Saturday, February 14, 2015

The IBM Music Feature Card - Overpriced, Underperforming, Yet Insanely Desirable

The IBM Music Feature Card (IMFC) was one of IBM's last products for its IBM PC/XT/AT family.  Released around March, 1987, it was an 8-bit card that could be used in its PC line, which was deprecated on April 2, 1987 and also in its IBM PS/2 Model 30.  IBM's focus had firmly shifted to its PS/2 line and spent most of its R&D developing Microchannel expansion cards.  In 1990 IBM began releasing systems with ISA slots that could fit the full-length Music Feature card, but by that time, the card has been discontinued.

The IMFC was not cheap at $600.00 ($1,250.00 today) when it was introduced.  This was not uncommon, buying IBM was not cheap.  The card was designed by Yamaha and contained at its core a Yamaha music chip.  The card was also consisted of a complex design of off the shelf logic chips to implement a MIDI interface and features useful to a hardware developer.  Because IBM had exclusive access to Yamaha's chip, the YM-2164 OPP, and the card was incredibly expensive and difficult to clone, no clones ever appeared on the market.

IBM barely marketed the card at all, and IBM products appealed to businessmen and white collar types. Musicians were typically anything but. For little more than the cost of the IMFC, a musician could buy a complete Atari 520ST system, which included a built-in MIDI Interface.  Thus the card was doomed to failure in the marketplace.

IBM still deserves credit for making the first sound card expansion for general PC use.  You certainly could use the card in a non-IBM PC, so long as you had a slot and room to fit it.  Unlike the PCjr. sound chip or the PCjr. Speech Adapter, IBM's card was not tied to a specific computer.  Other PC expansion cards that generated sound probably predated IBM's card, like the Mindscape Music Board included with the PC version of the Bank Street Music Writer, but the hardware was only intended for use with the manufacturer's software. IBM and Yamaha provided a few utilities for the IMFC, including the Compose and Playrec software.  IBM's Storyboard Plus 2.0 has IMFC and PS/2 Speech Adapter support.  Software for the card can be found at Feature Card.  The card came with a diagnostics disk and can be tested with a late IBM PC/XT Advanced Diagnostics disk.  Some software outside IBM and Yamaha also supported it. Electronic Arts released a special, rare version of Music Construction Set for the card.  These include MIDI sequencers like Cakewalk Pro ans Voyetra Sequencer Plus, most of Sierra's games from 1988-1990.

The card itself has two features.  First is an 8-voice sound generator centered around the YM-2164.  This eight voice polyphonic/multitimbral chip can access 240 preset instruments and 96 user created instruments. It generates sound through four-operator FM synthesis and supports stereo sound output.  The sound generator is identical to the Yamaha FB-01 MIDI Module with the exceptions that the FB-01 can save user patches and configurations and has external controls.  The second is a MIDI interface that is used to communicate with the sound generator and other devices.  Windows never supported the MIDI Interface or the card's sound hardware.

The IMFC came with a MIDI breakout box that consisted of one MIDI IN, one MIDI OUT and one MIDI THRU port, all DIN-5s of course.  It allowed the MIDI interface to control external MIDI devices and external MIDI devices to control the sound hardware on the card.  It connected to the expansion cable with nine wires and uses a DE-9 connector.  There is no circuitry in the breakout box, so it can be easily replicated.  IBM provided full documentation for the card's features in its Options and Adapters manual, and it can be found online at  The breakout box is even rarer than the card itself.  It has a PS/2 design.

Competition soon appeared in the face of the Adlib Music Synthesizer Card.  The Adlib at first was marketed as a music creation tool with its Visual Composer software.  The Adlib card uses a two operator FM Synthesis chip from Yamaha, the YM-3812, but Adlib intentionally scratched off the part number to obscure the identity of the chip.  Unlike the IMFC, the Adlib was a simple card which required programmers to access the sound chip's registers directly.  The Adlib was introduced at $219.99, roughly 1/3 of the price of the IBM card and came with software as well.  The Adlib was not a huge hit until it started to be adopted for games toward the end of 1988.  Creative Technology also sold its Creative Music System package as well around this time, but its PSG based sound was not well received and it was not successful.  Roland had been marketing its MPU-401 Interface for several years and had interface cards for the IBM PC and any clone with an ISA slot, but it could be used with any MIDI hardware.  In the days before General MIDI, MIDI capabilities and features varied tremendously from manufacturer to manufacturer and product to product.

