The Classic Yamaha DX Synths: A 1980s Revolution

Bob Leggitt | Sunday 27 July 2014
Yamaha DX9 Synthesizer

In the history of popular music, there’s never really been anything else like FM. Frequency Modulation, brought to the mass market by Yamaha through the first half of the 1980s and culminating in the monstrously successful DX range, wasn’t just a new method of synthesis. It was a revolution, changing the synthesizer’s role in music. Formerly, the synthesizer had made futuristic noises and generally performed as an instrument in its own right. It sounded good, but it suffered from limited versatility, and it struggled to slot into a lot of musical genres.

But the Yamaha DX keyboards and TX modules of the early to mid 1980s could convincingly impersonate and replace other instruments, and accordingly, they were the first mass market synthesizers to be viable for use in most styles of music. Whilst the sounds output by the FM synths were not 100% indistinguishable from the real instruments they mimicked, they could replicate the FEEL of real instruments, and that made them compatible with the same roles.

On stages and in studios around the world, FM instruments weren’t just the synth of choice – they’d also become the organ of choice, the electric piano of choice, the accordion of choice, even the bass or harmonica of choice… They weren’t just in command of the synth market – they were in command of the whole keyboard market, and more besides.

Musical genres which had never been associated with synthesizers before, adopted FM, and in particular the DX7, en masse. FM synths were even turning up on broadcasts as conservative as Songs of Praise, and by 1987 their ubiquity in the pop charts was staggering. But one of their biggest, if perhaps most forgotten impacts on music, was their almost wholesale takeover of the TV themes and jingles industry.

If you listened to UK TV advertisements and theme tunes before the FM synths arrived, you’d hear real instruments. Costly productions often featuring a wide array of session players. But the ability of FM synthesis to closely approximate real instruments rendered that unnecessary in the eyes of the cost-conscious programme/ad makers, and FM keyboards and modules began to replace entire bands. It was bad for musicians and arguably bad for music, but it did demonstrate the extent of the FM revolution. Instruments had changed music before, but not even electric guitars had made previous creative processes redundant on that scale.

Flexidisc which accompanied Howard Massey's guide The Complete DX7
The Complete DX7 - Howard Massey's programming guide to Yamaha's product of the decade - not only made an old telephone directory look lightweight; it also came with six sides of audio examples on disc. FM was serious, serious business.


The FMs were also the first commercial digital synths, and their system of sound creation literally turned synthesis on its head. Whereas analogue synths had started the sound creation process with complex waveforms and then allowed the user to filter out the harmonics to taste, the original FM synths started with the most simple wave of all – the sine – and then modulated its shape with another wave in order to add harmonics to it. The FM system could even stack levels of modulation so that an already modulated waveform could be modulated again, with various pitches and levels of modulating wave. The complexity and character of harmonics this could build was in a different league from the possibilities offered by pre-formed analogue waves.

The potential for complex waveforms gave FM synths one of their most valuable properties: their definition and ability to sit well in a mix. Analogue synths had only a measured degree of success in this respect. They were fine when used with other synths in electronic music, or when used for piercing lead breaks or arpeggios, and perhaps the odd ‘pad’, but they struggled to find finesse and could be hard to integrate with some other instruments.

When you played an FM synth stand-alone, it would often sound thin or quite feeble by comparison with a Moog or a Roland. But start multitracking parts with it, and it really came into its own. It wouldn’t invade or 'dirge' out the track. The sounds would slot into their own territory, and because they had such clarity, it was possible to be a lot more intricate in terms of playing than with an analogue machine. A busy mix with an FM synth would often work very well. That had been much harder to pull off with analogue synth sounds.


The FM synths were also players’ instruments. They took synthesis off the path of one-finger blooping, and into the realm of musicianship. Of course, anyone who remembers ELP, Genesis, Yes, The Stranglers et al, will remind us that some ‘70s analogue players were extremely good musicians. But Keith Emerson, Tony Banks, Rick Wakeman and Dave Greenfield were among the exceptions who’d embraced analogue synths as virtuoso instruments. One or two early ‘80s analogue synth players (such as Howard Jones) had also stood out as good musicians before digital synths took hold of the market, but in general, the trend with synths prior to FM had been for very basic or mechanical use. Interestingly, some of the more impressive and forward-thinking analogue synth players, including Howard Jones, quickly adopted FM.


But FM’s grip on music as a whole was not immediate. It wasn’t like the DX7 and DX9 hit the market in ’83 and by the end of the year the entire business was awash with their sounds. At Christmas ’83 supply could still not, in any case, meet demand, so even those who wanted to use DX7s in some cases couldn’t get them. 1984 did see the DX7 infiltrating the higher echelons of pop and rock though, and FM synths were in use in indie and even punk music by 1985. But the real saturation point was not reached until the second half of the ‘80s.

