Trackers vs MIDI, part deux

The previous post got rather long(winded) already. But shortly after I posted it, I realized that I had not yet said all that I wanted to say. Namely, I mentioned the Yamaha FM synthesizer chips at the start, and I wanted to get back to them later, when discussing trackers. However, I solely focused on sample-based trackers and the UltraSound there. So this time, let’s look at trackers for other types of synthesizers.

It mostly revolves around what I briefly mentioned before:

But I just said that I thought the Sound Blaster Pro 2.0 sounded bland. What happened here? Well, my guess is that MIDI happened.

What is the most ‘characteristic’ thing about synthesizers and synthesizer music in general? I would say that it is the fact that synthesizers generate the sound in realtime, and you can modify the parameters of the generated sound in realtime. A common effect is the ‘filter sweep’, where you change the sound from a bright sound moving to a dark sound and back. You can listen to music from Jean-Michel Jarre for many examples of that. His sounds are constantly ‘morphing’:

You will find plenty of such examples in music on the Commodore 64 as well, since the SID chip is also a ‘subtractive’ synthesizer like these early synths from the 70s and 80s, which first generates a basic waveform with an oscillator, and then runs it through a filter with cutoff and resonance parameters to shape the final tone. This is one of the defining features of the SID chip: its contemporaries lacked the filter. Another ‘synth’ feature it has is ring-modulation. A third feature is that you can adjust the duty-cycle of the pulse wave, to control its timbre. Using these features and manipulating their parameters allowed the SID to sound far more ‘synth-music’-like than any other computer at the time:

Now, Yamaha was of course also a big name in the synthesizer-world of the early 80s, most notably with the DX7. The DX7 introduced the world to FM synthesis. Purists will say that no filters are used in FM synthesis, and unlike the SID and other early synthesizers, which work with analog signals, FM is actually implemented mostly as digital algorithms, with only an A/D converter at the end of a chain.

However, in practice, the concept is much the same: the sound is generated in realtime, and you can adjust parameters in realtime as well, for various effects. Even on an FM synthesizer you can get quite convincing realtime controlled filter-like sounds, very ‘synth-like’:

This brings us back to the world of PC soundcards, as the popular AdLib and Sound Blaster cards also used FM synthesizer chips from Yamaha, namely the OPL2 and OPL3 as mentioned before.

While these chips may not be as advanced as a real DX7 synthesizer, the basic concept still holds: the sound is generated in realtime, and various parameters can be tweaked to modify the sound in realtime, creating a number of effects. The problem here is that each synthesizer has its own unique sound generation engine, with its own unique parameters to tweak in realtime.

MIDI allows you to tweak these parameters, but the problem is that there are only a handful of standardized messages defined in MIDI:

  • Note on/off (with velocity)
  • Aftertouch (with velocity)
  • Pitch bend change

These messages allow you to start or stop a note, to set the volume and pitch, and that’s basically it.

Anything else is done via generic messages for ‘control change’, ‘program change’ or with System Exclusive (SysEx) messages. The problem is: there is no standard for how these MIDI messages should map to the synthesizer. Or well, SysEx messages are well-defined, but only for a specific synthesizer, so you need customized software to support it.

And that is more or less the clash between MIDI and PC sound cards: MIDI is trying to be a very generic solution for recording and replaying musical data. It works well when you have a dedicated synthesizer hooked up, and any realtime changes you make on the synthesizer are sent as MIDI messages, which can be recorded and replayed by a MIDI sequencer.

The problem with the AdLib and Sound Blaster cards was that such a ‘development station’ didn’t really exist: the cards did not natively support MIDI, and there was no synthesizer to easily generate MIDI commands for all sorts of parameter changes. So if you wanted to go the MIDI route, you’d first need to write your own MIDI interpreter to drive the OPL chip, and then set up a MIDI controller and sequencer to control the OPL chip and compose music for it.

It seems that there is somewhat of a disconnect between the two worlds here. You would have musicians who were at home with MIDI, but who weren’t programmers themselves, and could not make a MIDI interpreter for the OPL chip. And then there were programmers who would be able to make a MIDI interpreter. But they would rather choose a more straightforward tracker-like solution. This led to MIDI mostly being used with simple standard MIDI drivers, with generic instrument presets and no realtime control of any synth parameters.

However, a few brave souls did in fact build trackers for the OPL chips. And they did actually play around with the instruments and showed off what the OPL chip was really capable of. One such tracker is EdLib, made by JCH. You might vaguely remember that name, since I also used a tune composed in EdLib in the 1991 Donut.

What is interesting is that JCH converted some C64 songs to EdLib. Listen to The Alibi by Laxity, first the original:

And then the EdLib version:

As you can hear, the C64 version modifies the sounds in realtime, and this AdLib tune does pretty much the same. What I like about the conversion is that it does not sound like JCH wanted to make the AdLib-version as close as possible to the C64 version. But rather, he tried to really adapt it to the AdLib and make it sound as good as possible on the OPL chip. The result is possibly one of the best AdLib tunes ever made, and certainly way better than the generic MIDI sound that is usually associated with the AdLib.

