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The SFX Series: Sound Expander, Sound Sampler, Music Maker/Music Maker II, External Keyboard

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Intending to use pictures or text from this page? Please read this notice. Last modify 21 January 2018.

"Family Portraits"
.jpg Image of My SFX Units (55K, my units), .jpg Image of the SFX Series (38K, courtesy Markus Mehring).
My picture shows the Music Makers, the External Keyboard, the Sound Expander and the Sound Studio software package; Markus' shows the Sound Expander, the Music Maker 64, the External Keyboard and the Sound Sampler.

First, some big thanks: Randy Winchester, for getting this entry started; a large number of corrections and additions (especially for the Sound Expander) from Magnus Eriksson; Alan Drew, one of the original members of the development team; Michael Kurz, one of the software developers; Todd Elliott, who found some information on Canadian releases of this series; Nicolas Welte, who found much technical data in several back issues of 64'er; Markus Mehring, for most of the photos on this page (very complete!) and a fair bit of history; and Richard Atkinson for the FM Sound Expander and some useful E-mail from the original designers.

The Commodore 64's most enduring claim to fame was being the first major home computer to have a sophisticated synthesiser built right in. So, why did Commodore jeopardise that by distributing these devices? This is especially puzzling given Commodore's other experiments with the SID chip (see the entries for the Digi-Drum and Music Synthesiser). One reason may have been limited stocks of SID chips and/or difficulty with their manufacture, which was the cited reason for the death of those two SID-based projects.

Whatever Commodore's motivation(s) might have been, the corporate affiliations are known a bit better. The SFX in "SFX series" is short for the now defunct(?) SFX Computer Software, a division of UK corporation Music Sales Limited. In fact, Commodore did not own the copyright on the SFX devices nor the SFX software; all of them appear to be owned by MS Ltd and the arrangement with Commodore was strictly for distribution. These devices seem to be work-ins for Music Sales' lines of sheet music, songbooks and music peripherals, and the SFX devices were probably a cooperative venture to capitalise on the then-growing interest of computerists in music synthesis. Most of these devices appeared between 1984 to 1986 (an article from the Toronto PET Users Groups, forwarded to me by Todd Elliott, fixes the Canadian introduction of the Music Maker at November 1984); no one knows exactly how long they were manufactured, but Gazette 7/89 mentions the units as still available for purchase thus implying that they were at least manufactured up to or near that date.

According to designer Lyndsay Williams (in a message passed on by Richard Atkinson), the SFX series was born in 1982 when Williams demonstrated a Sinclair Spectrum-based sound sampler device to MS Ltd contractor Richard Watts and his company, Richard Watts Associates. This design was sold to Commodore and became the Sound Sampler, who then commissioned the Sound Expander, designed by both Williams and Watts. Williams also wrote some of the early series software.

The release range of the SFX series is a point of some question, as well as their intended market point. The original UK pricelist (.gif, 23K) gives the core Sound Expander FM module at £100 (approximately USD$125 at contemporary exchange rates), with the Sound Sampler at £70 and most music albums around £10. This is roughly comparable to an article in Gazette 7/89 reporting their MSRP in the United States ranged around $80-$120. However, in Germany, the prices of one supplier ranged as high as 399DM for the Sound Expander alone, an obscenely grotesque purchase price by anyone's estimation (compare with the 64 itself which was around 250DM at that time). Regardless of their price point, it is generally agreed that the series greatly lacked the software functionality to have any appeal at all to professional musicians, who might have bought the devices if the software quality matched up, and the variable market pricing likely placed them out of reach of casual enthusiasts. Like so many of the devices in this museum, the units are in general adequately functional and some even excellent, particularly the Sound Expander; had they been targetted at a more professional market and produced more slickly, the SFX series might have found a niche. Of course, if they'd done that, you wouldn't be reading about them here, would you?

The one thing that Commodore did do right with the SFX series was a fairly impressive range (if not functionality) of software, with quite a number of titles including playalong songbooks, the Sound Studio MIDI controller/music studio (.jpg, 24K, courtesy Markus), and other included and optional programs. Unfortunately, these packages also suffered from the price bloat that plagued the hardware. Most of the SFX series ended up in the UK -- almost none made it to American shores, despite one known distributor (though it is still an open question whether any were actually sold); some also appeared in Germany, according to Markus, who found ads for them running until 1989, and a few arrived in Australia, all of which were likely UK imports. The Music Maker keyboard is the only known unit to have wide distribution outside of Europe.

