Yamaha SW60XG

Most wavetable upgrade products are daughterboards that connect to a header on the host sound card. They can be used either to add wavetable synthesis to a card offering only FM synthesis, or to increase the polyphony and/or multitimbrality of a wavetable sound card (that is, the number of notes and the number of instruments respectively which can be played at the same time).

However, there are a couple of drawbacks to this approach. First, although most FM sound cards now have a header for a daughterboard, some of the early products - notably the original SoundBlaster 16 Value - offered no such upgrade path. Second, and more important, the DAC (digital to analog converter) and audio amplifier on the host sound card are used to process the output from the daughterboard. If the original sound card is a budget offering, or even an AWE32, the mediocre quality of this circuitry could seriously degrade the sound from the wavetable synthesiser.

The Yamaha SW60XG addresses both of these potential limitations by interfacing directly to the ISA bus rather than to a header on a sound card. With a built-in 18-bit DAC, analog sound reproduction is phenomenal. Clearly, this product is in quite a different category from most wavetable upgrade cards. In fact, although Yamaha markets the SW60XG as an upgrade, it could just as easily be considered as a standalone wavetable synthesiser, rather like the Roland Sound Canvas but without the MIDI ports.

Installation is as simple as could reasonably be expected. Yamaha has produced what it believes to be unique - a sound card with no IRQ channel to set. It's not plug and play: you need to set jumpers for the MIDI port address, although the default will usually suffice. The only other jumper you may need to alter is the one relating to the type of microphone. The software installation is equally straightforward.

Having installed the card and the software, if you're using it to upgrade an existing sound card, you need to make some external connections between the two cards. There are two possible ways of doing this.

Option one is the preferred route. Patch the line-out socket on the original sound card to the line-in socket on the SW60XG and attach the speakers to the Yamaha card. The SW60XG has no on-board audio amplifier, so this option requires active speakers.

Option two is to patch the output from the SW60XG to the line-in socket on the sound card and attach the speakers to the original sound card. Assuming that the original sound card will drive non-amplified speakers, this route doesn't need active speakers. However, the sound quality will then be degraded.

On a basic level, the sound quality of a wavetable synthesiser depends on the amount of ROM used to store the instrument samples. At 4Mb, the Yamaha SW60XG has more memory than most sound cards, enough for 676 melody instruments and 21 drum kits, which is more than any other non-Yamaha card on the market. Only specialised external MIDI synthesisers boast a higher capacity. However, compression efficiency and the quality of the original instrument recording make a real difference, so that more memory doesn't necessarily mean better sound.

In this respect, I expected the SW60XG to do well, because it's based on the same chipset as the DB50XG daughterboard which has a high reputation in the audiophile community. I wasn't disappointed. The sound quality is extremely good, better even than Roland's Sound Canvas. Wind instruments, which are always a weak area for all MIDI synthesisers, are highly realistic. Piano and bass sounds are full-bodied and vibrant.