Just as a quick preface: I've always loved wavetable daughterboards, despite their lack of support and overall quality. Though I have moved on to better modules (Roland SC-55st instead of SCD-15 and Yamaha MU-10 instead of DB50XG), I always still had the old "lesser" wavetables that sat around being useless, mainly my SoundscapeDB, Waveblaster II, and AdWave 32s. Sure, they aren't the best wavetables, but if I have them why not put them to use?

So for a long time I searched out an answer to find the perfect soundcard for mounting the old wavetables on. I tried just about everything -- Crystal-chipped (4xxx -- Terratec Maestro/Magic S20/SoundGalaxy) boards, ESS boards, Opti boards, Aztech boards, nothing seemed to work quite right though, there would always be some game that had a nasty deficiency with some card that it never had with a Soundblaster Pro 2 or 16. Sure, SB16s are okay for some daughterboards, but the support is finnicky at best and other daughterboards refuse to work period -- plus my IRQ 2/9 is already used by my MPU-IPC-T.

So tired of the endless search for the non-existent perfect card, I decided to take a different approach. I decided it was time to make a wavetable module. At first, I thought about picking up a Korg NS5R, which has daughterboard support built-in to the module, but I could never find very good information on it and you were supposed to send in your daughterboard to Korg to have them custom service the module to properly accept one. So that one wasn't going to work. I played with the idea briefly of paying out the wazoo for an MPU-401/AT, but it had been a long time since I had seen one for sale, and I wasn't ready to shell out around one-hundred dollars for yet another ISA card when I already have an IPC-T hooked up.

I then dug around usenet and found those old schematics from the DB50XG owner group that detailed how to build a PCB for this purpose, but from further digging it seemed that the instructions had come from an old German company's design of a wabetable module. The problem I found is that some of the parts' nomenclatures are very odd, and some of the resistors (such as the 10kΩ8 variable inline resistor) are very rare and hard to find.

So with help from my electronics hobbyist father, I decided we needed to retool the specifications to make a cheaper and more plausible alternative. After getting the specifications for all the parts, finding alternatives, and digging around for hours at a local electronic components warehouse in the sweltering heat, we finally had come up with a decent solution. If there is interest, I will see about making an entire write-up, step-by-step, to making one of these modules with a new parts and schematic list.

Anyway, we finally finished it last night, and it's great. Finally, the daughterboards are free of poor MPU-401 ports, are kitted with MIDI out and thru, and have received their own amplifier and true independent volume control. Of course, for the finishing touch, we had to make a case for it, to turn it into the true old moniker given to these modules-- "black boxes."

So without further ado, here she is:

Here we have the case of the module. As you can see here on the front we have the power switch, the power LCD, left volume control, the MIDI-send LCD (this blinks as MIDI data is being sent), and right volume control. Not pictured on the back of the unit are the two line-out jacks, the two speaker-out jacks (the amplifier powerful enough on this thing that you could easily drive speakers with them), and the MIDI-thru and MIDI-out DIN jacks.

Open it up from the side and who do we have here? It's a SoundscapeDB plugged into the 26-pin header! On the left is the custom-made power supply, and the right is obviously the component board. To save patch cables, the module does not have a MIDI-In jack, but uses a hard-wired MIDI cable instead. Perhaps not the most practical thing, but it can change whenever.

And here, lastly, is the inside. This was before I hooked in the MIDI-thru and out, so it isn't the 100% completed package, but everything else was finished at this time. As you can see, the component breadboard is pretty bare -- it'd be a lot smaller but I wanted a good base for the daughterboards in which I could mount permanent standoffs. It works pretty well so I'm not complaining.

So I guess the lesson is that people who don't have ISA cards, who don't want to settle for poor "clones", or who just want to give their daughterboards a second chance, should not give up hope in finding a good solution. Making one of these modules is definitely doable, even for the amateur, and finally being rid of nasty MPU-401 ports or any host sound card is a relief. Plus it sounds great!