At amateur levels, the final leg of the saturation came through 1986, when Yamaha broadened its range of DX keyboards to accommodate a wide raft of budget points, from as little as £349. As a result, the DX instruments dominated virtually every placing in the bestsellers chart. You couldn’t pass the window of a musical instrument shop without being bombarded with Yamaha’s dark brown and teal/green livery. Even shops whose window displays had previously only comprised guitars, brass and the odd organ, were awash with DXs.

Yamaha DX7 by rockheim, on Flickr
Image by rockheim, on Flickr. Modified under terms of Creative Commons licence. Image cropped, black background added, colour temperature modified, and general enhancements performed.


Yamaha’s ‘golden era’ DX keyboards, introduced between 1983 and 1986, divided into three basic groups, split according to the number of sound creation operators the synths featured. An operator was simply a sine wave, which could be used interactively with the other sine waves available in the instrument, to produce patches. The more sine waves available, the more powerful the synth. The DX7 stood alone as the only model with a single 6-operator engine. Beneath the DX7 there were the significantly less powerful and capable 4-operator models, and above it there were the much more expensive 12-operator models, which were more accurately 2x6-operator models, comprising dual DX7 units under a single bonnet.

The 6-operator DX7 became the legend because it was the definitive implementation of the technology and its price point, whilst not in budget territory, was still widely inclusive. 4-op synths were a compromise. 2x6-op synths were out of most musicians’ financial reach, and since they just combined two instances of the DX7 system, they were not really a system in their own right. Anyway, here’s the range in brief…


A big, horrendously expensive and pro-build-quality precursor to the DX5. Appeared in 1982 as the Yamaha CSDX – the prototype FM synthesizer, but was eventually released to market in slightly modded form as the DX1 in 1984. Externally, it doesn’t look in keeping with the original DX range (it’s more like a late ‘70s synth in appearance), but internally it’s basically a pair of DX7s coupled in one unit.


Like the DX1, 1985’s DX5 contained two DX7-type 6-operator tone production modules, but was packaged in a much more familiar casing, which echoed that of the landmark DX7. The DX5 was less than a third of the price of the DX1. Unlike the DX7 it had a weighted action keyboard.


The definitive FM synth. A single 6-operator tone engine, no built-in effects, monotimbral, and a set of original presets that stunned musicians and changed the world of music. Went to market in 1983 after long delays, and despite the DX9's better availability in the early days, is regarded as the first mass market FM Synth. It was also the first synth to truly unify both the amateur and professional markets.


The only other FM keyboard synth Yamaha released in the launch year of 1983. The DX9 was Yamaha’s original 4-operator product. Again, no effects. You got the bare bones and that was all. The ‘missing’ two operators made a big difference to the substance of the sounds the DX9 could create as compared with the DX7. Unlike later 4-op synths, the DX9 was pricey, originally going to market with a four digit RRP. It didn’t have the DX7’s velocity sensitivity, and it was also compromised in terms of patch storage, holding just 20 presets at any one time, and not featuring any ROM augmentation like its 6-op sister. New DX9 presets were loaded from tape, which was obviously impractical during a gig, so performances were confined to 20 patches.

BUT, in my opinion, the DX9’s presets were much better programmed than those on the cheaper 4-op synths of 1986. Most of the later 4-op presets sounded like they’d been bashed in under severe time pressure. The DX9’s frontline patches, conversely, were as well programmed as the DX7’s. They couldn’t be as strong because the 6-op architecture wasn’t there, but whoever programmed them knew how to make the most of a 4-op synth. The DX9 also had double the polyphony of later 4-op FMs, and it should be noted that whilst the ‘9 only stored 20 patches, it originally came with a tape containing no fewer than 420!


One of a new, three-strong range of 4-operator FM synths to appear in 1986 and virtually starve out other synth manufacturers with new price points and unprecedented value in digital keyboards. The new trio of 4-op DXs (which superseded the DX9) took places one, two and three in the UK bestsellers chart that summer. The DX21 was the best of the new trio and was the number one bestseller. It bettered its two new 4-operator stablemates in its inclusion of an onboard chorus, plus 2-part multitimbrality and true key-splitting. The DX21 also featured better MIDI spec than the earlier DX7 and DX9. However, I’d still choose a DX9 over a DX21 or any other 4-op FM synth from 1986, because of the ‘9’s factory presets – which couldn’t be loaded into the new 4-op range.


Also in the 1986 trio, the DX27 was a basic, no-frills, 4-operator synth similar in nature to the DX9, but this time priced to sell, and with plenty of onboard patch storage space. The DX27 cost just £475, which was way under half what the DX9 had originally cost. Prices on lingering DX9s were slashed to the same ballpark as this synth after it hit the shops.


Same gubbins as the DX27 but in a much smaller case with mini keys and a much lower price. At £349 the DX100 was easily the cheapest of the original Yamaha DX keyboards.

Magazine ad for the Yamaha DX7II
Original UK Yamaha DX7II-D advert, from 1987.