Commodore did do some package deals with the SFX series, including this large pack-in deal featuring the External Keyboard (which it calls the "Music Keyboard"), Sound Expander ("FM Sound Module") and Sound Studio software (box views of my unit: front (61K), side (161K)). This particular offer came from the UK and carried a price tag of £149.95. A decent deal, but its relatively low cost suggests Commodore UK was trying to blow their inventory out by that point. Indeed, the units inside this box were simply within their regular retail packaging; no attempt to customize it further was apparently performed.

Eventually Alan Drew ported the software to MSX when Phillips approached MS Ltd to bring the devices to their MSX computers, but this appears to have had an even less well-known rollout than the Commodore-badged devices. A good number of SFX units are still out there, and now there are two Sound Expanders in the USA that I have confirmed as well (mine :-), and Randy Winchester's), as well as Jorge Diaz, who reports in from Mexico with his unit. Most extant units are Sound Expanders; a few people have the External Keyboard and the Sound Sampler. The Music Maker is best known in its (original?) form as the Sight & Sound Incredible Music Keyboard (see that entry), although Jorge has a Music Maker keyboard himself.

Sound Expander (FM Sound Module)

Complete Views of the SFX Sound Expander (.jpg except where noted, my unit)
Box Front (58K) | Box Rear (72K) | Box Contents (66K) | Portrait (71K) | Mainboard (59K) | Backplate (41K) | Stickers (59K) | Fakebook/Songbook: Cover (49K), Introduction (32K, .gif) | In Action with the SX-64 (38K, using the Sound Expander in one of my SX-64s connected to the Power Mac G5 to record)

Views of the SFX Sound Expander Package (.jpg, courtesy Markus Mehring)
Sound Expander and Software (23K) | Sound Expander, Box, and Keyboard (25K)

MP3 Audio (access-controlled, please follow prompts)
Sonata from Composer Suite (770K MPEG-1 Layer 3 audio, 160Kbps CBR encoding). This is the demo tune included on the disk version of the Sound Expander software (links below). It is a very nice demonstration of how well implemented the YM3526 is in this device.

Programming the AdLib/Sound Blaster (information on the YM3812). A few notes parenthetically on this; the detection routine does not work for the YM3526, and neither does it support multiple waveforms like the 3812.
Schematics of the SFX Sound Expander

FM Sound Expander Software
Screenshot (.gif, 2K) -- from Frodo v4.1.

Disk image: try FUnet's disk version in compressed .d64 (copy protection stripped, see the index page for more information). This includes the full Composer and the impressive demonstration song you can hear in the .mp3 above which I showed off at VCF 7. For a change of pace (or if you can't use .gz), try my freeze of the Tape Version, FM Sound Expander Software (170K). This is a uncompressed .d64 disk image containing a Final Cartridge III freeze of the tape version of the software (considerably more limited; cannot load new riffs or voices, and has only one demo song). Tested working on my 128DCR with the Sound Expander. Must load from device 8 and includes the FC3 fast boot loader.

With regard to both versions: Yes, you need the Sound Expander cartridge to actually hear music. No, I don't know where you can get one from. Use F1-F3 to move left-right/up-down with the pulldown menus, and F7 to select or deselect options. If you don't have the External Keyboard, the software defaults to the standard key assignments for the Music Maker (.gif, 21K, from the SFX Sound Expander Manual).

SID is a fantastic sound chip, but it looks like Commodore didn't think it was good enough. At least, that seems the only explanation for why they decided to rebadge this device.

The Sound Expander is based on the Yamaha YM3526 OPL FM synthesis chip, driven at 3.579545 MHz, providing nine voices -- the manual says eight, but maybe that's just the software. Descendants of this chip power the PC AdLib and SoundBlaster cards; the device, according to Magnus Eriksson, is in fact programmed very similarly to the AdLib's later YM3812 OPL2 chip. According to Randy Winchester, the sound quality actually far surpasses AdLib and SB, however: much less noise, and excellent isolation from the data bus. Judge it for yourself with the music sample I took from my unit above; in my opinion, the sound is indeed very crisp and clean, and, for an older OPL synth, quite nice and bright-sounding.

The Sound Expander has a very similar appearance to the Magic Voice cartridge, externally, with the same cartridge passthrough and casing (in fact, look carefully on the case, and you can see where the holes for the Magic Voice's extra RCA jack and those mysterious three metal humps on the cartridge end were filled in with plastic), and came with a songbook, chords and note stickers for the Music Maker (as depicted above), a phono plug (not in my package), a manual, and the FM Sound Expander software on tape or disk. The tape software is fairly dire -- it can't sequence or record, has no auto-accompaniment (rhythm only) and cannot load new riffs or songs, but it does have a fairly nice interface, gives you access to the full range of instruments available, the "Riff Machine" is pretty cool if somewhat inflexible (an auto-play feature with pre-programmed riffs attached to notes), and in general the program is relatively easy to use. On the other hand, the disk software is much better, and while obviously coming up short as a true sequencer, it does feature a full complement of utilities (though unfortunately not well integrated) and a beautifully designed on-screen composer. The pack-in software was written by Alan Drew, Mark Palmer, Chris Maciejewski and Azhar Chaudhary with some later work by programmer Michael Kurz, who was only 16 at the time and worked on the software during his school holiday.

