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Atari and the DX7


[Photo: Yamaha DX7]

The advent of the DX7
It was 1983. Yamaha revealed the milestone synthesizer, the DX7. One of the unique contributions in this keyboard was that it was one of the first synths to have MIDI (Musical Instrument Digital Interface). All sorts of cottage businesses grew up in the wake of this synthesizer, offering sounds, software and hardware add-ons. Atari was just starting to make its name in the music industry. Many software firms quickly made editors and librarians for the Atari platform that would support the DX7. Steinberg as well as C-Lab, Hybrid Arts and Dr T's Software all produced excellent editors and librarians dedicated to the DX7 and its 4-operator cousins (the TX81Z, the DX100 and DX11). Not only that, but thousands of sounds became available by third party contributors. Also, programs were developed that encompassed not only the DX7, but multiple synthesizers all in one program. Dr T's XOR, Hybrid Art's GenEdit and Sound Quest's MIDI Quest are some examples. This was a great time for MIDI as new ways were being explored and new synthesis structures were being created.

Some theory
The DX7 and family use what is called FM (Frequency Modulation) as its main sound structure. FM (as used in the Yamaha DX series) was developed at Stanford University by a certain John Chowning. Basically (in a real small nutshell) FM uses as its main sound source what is called an "operator". An operator consists of an oscillator (a sine wave) and an 8-stage envelope generator. These operators can be arranged in many ways. The different ways they can be arranged is called an algorithm. When you see the terms 6-Op and 4-Op, this means how many operators you have to work with. There are basically two ways you can arrange operators. Either an operator is a carrier (it makes the sound) or a modulator (meaning it affects the sound of the carrier, such as how bright or tinny it is). The envelope in a carrier will affect volume, while an envelope in a modulator will effect timbre. This can be rather confusing, but is very easy once you "get it". There are excellent resources on FM theory on the internet worth delving into as well as books. A recommended book is Howard Masseys', "The Complete DX7". See the link section for a good resource on FM theory.

2002: the present
Today, even after Yamaha has stopped production, the DX7 family is still here. Awakened by a strong internet community, there are many resources for the DX7 which makes obtaining one, or its other flavors of FM synthesis a very reasonable and rewarding experience. Modern modules using FM technology have also been made available by Yamaha: the FS1R and the AN200/DX200. There are also soft synth alternatives for PC which create 6-operator synthesis in software. You can even load DX7 SysEx banks into them. You could even say that FM is making a come-back, much in the same manner as analog has come back into the mainstream.

Another factor is that you can now obtain these FM goodies very cheaply. What used to cost $1,700 (and non-discounted for the first year it was out) you can now obtain (DX7 Mark I, or even a Mark II) for about $200 to $300. TX7s (the desktop version of the DX7) you can get for $75! The FB01 4-Op module for around $40! The TX81Z (with its landmark techno sound "lately bass") can also be obtained for less than $100. These instruments are so reasonable that it would be foolish not to get one for the studio.

Once you obtain one (or more) of these jewels, it really needs to be used with an effects unit. A good reverb, delay and chorus goes a long way in bringing out the sounds what others would call "cheesy". You will be amazed at how good these instruments can sound when a good reverb or chorus is added. A must for anyone who plans on using a DX!

[Screen-shot: Dr T's XOR]

Enter Atari
If you have an Atari, there are now many editors, librarians, sounds and utilities for 6-operator and 4-operator instruments that will keep you going for as long as you have the instrument. This is due to the programmers giving their consent to release their programs as freeware as well as PD applications being made available. However, there are still some programs not available (yet) such as C-Lab's X-alyzer and Steinberg's Synthworks DX7 editor. Both of these offered excellent graphics and features. There is also XOR, which has a DX7 profile as well TX81Z , FB01 and the DX7II profiles.

[Screen-shot: DX Heaven]

DX Heaven
The Caged Artist series of synthesizer System Exclusive (or patch) editors/librarians was created by Bob Melvin and distributed by DR T Software in the late 1980s. Today, Bob Melvin has given permission for free trading of these excellent editors. The first program in the series was "DX Heaven" which was for the first generation Yamaha DX7/TX7 synthesizers. It was, as the title states, for DX7 programming. DX Heaven was originally written in the mid '80s for the Apple II computer but was ported over to the ST with many additions. DX Heaven could also be used as an MPE module for use in Dr T's Omega II KCS. Thus you could play a sequence in KCS, and be tweaking the sound at the same time. DX Heaven also has an excellent random patch generator, making it fascinating to hear what the computer comes up with which can create interesting patches. You can choose which parameters (mask) and what percentage of change you want. Then the more you click on "randomize" it keeps generating new patches, which you can keep or discard. Using one seed patch, I was able to generate many "useable" patches and also create sounds that would have been hard to create "by hand" only because I would not be that extreme in selecting the parameters.