The IMFC has a pair of dipswitches to set the address, and there are only two official selections.  If switch one is "OFF", you get the default base address of 2A20 and if "ON", you get the alternative address of 2A30.  Because many cards or systems only decode 10 bits of the I/O address bus, these selections will frequently overlap with I/O addresses 220, 230, 320 and 330.  You may issues if you have a Sound Blaster or a Roland MPU-401 or a Gravis Ultrasound installed at the same address.  It also uses an IRQ, any from 3-7.  Yamaha's software uses the IRQ and is very speed sensitive and does not work in a 386 or faster system.  Sierra's software does not have a problem with system speeds and the IMFC.  Officially, IBM allowed for two IMFCs in a single system, the other two I/O address settings were not documented.  IBM PC/XT slot 8 operation is not supported and it does not fit in that slot or slot 7 in an IBM PC/XT case anyway.

IBM Music Feature Breakout Box
The IMFC with its breakout box has two small advantages over other "modules on a card" like the Roland LAPC-I, SCC-1 and MPU-401AT with a daughterboard.  First, the sound generator can accept sysex from its MIDI IN without any settings in the MIDI interface needing to be changed.  Second, the sound generator can receive MIDI input and send MIDI output.  The sound generators on the Roland devices can only receive MIDI Input, they cannot send MIDI output.  Therefore, you cannot simply dump a game's patches from a LAPC-I by transmitting a dump receive command to the sound generator, the data that the sound generator wants to send will go nowhere.  This allows the card to be used as an FB-01 just by powering on the system.  Additionally, unlike the FB-01, you do not need to turn the memory protection to OFF to allow the sound generator to receive custom patches and configurations.  However, you may need to reset the system with the IMFC between games.

If the IMFC card had been only supported by IBM and Yamaha, it probably would have faded into obscurity and have been almost forgotten.  The IBM marquee would have ensured some level of vintage recognition, but Sierra On-line gave it a lot more.  Sierra, when it developed its SCI engine, focused on supporting music devices for every computer user's budget.  Uses with no sound card would have to make do with the PC Speaker and PCjr. and Tandy 1000 users could hear 3-voice music from their system. Sierra identified the Adlib Music Synthesizer as an appropriate low-end card and the Roland MT-32 with the MPU-401 as a high end solution.  IBM's card was the only other device with any meaningful market penetration and a published Technical Reference manual, so Sierra supported it as well in its SCI engine adventure games, starting with King's Quest IV in September, 1988.

Unfortunately, chip music was not the strong suit of Sierra's in house or contracted musicians.  Their strength was with the MT-32, hence their sound tracks were optimized for that device.  The music for its games simply was not as impressive on the Adlib and Tandy chips.  However, because the Adlib was much cheaper than the MT-32, Sierra at least tried to make their music sound decent on it.  Tandy 1000 systems were still very popular and Sierra was still a strong supporter of that PC offshoot at this time.  If the MT-32 was Sierra's first tier sound device, the Adlib and Tandy were the second tier.  Unfortunately, the IMFC was definitely in the third tier.  Sierra did not spend sufficient resources to make its music sound good on the Music Feature.  Its music scores played to the strengths of the MT-32, not the advanced FM synthesis of the IMFC.  It spent even less time with later supported music devices like the CMS Game Blaster, the Casio MT-540/CT-460/CSM-1 and other synthesizers.

