeed the only problem is that, unlike the super expensive programs, you can’t pull the graphs around with a cursor or mouse. That aside, it is very easy to work with and at £9.95 it’s a bargain. It has the library and bank facilities found on the other voicing programs and this means that you can send to and from the module in either single or bank mode. You can also load up to 128 voices into the library and pick them out for editing, or pull a single voice from the synth directly to the editing page. All these are accessed with a rotating tumbler effect that appears at the bottom of the screen.

Martin White’s program uses a similar format to his other programs in that all the parameters are displayed in numerical form on the screen in lists. Scoot the cursor around the screen and increase or decrease each peripheral at will. This will set you back £24.99 and I have to say that it could do with more graphics to make the program a little more user-friendly.

Nevertheless it’s a very efficient program. I’m sure that it won’t be the last of voicing programs for the TX81Z by any means.


By a happy coincidence, here is a guest who has a TX81Z and a Music Machine. Roger Mephan is desperate to try and write a simple editing package for the two and wants to know how to go about sending MIDI codes from the Music Machine to the module and back again. For real inside dope on the ports used on the Music Machine you’d best contact the Ramm User Club, but my own thoughts are that for the outlay on the Quasar program you might save yourself a fair amount of hassle and also give yourself a flying start. The specific MIDI codes are given in the TX81Z user manual and if you really want to get into MIDI then either prowl around the music section of your local library or hit the music shop with reasonable requests for literature on MIDI — books on this topic have become quite an industry in themselves.

Roger is also annoyed that he can’t hook up his Casio MIDI Guitar with the tone module AND the Music Machine to get both sequences and real-time performance playing merrily away.

Well, it should work via the THRU port of the Music Machine but if this does not work then try one of the inexpensive MIDI splitters from Philip Rees, mentioned many times before in these pages. He extols the virtues of his DG20 guitar and recommends the setup to all and sundry. Finally, Roger would like some device that would give him pitch change somewhere along the line plus other control commands. There are two solutions. Firstly, you get a mother keyboard (assuming you have at least a one-fingered keyboard technique) that will do this for you, as in the larger ones from Cheetah, or you look out for a Yamaha MEP4 MIDI workstation device that will set you back just under £200 and will perform all these tricks for you.

‘A couple of lengthy pitch bends and several K of memory are chewed up’


It would be possible to code it as an additional program on top of the Music Machine’s but I fear you may well use up memory area that is needed for the samples. The alternative is to purchase one of the dedicated sequencer packages for the Music Machine and insert the patch changes in the sequencing routine, though this won’t help with the bending. I would try and avoid putting pitch bend into the sequence itself, as it is very greedy with memory space — a couple of lengthy pitch bends and several K of memory are chewed up. Leave the bending for real time, I think.

However you would need to have some method of placing the MEP4 bend wheel close to hand for using it along with the Casio.

Matt Burke has added to the simple sound sampler program listed in Issue 55. After sampling your sound, if you then enter into the program listing: SAVE "SAMPLE" CODE 65408, 65535 - 65408 and then save the file to tape you can use the sound saved in your own programs. Call it back in by typing: RANDOMIZE USR 65408

Before I go and tidy up the cabins, please accept apologies if mother and myself have not replied to all your letters. Sometimes there just aren’t enough hours in the day! And unless you would like to dive into the bottom of the swamp to retrieve your cassette then include an SAE so that all cassettes can be dutifully returned. More replies and reviews next month. Till then keep the letters flooding in to Batesy, The Bates Motel, CRASH.