Auditioning sounds is easy using the arrow keys as well as just clicking on a sound. The editing screen shows all parameters at once, which makes seeing the whole patch convenient in making comparisons. There is also a separate envelope graphic screen in which you can drag around points of the envelope with the mouse for some real fast editing of parameters! The interesting thing about this graphic is that you see all operators at once while the one you are working on is highlighted.

The Caged Artist series also included 4-Op Deluxe, the editor and librarian for 4-operator FM synths, such as the TX81Z, FB01, DX11 and DX100. These editors could also be used in conjunction with KCS as MPE modules (as mentioned above). The neat thing about this is that you can have several editors up and running at the same time and simply click in-between them. For example, I have KCS version 4 installed on my Falcon. When I run the KCS program, it automatically loads DX Heaven, the FB01 and TX81Z editors as well as the MT32 editor (which I use as well). By simply going to the MPE menu on the main screen of KCS, I can choose which editor I want to work in. Makes for a very nice multi-tasking musical environment!

[Image: Hybrid Arts' DX-Android]

This was Hybrid Arts contribution programmed by Tom Bajoras. The program was originally named DX-Droid, but had to change its name to appease the force! (George Lucas and friends) So the final version was called DX-Android. There were even adverts in the electronic music magazines at the time with a picture of a droid (very akin to Star Wars) playing a DX7 and ST computer along with a TX816 rack! Those with DX7 synths today can still use this excellent program. DX-Android was one of the first programs to incorporate random patch generation, thus making it a landmark application in its time. In many ways it almost seems like a "DOS" program as it did not use the GEM menu system, but using a combination of function keys, mouse and arrow keys, allows navigation through all the elements of the program. This program also presents many screens to view different aspects of FM synthesis, thus offering a different way to program than the one-screen view. Highly recommended!

Today, Tom Bajoras has released DX-Android and the source code. I have been working in conjunction with David Leaver to produce a copyright-free version. He was finally able to take out the copy protection, so now we have a working edition of this fabulous program. You need to have a formatted disk handy as the program asks for a blank disk when first starting. There is no manual yet, but with the tried and true method of click, enter and learn, you will be able to manage the program, which is logically laid out.

[Screen-shot: DX Bunker]

DX Bunker
Recently, several excellent PD programs have become available. DX Bunker from Germany is no exception. This program can even be run in 030 VGA color modes with good result. DX Bunker offers drag-and-drop functions as well as an editor function with graphic envelopes of each operator, and this all on one screen! It also has a library function, which means you can have more than just 32 sounds. You can store all your sounds in the library, then create custom banks of sounds that you can send to the instrument. There are also different options in viewing the display, as you can invert the color scheme. The menu is in German, but you can easily figure things out. A good collection of sounds come with the program.

[Screen-shot: DXEDIT]

DXEDIT is another more recent PD application coming from Santa Barbara, California's Jim Patchell. This application also works in 030 VGA color modes. It is meant for the Yamaha TX816 rack (which consists of 2-8 DX7s in a rack!). When first opening the program, it asks which MIDI channel, as the TX modules are separated by which MIDI channel you choose. To work on a sound, you first go to the Ed-Op menu and choose an operator. Once you click OK, you can go back to the Ed-Op menu and choose what you want to edit: envelope, scaling, frequency, and sensitivity. These bring down graphic sliders. The envelope graphic is interesting in that instead of the usual x-y bar, you have sliders for the envelope, much in the same fashion as analog synths. Going into the Ed-Mod menu, you can pull down an impressive algorithm list, which makes it very easy to pick the correct algorithm for the job!

All the above programs work on Steem, the Atari emulator for PC. There are even special provisions for SysEx that the programmers of Steem have incorporated into the program. Thus if you do not have a real Atari, you can still use these excellent editors.

DX7 programming tips
I tend to look at DX programming as putting together components to make one sound.

  1. Pick your algorithm. I usually start with algorithm 5 or 6, which gives you three stacks to work with.
  2. Work on one stack. Mute the other operators you are not working on. This is tremendously helpful. For example, using algorithm 5, I want to work on operators 1 and 2. I mute operators 3, 4, 5 and 6. Now you can concentrate on getting a cool sound using operators 1 and 2.
  3. Work the envelope of the first operator. This will form the basis of the sound. Then slowly turn up the operator level for the next one. At this point, you have to decide what type of sound you want. Do you want a bell type of sound? Then you will need a high frequency on operator 2, a fairly low output level so it is not overwhelming and and a sharp attack on the envelope. When you are satisfied with how that sounds, mute operators 1 and 2, unmute 3 and 4, bring up the operator level for operator 4, and then decide what type of sound will go well with your bell sound you just created. Perhaps you want another bell sound, but you can detune them from operator 1, so when you put them together you get a full chorused type of bell sound.
  4. So for each stack: decide what type of sound you want.
  5. When completed, unmute all operators and listen to the result. Add any finishing touches.
  6. Now decide what types of modulation, velocity and keyboard level scaling you need.
  7. When completed: save the patch!