The Sound Expander was designed to interface fairly simply through software, programmed through the normally unmapped I/O space at $DF00-$DFFF. Ports one, two and three occupy $DF40, $DF50 (write only) and $DF60 (read only), respectively, with the piano keyboard (see the entry on the External Keyboard below) interface lines occupying $DF08 through $DF0F (read only). Mirrors of the keyboard registers also appear every 32 bytes afterwards, at $DF28, 48, 68 and so on. (For that matter, the OPL chip repeats every 128 bytes; so, there's a register mirror starting at $DFC0.) The piano keyboard plugs into a 16-pin port on the side of the unit (see the Internals/Mainboard pictures for the port connections). Port one selects the internal YM3526 register of interest and port two is the data to store in that register, identical to the modern SB $0388 and $0389 music ports for your standard PC sound card. Timing is particularly painful (adapted from an example by Magnus):

        ; load x with register, a with data for that register

        stx $df40               ; select ym3526 register
        nop                     ; wait 12 cycles for register select
        sta $df50               ; write to it
        ldx #4
lup     dex
        bne lup                 ; wait 36 cycles to do the next write
Longer delays don't do any harm, so you can drive the device with POKEs (it will just be much slower, of course, from BASIC). Magnus points out a convenience of the device is that you don't have to keep selecting the register over and over; you can just pick the register and then write lots of data to it, allowing things like arpeggios to be done by selecting the frequency register and then writing data to it at 50 times/sec. The AdLib programming manual above contains how to generate sounds through the YM3812 chip in the AdLib card, and much of the register mapping also applies to the Sound Expander's YM3526 except, naturally, for the advanced features of the OPL2 that the YM3526 does not support.

The Sound Expander is, unbelievably, quite upgradeable. Richard Atkinson explains that the YM3812 OPL2 may be substituted directly for the YM3526. (The 3812 adds multiple waveforms and a 'drum mode' according to Magnus.) The pinouts and voltage requirements are identical, and the extra registers in the YM3812 are available once enabled through their select register; the YM3812 is also, naturally, completely software compatible with the YM3526. YM3812s can commonly be found on old PC sound hardware, particularly the AdLib, SoundBlaster or very early SB Pro cards; the Aztech Sound Galaxy also apparently has them. The only other unique IC on the Sound Expander board is the Yamaha YM3014B, a D/A converter (the little eight-pin IC on the lower right); everything else on board is TTL logic and off-the-shelf components, making it very possible to build your own clone inexpensively.

The mainboard on my unit carries the cryptic notation "Issue 6" which alleges there are other versions of the board, but the differences are currently a mystery. Sami Ilmonen reports an "Issue 6B" has been found in the wild, but comparison of the board and components show they are practically identical.

Magnus notes that the Magic Voice, since it only occupies the first few locations of $DF00, might co-exist with the Sound Expander. I've never gotten up the courage to test them together, though.

In the USA, the announced MSRP for the Sound Expander was $90, but sans software (an additional $30); the £100 UK package did include software, thus bringing the pricepoints nearly identical. The 399DM German retail price must have been one heck of an outlying datapoint.

Sound Sampler

.jpg Image of the SFX Sound Sampler, Software and Microphone (22K, courtesy Markus Mehring)

.jpg Image of Included Software/Box (40K, courtesy Markus Mehring)

.jpg Image of SFX Sound Sampler Mainboard (97K, courtesy John Selck). Rotated to allow the chip markings to be more easily read.

The series' kick-off device designed by Williams, the Sound Sampler offered users the ability to record and playback sampled sound. In concept, the idea was good and certainly appearing at the right time when people were beginning to experiment with computer-created sound; it even did primitive DSP effects, including an echo/delay (the left "Feedback" control; the right control is volume). In practise, however, describes Randy, it was a "piece o'junk" -- it can only record about 1.4 seconds of sound, according to Markus, and most knuckleheadedly of all cannot create sound files to be used in people's programs. The Sound Sampler was not intended as an add-on for the Sound Expander (and in fact they probably would not coöperate together anyway); it was an SFX product of its own. Commodore kindly included a microphone with the device and software.

Pricing again was a serious issue for the Sound Sampler; in Germany, it had a positively perverted list price of 270DM (!). Although the other SFX devices had a USA distributor and MSRP, the Sound Sampler curiously did not appear to. In the UK, the MSRP for the Sound Sampler was £70 (approximately US$88 at contemporary exchange rates).

