MIDI Circuits; Controllers & Goldstar GMK49

Brian Heywood considers some of the PC‑related products you could include in your letter to Santa this year...

One of the most common questions I receive is "how can I connect up a MIDI keyboard to my PC soundcard?". There are two tasks here: one is to make a cable to get the MIDI signals into (and out of) the card, and the second is to find a reasonable keyboard to let you convert your performance into MIDI. Most soundcards have MIDI capability, but require a special cable to get at the signals — which appear on the card's 15‑pin, D‑type game port socket. The cable has to contain circuitry which can convert the TTL signal levels into the 5mA current loop used by MIDI. Unfortunately, such cables can be difficult to find in the shops, as well as outrageously expensive. However, the circuit is quite simple, so if you're handy with a soldering iron, you can make one yourself. The circuits shown here (see Figures 1 and 2) should work with most SoundBlaster‑type cards, as well as the Gravis UltraSound.

MIDI Controllers

Once you've MIDI‑fied your soundcard, you obviously need some sort of MIDI keyboard or controller, and there are a number of cheap ways to obtain one. You could buy a low‑cost consumer or 'home' keyboard from somewhere like Dixons or Tandy, and this would also give you some extra sounds. If you plan on using your PC‑based MIDI setup to learn how to play, then you really need a keyboard with full‑size keys. This increases the price, but if you learn on a full‑size keyboard, you won't have to start from scratch if you ever decide to use a more advanced keyboard, or a piano.

Goldstar GMK49

Another alternative is to buy a dedicated MIDI controller, like the Goldstar GMK49, which is a 4‑octave, velocity‑sensitive keyboard designed for use with MIDI expansion modules and computer‑based MIDI applications. The GMK49 has all the things you'd expect to find on a synth keyboard, such as standard modulation and pitch bend wheels, but also sports a data entry slider that can be configured to control a number of different MIDI parameters. These include volume, pan, and aftertouch, as well as GM/GS‑specific controllers such as reverb and chorus. Additional features include a footswitch input, an octave switch (high/low), and the ability to run off battery power (six 'AA' cells).

The piano keys are used to select the MIDI channel, change program, and control the data entry slider, and by not including separate buttons for these functions, Goldstar have succeeded in keeping the price down. At just under £180, this keyboard is probably the best 'value for money' controller around at the moment, and is a worthwhile addition to anyone's Christmas stocking. Contact Sound Technology in Letchworth (0462 480000) for pricing information and the whereabouts of your nearest retailer.

MIDI Your PC Painlessly

Of course, if you have a computer, you may not want to go through the angst of installing a soundcard — or even a MIDI interface. Or you may have a portable PC, which means that neither of these alternatives is an option. Don't worry, you can still use that spare serial port to get your PC talking MIDI. I've covered serial (and parallel) port interfaces in previous columns, and there are also sound modules like the Yamaha TG100 and the Korg AG10 which offer you hassle‑free MIDI interfacing when plugged into your PC.

One interesting 'all‑in‑one' solution is the Roland SK50, which is a multitimbral keyboard based on Roland's Sound Canvas technology. This unit incorporates a 5‑octave (61‑key) velocity‑sensitive keyboard, a 16‑part multitimbral GS/GM wavetable‑based synthesizer, and a built‑in stereo amplifier and speakers. What makes it especially suitable for use with the PC is its built‑in serial port interface, which allows you to dispense with the traditional MIDI interface. An added bonus is the external audio input — so if you do have a decent soundcard, you can hear that as well. The only disadvantage I can see (compared to the GMK49) is the lack of pitch bend and modulation wheels. At around £570, it is more expensive than a simple keyboard, but it does have the advantage of being independent of the PC, so you don't have to boot up the computer to tinkle the old ivories. For more information, contact Roland on 0252 816181.

Naturally, you don't have to stick with a piano‑style MIDI controller. Guitarists can interface directly to their PC using the G‑Vox Bridge system from Lyrrus (contact Koch Media on 0252 714340 for more information), while drummers might like to check out something like the KAT percussion controllers (contact Zildjian Music, 0344 872262).

More Stocking Fillers

For those who are interested in rolling their own MIDI applications, Artic Software in the US have released a set of custom Windows controls for Visual Basic. Called MIDI CoolTools, the package includes MIDI input and output controllers, knob, fader and slider controls, and even the option to read and write standard MIDI files. Artic say they have controls that will shield you from the intricacies of the Windows API, and allow you to concentrate on creating your program. The software costs $59 and is available from Artic on 0101 414 5344309 (fax: 0101 414 534 7809). Visa and Mastercard are accepted.

For The Guitar Player In Your Life

Also from the US comes Solo Assimilator, which consists of a set of Rock, Jazz and Blues guitar solo MIDI files. These are designed to help you improve the quality of your playing by increasing your 'vocabulary' of guitar phrases. The solos are transcribed from recordings of famous guitarists such as BB King, Muddy Waters, Buddy Guy and ZZ Top, and all come with notation and tablature to help you follow what's being played more clearly. The music is supplied in both Standard MIDI file and Band in a Box v.5 formats, on either 3.5‑inch or 5.25‑inch disks, and includes complete backing tracks, so you can hear the solos in the appropriate context. Because the solos are supplied as MIDI files, you can slow sequences down without altering the pitch, or transpose the material into the key that you want to use. The files cost $35.95, and can be purchased from Lil' Johnny Enterprises, 20 North Allen Avenue, Richmond, Virginia, 23220, USA, with payment by cheque or money order. For more information, you can phone Bob Webb on 0101 804 3595917 (fax: 0101 804 3538405).