This is one viewpoint on programming. Another is to take an existing patch, and edit it from there to your liking, adding velocity changes, pitch envelope effects, or whatever. One of the unique aspects of the DX7 is that whenever you go into edit mode, you are working on a copy of the patch and not the actual patch. Thus you can be free to tweak to your heart's content knowing you are not messing up the original sound.

Super lead DX
Here is a technique I have learned through the years for getting super lead sounds from the DX:

  1. Use any sustaining patch such as strings, analog brass, organ, whatever.
  2. Put the portatime to 2 (or whatever you want).
  3. Use SUS-key P follow Mode for the portamento.
  4. Step on the sustain pedal, and hold it.
  5. Start playing your riffs.
  6. You will notice the volume going up and it turns into Mono mode, but a very interesting tone that is different than using regular portamento. Really great lead sound! Try it! Beats the pants off some of the stuff you hear these days!

Loading DX sounds
A note on loading the DX7 sounds. Go to function button # 8 (which is labelled on the original DX7 as the MIDI function button!) and set the MIDI channel to 1, and enable System Exclusive. Also turn off Internal Protection. I would back-up your internal sounds also, before dumping new sounds in. Use any of the programs described or a generic MIDI SysEx program such as Midian.

Les MisÚrables
There are also Broadway productions which still make use of the DX7 in their score. "Les MisÚrables" is such a production. As a matter of fact, the original production company issues disks with the DX7 sounds in Atari Steinberg Satellite format. I have been contacted more than once in regard to this and have been able to help these musical directors in converting the sounds to standard SysEx format for use in their production of Les MisÚrables. One of these directors (Neil Booth) wrote up some notes on his experiences of his production of Les MisÚrables. See my DX7 page on TAMW for the story. The production makes use of four DX7s. There are two keyboardists, each with a set of DX7s, pre-programmed with the correct sounds. The score has marks when to change the sound and what patch numbers to call up on which DX being used (upper and lower keyboards). It has been said that this combination of DX sounds gives Les MisÚrables its "sound". A well-deserved compliment to a classic line of synths.

Sounds: DX Convert
"How about sounds? Where can you find sounds in Atari format? Anybody have DX7 sounds in DX Heaven format?"  I hear you say. The answer to both of these is a resounding yes! There are banks of sounds in DX Heaven format, as well as an excellent and much-needed utility created by an Atari MIDI member Ross Maclver called DX-Convert. This application converts Dr T/XOR format files to standard SysEx as well as SysEx to Dr T. This means you can convert those thousands of banks available on the internet and use them in DX Heaven. The same goes for 4-Op Deluxe users as Ross created a utility for that as well!  

To send regular SysEx files, there are dumper programs like Dumpit by Ben Hall, as well as a full-scale SysEx program called Midian. Both of these are available on the DX7 page on TAMW (see below).

User groups

  • Dave Benson's DX7 list
    There are now several user groups on the internet. One of the first and probably the most popular is Dave Benson's DX7 list. You can go to his site to sign up. I have been a member for years and have had the acquaintance of many Atari users there as well. Dave Benson's DX7 site is considered the resource for the DX7, see the links section.
  • FM synthesis Yahoo group
    This one was started by a certain Adam Fandert, whom was also a member of the Atari MIDI forum at Yahoo (in which I am moderator). This forum is good for discussion of all types of FM, and not just Yamaha-style FM.
  • The DX Yahoo group
    This is a large group devoted to the Yamaha style of FM synthesis. Many Dave Benson group members are here as well.

FM to the future
With all these excellent resources now available, now is the time to avail yourself with one or more of these FM jewels. The price is right and the software is free! What can you say? Adding FM to your present set-up will greatly enrich the overall sound as well as giving you an education in a unique form of synthesis. The FM sound when layered with analog or sample technology offers a unique and rich sound not otherwise possible. Another factor is that you will have the largest patch collection ever developed for a single instrument as there are literally thousands of patches available on the internet! Perhaps we will see a well-deserved comeback of these fabulous instruments. Can you see a 100-operator, 300-algorithm machine? Food for thought! 

For more FM Atari programs, please see the DX7 page at Tim's Atari MIDI World (see link below).

New on Tim's Atari MIDI World (TAMW)
I wanted to add more to the bread and butter section (sequencers) so I created pages for the following applications:

Some additions to the algorithmic section:

These belong in the "other" section:


Useful links


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MyAtari magazine - Feature #6, September 2002

Copyright 2002 MyAtari magazine