Like the Sound Expander, the Sound Sampler has an "issue" number, alleging other mainboard versions exist.

The tape version of the FM Sound Expander software has a scrolltext in its loader ("NOVALOAD CBM 28", if you're interested) that bills the Sound Sampler as MIDI compatible. This is true, but only if you convert the port.

Music Maker, Music Maker II

Views of the SFX Music Maker and Music Maker 128 (.jpg, my units)
Portraits, 64 and 128 Versions (42K) | Music Maker 128 Box (92K) | Music Maker 128 Pack-Ins (54K)

.jpg Image of the SFX Music Maker (36K, courtesy Markus Mehring)
.jpg Image of the SFX Music Maker (35K, enlarged from Sound Expander box)

Key Assignments for the SFX Music Maker (.gif, 21K, from the SFX Sound Expander Manual)

The Incredible Music Keyboard versus the Music Maker, reprinted from Toronto PET Users' Group magazine 2/85 (.gif, 59K, courtesy Todd Elliott)

This is not exactly a technical achievement, but here it is for the sake of completeness. The Music Maker, also "created" (we'll get to this in a moment) by MS Ltd., was nothing more than a keyboard overlay which purported to turn your system into a piano. It came in its original form (Music Maker 64), an updated version (Music Maker II 64) which only seems to differ in pack-in software, and a single 128 version (Music Maker 128). Both units sit over the first couple keyboard rows with a cutout exposing the function keys.

Again, the most startling thing about these units were their prices. In the UK, the basic Music Maker 64 package was £20 (US$25) for simply the plastic overlay and software. If you wanted to upgrade to the Music Maker II 64 software package, that was another £5 (US$7), and if you had a 128 and wanted to use the Music Maker II 128 (which also included a songbook), that would set you back £30 (US$38). Although these are a bit on the high end for what you're getting, they pale in comparison to the advertised German list price: 99DM for the 64 and an astronomical 118DM for the 128 (for comparison, the 64 itself was 250DM)! Extra songbooks could be had for £9 (US$12) in the UK, but the German ad wanted 39DM (coughhacksputter). Ultimately, the Music Maker was announced in the United States for the rather better price of $10 by 1989.

The FM Sound Expander software uses Music Maker keys as its piano keyboard layout, if you don't have the external keyboard to plug in.

The Music Maker, as explained above, probably has the widest range of the SFX series, appearing in Canada and Mexico (reported by Jorge Diaz), and as part of at least one unusual pack-in known in Australia: according to 'John vl' it was included with the 64, a Datasette, some tape software (presumably including some music applications) and programming books. The Sound Expander did not come with it, and it is unclear if this was a real Commodore pack-in deal or merely a third-party sell-off.

But wait, the story gets even more sordid! USA audiences may remember a virtually identical device called the Incredible Music Keyboard, sold by American software company Sight & Sound Software. According to an article published in the February 1985 Toronto PET Users Group magazine (forwarded to me by Todd Elliott), SandS developed the IMK at a cost of around US$75,000. During this time, their European office head John Van Til quit his job and was hired at Music Sales, who opened negotiations with SandS in summer 1984 to license or distribute the IMK. Those negotiations eventually did not progress, but the Music Maker emerged anyway in the fall of 1984, nearly simultaneously with the Incredible Music Keyboard. SandS's George Staleos was furious at the nearly identical copy, exactly the same except for the logo, playalong book and pack-in software (which, if it's any consolation, was considered to be better with the IMK). Van Til refused to acknowledge any connection, and it is unclear if any legal proceedings resulted over the flap. Interestingly, of the two, only the IMK had wide distribution in the United States, possibly because of the threat of legal action. I have an IMK and still wonder how much my folks paid for it. :-)

External Keyboard

Ah, now this is more like it. For a good view of the keyboard, see the Family Portrait (.jpg, 55K) or the Sound Expander with Box and Keyboard (.jpg, 25K).

This 61-key keyboard, bafflingly billed by Commodore as 49, was simply an 8x8 matrix with diodes in series on each contact to help debounce. An add-on for the Sound Expander itself, it mapped into the Sound Expander's registers and was read from there (see the Sound Expander's entry). The keyboard plugs into a 16-pin port on the Sound Expander's side panel. The travel depth on my unit is not unreasonable but the keyboard feels very plasticky and has no velocity sense whatsoever. Its price tag in Germany was an ungodly 280DM, but around $80 as announced in the USA, although for some reason it was not listed in the original SFX UK price list.

The External Keyboard does not seem related to the Commodore MIDI Keyboard or Commodore Music Synthesizer.