Another nice example is the soundtrack from the game Dune:

My favourite track is probably ‘Water’. It really shows off the metallic percussion sounds that FM can do so well. It makes it sound very bright and fresh, way different from the ‘muffled’ sounds of most 8-bit sound chips.

The Dune music was made with the HERAD system, which was loosely based on MIDI, but specifically targets the AdLib, so it is probably closest to the custom MIDI solution I meant above. The Dune-music is a great demonstration of what HERAD can do with an AdLib in capable hands.

Lastly, I also want to mention the game Tyrian. This one also really stood out on the AdLib back in the day:

Again, this game uses its own custom software for AdLib, known as Loudness Sound System (LDS).

 

Some more examples of outstanding AdLib tunes can be found here on the Crossfire Designs site. I also discovered the obscure ‘Easy AdLib’ tracker there, which also includes some very nice AdLib music:

So the story of FM synthesis on the PC is generally a sad one, with but a few highlights. If you knew how to program it, you could get some fantastic sounds from it. But it was not an easy chip to program. As a result, it seems that most game developers were just happy to get any sound from it at all. For a card that has been the standard in PC audio for such a long time, remarkably little software for composing music on it has been released. I suppose most game developers neither had the tools nor the skills to really make the AdLib shine.

Which is a shame, since FM chips were also used in quite a few arcade machines, consoles and home computers, mostly Japanese. And there’s lots of great FM music out there on chips that are quite similar to the OPL2 and OPL3 used on PC sound cards.

So I would like to close today’s blog with a recent demo from Titan for the Sega Mega Drive. The Mega Drive uses two sound chips, one being the SN76489 which we also know from PCjr and Tandy. The other being a Yamaha YM2612, an FM synthesizer.

 

 

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4 Responses to Trackers vs MIDI, part deux

  1. Nice post. Dune is a work of art, both music and graphics. The soundtracks really show what even a simple FM synth (compared to a DX7, for example) is a capable of.

    If we want to be accurate (or pedantic) we’ll say that FM is neither subtractive nor additive synthesis. There are certainly no filters, but changing the parameters can change the sound in a way similar to what filters do. Completely different underlying mechanisms, similar results.

    The OPL2/OPL3 are both 100% digital chips, no question about it. Without a DAC it’s just bits. It’s in theory doable to do analog FM but I don’t think anyone managed to do it reliably before digital FM took over. And FM has been digital since the 1970s when Chowning/Yamaha worked on turning it into a product, AFAIK they never even tried to build analog FM synths.

    You could probably say that the AdLib/OPL2/OPL3 was a victim of circumstance. It’s a nice little synth chip, but the “market” (game developers) wanted more traditional music. It probably didn’t help that every platform had different sound generation capabilities, hence a search for lowest common denominator. Basically the OPL FM synths ended up being forced to do something they weren’t great at, and then got a bad reputation for not faithfully reproducing a piano or a guitar.

    On a purely practical level I wonder how many people there were at the time who were able to compose “traditional” music vs. synthesists who were able to create their own sound and compose synth-oriented music.

    I’m slightly surprised that I don’t see AT2 (Adlib Tracker II) mentioned, given that that’s an OPL tracker still updated to this day.

    • Scali says:

      It’s in theory doable to do analog FM but I don’t think anyone managed to do it reliably before digital FM took over.

      Yes, even for the ‘simpler’ subtractive synths, there were already problems with analog circuits. You had problems with noise/crosstalk, and also problems in keeping the oscillators in tune.
      In an FM synth, these problems would only be multiplied, quite literally.

      It’s a nice little synth chip, but the “market” (game developers) wanted more traditional music.

      Do you think that is true for the PC gaming market? I don’t think it is for game consoles or home computers. Eg, the C64 examples I posted don’t exactly sound ‘traditional’. The composers really seemed to treat the SID chip as an instrument in itself, and just wanted to make the best possible music within its limitations. The SID is even more limited than the OPL2 when it comes to trying to mimic guitars, pianos and such.

      On the other hand… perhaps because on the PC market there were also high-end solutions like the MT-32, which indeed was capable of more traditional music, and the OPL2 being more high-end than eg the SID, that composers tried to go into that direction more. Perhaps a bridge too far for the OPL2 though.

      On a purely practical level I wonder how many people there were at the time who were able to compose “traditional” music vs. synthesists who were able to create their own sound and compose synth-oriented music.

      Yes, that is something I didn’t really get into…
      It’s not easy to program FM sounds. I suppose the same goes for the SID. Getting a good sound out of it is one thing. Getting a number of good sounds out of it, which also fit together nicely, and work for a song, I suppose that takes a very specific type of composer. Mind you, in the 80s, there was an abundance of synth-powered pop bands, so it was probably considerably easier to find such composers back then than it is today. On the other hand, some of these people just used the Yamaha DX7 presets.

