The Windows multimedia revolution grinds on... This month Brian Heywood looks at a couple of products that may help you find multimedia heaven with the PC.
One of the biggest players in the Windows soundcard business doesn't sell any PC specific hardware at all! You'll find Yamaha's OPL FM synthesizer chips on most SoundBlaster compatible soundcards, and a few that aren't. As I understand it, Yamaha developed the OPL chips for specifically for arcade games, using technology developed for their music products. When Ad‑Lib brought out their games music card, they used the OPL2 chipset to get 11 'two operator' FM voices; Creative Labs then added sample replay and used the OPL3 chips to give 22 voices.
In terms of sound quality, these OPL based cards sound pretty naff, even when compared to quite modest keyboard synthesizers. This is not surprising, since the technology used is at least two generations out of date. OPL 2 and 3 sound good compared to the PC's built‑in speaker (what doesn't?), but you couldn't use them for any serious music application. So we have the somewhat ludicrous situation of sound cards that can replay CD‑quality sampled sounds — with a synthesizer section that sounds like a Nintendo Gameboy.
Not all soundcards have followed the OPL route; Turtle Beach, Gravis and Roland have used different forms of wavetable synthesis and Media Vision are pursuing 'Wave Guide' synthesis (as found in the Yamaha VL1). We should also be seeing some DSP‑based soundcards, using a version of Peavey's DPM technology, in the next year or so (see last month's column), as cards using the Motorola PCMedia chipset appear. There are also wavetable daughter boards available for some of the more expensive OPL‑based soundcards, allowing you to take advantage of the improved sounds while maintaining compatibility with the older cards. Quite frankly though, I'd recommend that you get the soundcard's MIDI kit and an external GM compatible sound module like the TG100 or the Korg Audio Gallery to give you a much more flexible system, which will also sound better (due to the built‑in effects like reverb).
Logitech Soundman Wave
If you need to maintain compatibility with the older OPL sounds, the wavetable add‑on or external GM module is a fairly expensive route to decent sound quality. There is now an alternative. Yamaha have produced an OPL4 chipset which adds their AWM sampled sound technology to the older FM sounds. The first card that I've seen that uses OPL4 is Logitech's new SoundMan Wave MPC compatible soundcard. Logitech are well known for their range of peripherals for the PC, so it's not surprising that they include multimedia sound in their product range.
The SoundMan Wave is a 16‑bit ISA bus soundcard with an OPL4 synthesizer, sound compression hardware, a SCSI interface for a CD‑ROM drive and around 7Mb of bundled software and sound files. As mentioned above, Logitech (or rather Yamaha) have added wavetable synthesis to the standard FM sounds, giving much higher quality music replay; most obvious in the drum sounds, but all the instruments sound generally better. The card has 2Mb of sample data stored on ROM. The SoundMan Wave also has decent (up to 44‑note) polyphony, which is better than a lot of synthesizers. In terms of software compatibility, the card emulates both the SoundBlaster standard and the Roland MPU 401 MIDI specification. I think the card's standard GM sound set must be a combination of FM and sampled sounds, since the drums and piano were obviously samples, but I thought some of the synth and bass sounds were FM.
The card can also record and play 16‑bit stereo sound files at sample rates between 4 and 44.1kHz. The specification quotes a signal‑to‑noise figure of 88dB using the line‑out socket which — as usual — should be treated with a certain amount of caution. The card has dynamic filtering to reduce aliasing and generally get the best sound quality, regardless of the sample rate. One interesting feature is that the card has additional hardware to support the Microsoft ADPCM and CCITT sound compression techniques. Unfortunately, there is no way of taking advantage of this feature, since the supplied software won't let you create compressed audio files, and the supplied Windows Wave driver can't play them back.
The card has both line and microphone inputs on the back plate, and an internal connection for the audio output of a CD‑ROM drive. There are two audio outputs; one amplified (4 Watts) for driving a pair of small speakers directly, and a line out that can be taken to a stereo amplifier or powered monitors. I find this arrangement quite convenient, since it means that I can use a cheap set of speakers for normal Windows noises, and use the hi‑fi when I want to get a particularly 'big' sound for an MPC application like MS Instruments (or even a game!). At around £199, the card is more expensive than the Gravis UltraSound, and probably not up to the sound quality, but if you need OPL compatibility, and still want reasonable sound quality, check out the SoundMan Wave (phone Logitech Customer Relations on 0344 891452).
Lyrrus G‑Vox
Last month I mentioned the G‑Vox guitar system in passing — since then I've had a chance to have a very brief play on a prototype system. The G‑Vox is designed to interface a guitar, whether electric or steel string acoustic, to your computer. The system consists of three parts: an electro‑magnetic pickup, an interface box, and a software package for the PC or Apple Mac. The pickup fits over the strings, is fixed to the guitar body with small suction cups, and has a very neat adjustment system that makes it easy to set up. The interface unit, which connects to the computer's serial port, can either clip to your belt or rest on the floor, and is featureless apart from a gain adjuster for each string. The interface is controlled entirely from the software, which appears to download a control program when it detects the presence of the interface.
The software for the PC is DOS‑based — with a Windows version on the way apparently — and currently comes in two flavours, either riff or chord tuition. Each package uses the PC's soundcard and screen to show you what you need to play, and then monitors what you do with the guitar, correcting if necessary. For the Riffs package Lyrrus has booked a number of guitar heroes to play in some of their favourite 'guitar chops', meaning that you don't have to wear out your records trying to get that riff just right. I don't have the full details of which soundcards are supported, but I imagine that the SoundBlaster will be in there somewhere and I do know that Gravis are doing a special patch set for their UltraSound card.
If the G‑Vox was only useful for guitar tuition, it would have fairly limited appeal, but Lyrrus are also including the ability to create MIDI files using the system, making it look like a relatively cheap way to add guitar MIDI to your sequencing set‑up. Actually, the MIDI aspect is a good example of lateral thinking. One of the traditional problems with pickup‑based guitar MIDI systems is the delays inherent in determining the pitch of the note you are playing, meaning that you get a variable conversion delay across the guitar fretboard. Lyrrus get around this problem by not trying to do the conversion in real‑time; the start of note (i.e. when you pluck the string) can be accurately determined from the attack portion of the note, and the pitch can then be calculated and associated with the start time. You have to monitor the performance using the acoustic output, but you get an accurate representation of your performance, which you can save as a MIDI file and then import into your sequencer. Clever stuff, eh?
The final icing on the cake is that Lyrrus are working closely with Howling Dog System to integrate the G‑Vox into the PowerChords guitar sequencer, allowing you to directly enter picking patterns, chord shapes, bass lines and melodies. When this happens, the G‑Vox/PowerChords will be a very simple and powerful way for guitarists to get into MIDI without having to learn how to play a keyboard. I've been promised a loan system when the full G‑Vox system is released sometime later this month, so expect a full review in the near future. If you want to find out more about the G‑Vox system, contact Kim Bolton at Optech in Farnham on 0252‑714340.