POST 1986

As 1986 drew to a close, there was a sense that the DX range may have tainted its own appeal through over-saturation of the market. The original DX7 was now also out of date in terms of its very basic MIDI spec, and Yamaha would have known that the market would not tolerate the 1983 keyboard’s hissy output and compromised, 14-bit top end for much longer going forward.

This resulted in the birth of an updated series of DX7 models: the DX7II-D, the DX7II-FD, and the DX7S. Whilst the DX7II models were technically very clear superiors to the original version, I felt that Yamaha failed to convey their advantages effectively to potential buyers. And once Roland’s LA synthesis stormed the market shortly after the DX7II hit the shops, the DX7II range was always going to be short-lived.

By then, original DX7 prices had crashed on the secondhand market, and the DX7II was not considered distinct enough an improvement to warrant paying nearly three times the price of a S/H original. The standard DX7II-D had a UK list price of £1,700, which was just too expensive given that the old DX7 had been discontinued at an official RRP of £1350, with many dealers prepared to come down to £1,100. The new Roland D50’s price of £1,450 (for cutting edge technology) showed what a big mistake Yamaha had made with the DX7II. They needed it to be both better and cheaper than the old DX7.

The DX7S addressed this to an extent, with just the basic updates on the DX7 design for a more modest price. But again, the marketing wasn’t very good, and the ‘S was perceived as some kind of pariah version for cheapskates who couldn’t afford the ‘proper’ model. The DX7S was even dubbed the DX3½ in the music press – only in humour, but stuff like that can damage perceptions horrendously. Contrary to what some people believe, it did sell very well indeed up to mid 1988, but part of that was because shops tended to discount very heavily on its RRP, and its success was admittedly short-lived.

The swansong for the original DX synths came with the DX11, which went on sale at the start of 1988. It was only a 4-operator model, but was technically more powerful than previous 4-op FMs because its raw, unmodulated waveforms were not limited to simple sines. It was also packed with features and it managed to hit the magic price point which had brought the DX21 so much success. The DX11 remained competitive against the Roland D50 (and was the only Yamaha DX to do so). In fact, by late summer 1988 the DX11 had subordinated the D50 in the UK sales charts, and was only outsold by Roland’s scaled down LA synth, the D10. By then, though, the Korg M1 was on the rise, and the DXs were effectively over as a retail phenomenon. By spring ’89 there were no Yamaha DX synths at all among the top ten UK sellers. The most remarkable commercial spectacle in synth history had finally come to an end.

Garage clear out - somewhat dusty Yamaha by garyturner, on Flickr
Image by garyturner, on Flickr.


Most of the criticisms of the original FM synthesizers have sprung up in retrospect. In their day, the biggest complaint was the difficulty in programming them, which was a stark and obvious headache after analogue synths with simple real time controls on the front panel. There was a desire to program the DX synths, which resulted in costly, third party instruction books weighing almost as much as the actual keyboards (well, heading in that direction, anyway). But the beauty of the range was that there was already plenty of sonic variety in the factory presets. I highlighted the brilliance and importance of the presets in my DX7 article. That so many of the DX7 sounds appearing on commercial records, on professional stages and in TV music were only simple tweaks of the original presets, was a testament to the usability of the synth as is.

Other gripes such as the 14-bit sound and the general lack of ‘balls’ from FM synths were of little consequence in the mid ‘80s. Keyboardists had had instruments with ‘balls’ all through the ‘70s and early ‘80s and they were bored with that. What they wanted in the 1984 to 1986 period was refinement, clarity, sophistication. And without the reference point of 16-bit sound conversion, the quality of 14-bit seemed fine.

The same, of course, goes for the earlier DX keyboards’ monotimbrality. No one knew what multitimbrality was in the middle of the ‘80s, let alone cared about it. The fact that you can only get 1 part out of an original DX7 only became a problem after the shelf life of the instrument. Indeed, part of the reason the DX7II-D never duplicated the original's success was that even in 1987, too few people really 'got' the implications of its extra layer of timbrality.

The 4-operator synths were open to a lot more criticism than the 6-op DX7, because side by side, in a shop, their preset banks were inferior by comparison. Trying to make DX7 sounds on a 4-operator synth was like trying to complete a jigsaw with a third of the pieces missing. You just couldn’t do it.


Yamaha’s DX range created a stir in the keyboard world like nothing before or since. You can cite all sorts of reasons why they did so well… Bringing digital synthesis and its peripheral benefits to the player in the street, closely simulating real instruments for the first time, hitting budget levels that no truly happening keyboard had ever hit before… Even appealing visually with a slick and attractive look…

But what probably propelled the FM synths the furthest was their usability. They weren’t full of sounds that raised exclamations of “OMG!” in the shop but were basically useless when it came to creating a track. The FM synths were unassuming and unspectacular in the one-finger demo test, but then, so was a Bosendorfer piano. Like all the greatest keyboard instruments, Yamaha’s DX synthesizers were built and programmed for practical use, and they came into their own when it mattered – not when it didn’t.