      I’m slightly surprised that I don’t see AT2 (Adlib Tracker II) mentioned, given that that’s an OPL tracker still updated to this day.

      Well, that’s mainly because I’m not familiar with that one 🙂
      I thought it was 386+ only, but on the website it seems there is at least an old 16-bit version. I wonder if it works on 8088 (the reason I used EdLib at the time was because it was the only one I could get working on 8088/286).
      My personal tracking experience is quite limited, I’ve mainly used ProTracker and FastTracker II back in the day. But I got more interested in programming, mostly graphics, so I never became all that good at tracking myself, and haven’t done it in ages.
      I did have a Yamaha YS-100 synthesizer for which I programmed/edited some sounds. I used that in combination with an Atari ST1040STe and Cubase.
      In fact, some of my music from that era, with the YS-100 is still online:
      http://www.soundclick.com/bands/page_songInfo.cfm?bandID=436524&songID=3102180
      http://www.soundclick.com/bands/page_songInfo.cfm?bandID=436524&songID=3102216
      http://www.soundclick.com/bands/page_songInfo.cfm?bandID=436524&songID=3102257

  2. Heh, multiplied problems indeed 🙂 Yes, that’s exactly why analog FM didn’t make it. And although I have no direct experience, I understand that analog synths only became truly usable when they went halfway digital (remembering presets, not going out of tune with temperature changes, etc.).

    Yes, I think the demand for “traditional” music was true in the PC market. In other markets (C64, consoles) less so. On the PC, the MT-32 and later Sound Canvas were considered to be the gold standard (right or wrong) and OPL2/3 had a lot of trouble keeping up with those.

    I’d say that basically on a platform where OPL (or SID, or whatever) was the only thing there was, people got the best out of it. But on the PC it was always only one of the options, and there was an irresistible push towards trying to emulate the “high-end” devices, which often just made AdLib sound bad. Kinda like the EGA versions of VGA games usually looked like crap, even though EGA really was not that bad.

    Everything I’ve read about FM suggests that it’s a powerful synthesis technique but it’s not intuitive, and it’s difficult if not impossible to learn how to make new sounds in some kind of a directed and predictable fashion. Great for experimenters, not so good for everyone else. I think that’s why for example Alistair Sanger (The Fat Man) was so successful in licensing his FM instrument patches to everyone, because it was really hard to put something like that together.

    Nice tunes BTW!

    • Scali says:

      Yes, I think the demand for “traditional” music was true in the PC market. In other markets (C64, consoles) less so. On the PC, the MT-32 and later Sound Canvas were considered to be the gold standard (right or wrong) and OPL2/3 had a lot of trouble keeping up with those.

      Yea, I suppose the different sound devices should be treated as different ‘platforms’… That is, many games were ported to a number of platforms. In the late 80s to early 90s, the same game would often be available on C64, Amiga, Atari ST, and PC, and sometimes also on other platforms, such as ZX Spectrum, Amstrad CPC, (S)NES, Sega etc…

      The music and sound-effects would often be custom-designed/optimized for each platform. Often the different platforms would be done by different developers. And in some case the music was even completely different.
      If they had taken this approach for the different audio devices on PC as well, who knows what could have happened. But I suppose that would make the PC version a whole lot more expensive.
      The same probably goes for graphics: redoing the graphics to optimize them for all the different standards would make the development way more expensive than just using some color reduction tool on the VGA graphics.

      Everything I’ve read about FM suggests that it’s a powerful synthesis technique but it’s not intuitive, and it’s difficult if not impossible to learn how to make new sounds in some kind of a directed and predictable fashion. Great for experimenters, not so good for everyone else.

      Oh yea, that Yamaha YS-100 I had was a 4-operator FM synth, much like the OPL3 or the IBM Music Feature Card.
      And all you had was a few small buttons and a two-line LCD screen. So the user-interface was quite horrible. You basically just saw a bunch of ‘magic’ numbers, which you could increase or decrease, and some other options to toggle.
      It was very unintuitive indeed, very difficult to predict how different settings would change the sound, let alone how to mimic a certain sound you have in your head.
      So I basically just used trial-and-error: I would just go through all sorts of options and listen to how it was changing. Basically I would just experiment until I found some sounds that I liked, and let the sounds inspire me to write some music to use it with.
      In other cases, where eg I wanted a ‘piano’ or such, I would just start from a preset, and perhaps just tweak it a bit.
      So it’s not like I knew exactly what I was doing, but it gave some interesting results nonetheless 🙂

      Nice tunes BTW!

      Thanks, they’re really old… late 90s I suppose, so around 20 years old by now. The later stuff sounds better, luckily… but these are the only tracks that use the FM synthesizer, I believe.
      The keyboard broke down at some point (it was already a relatively old synth when I got it, second-hand), and I just threw it out. These days I use a Roland Juno-D, so no more FM.

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