There is no question that the hardware inside the IMFC can be used to make great music, even though access to its registers is indirect via voice parameters.  The YM-2614 is in the same family as the YM-2151 OPM chip.  A very close cousin is the YM-2612 found in the Sega Genesis and Fujitsu FM-Towns.  The YM-2151 was used as one of or the main music chip in countless arcade games and the Sharp X-1 and X68000.  Even the YM-3812 in the Adlib, Sound Blaster and their clones could be coaxed, in the right hands, to produce memorable tunes.  Unfortunately, Sierra's musicians were not the "right hands".  In fact, most of Sierra's games sound much better on the Adlib than they did on the Music Feature, despite the latter having far more potential.  However, the MT-32 and Roland MPU-IPC, at $550.00, was cheaper than IBM's card and totally blew it out of the water once you heard both in any Sierra game.  Ken Williams, President of Sierra On-Line, Inc., rather obliquely recognized this in his letter included in Sierra's games discussing the advantages of sound cards :

"A third card, from IBM, is also of exceptional quality, and out products do support it, but it carries a high price when compared feature by feature with the Ad Lib or MT-32."

Sierra sold the Ad Lib and MT-32 directly but told customers to order the IMFC directly from their local IBM dealer.

Sierra eventually supported the external FB-01 when attached to a Roland MPU-401 interface. The MPU-401 MIDI Interface is totally incompatible with the IMFC MIDI interface.  Most of its games support or can be easily be made to support this music through either the Music Feature or the FB-01.  Here is a list of games and what each supports :

SCI0 Games IMFC FB-01 Notes
King's Quest IV Y Later Only v1.003.006 or later for FB-01
Leisure Suit Larry 2 Y Later Only v1.002.000 or later for FB-01
Leisure Suit Larry 3 Y Y
The Colonel's Bequest Y Y
Space Quest III Y Y
Codename: Iceman Y Y
Hero's Quest/Quest for Glory Y Y
Hoyle's Official Book of Games Y Y
Police Quest II Y Y
Conquests of Camelot Patch Patch
King's Quest I SCI N Y Crashes often with IMFC
Mixed Up Mother Goose Patch Patch

SCI1 Games IMFC FB-01 Notes
Jones in the Fast Lane Patch N
King's Quest V Patch N
Quest for Glory 2 Patch N

Game Arts/Falcom Ports IMFC FB-01 Notes
Sorcerian Buggy Buggy
Thexder 2 Patch N
Silpheed Y Later Only v2.x or later for FB-01

SCI0 Demos and Previews IMFC FB-01 Notes
1988 Christmas Card Y N
Astro Chicken 1 Y Y
Astro Chicken 2 Y Y
Fun Seeker's Guide Y Patch

For the entries in the above table marked Patch, if the game has a IMF.DRV file, all it needs for FB-01 support is the FB01.DRV file, which can be found from another game using the same engine.  If the game does not have an IMF.DRV file, then not only will it need that file but also a file named PATCH.002.  If you can find an FB01.DRV from another game with the engine, it should work as well.  If there is an N underneath the FB-01 column, that means that no working FB01.DRV works with the game. 

The games Sierra released in 1990, for the most part, only supported the IMFC by patches.  After 1990 Sierra discontinued support for the IMFC and other MIDI devices which it had previously provided some support.  By that time, IBM had discontinued the card.  At that point, it only served as a MIDI device which had no Windows support, so interest must have withered away.  No game companies other than Sierra ever supported the IBMC.

When I acquired mine around 2007, I was able to get it for about $120.00 on ebay from one of those crusty sellers who take the worst cell phone pictures and have a vastly inflated sense of value for most of their stuff.  I later found the breakout box for about $40.00.  On January 14, 2016, a fully boxed and complete Music Feature went for $1,225.00.  Cards with the breakout box can go from anywhere from $300-$880.  I believe there are at least twenty specimens of the card known to exist in the hands of various collectors.  Considering what the IMFC was capable of, these prices are unreal.  

Here are links with varied samples of the card's output :

The rather plain, PS/2 style box the card came in can be seen in this video :

If you ever come across someone advertising a CIB Music Feature, you should expect to find inside the box the card itself, the breakout box with an IBM logo, a black retaining bracket to support a full length card, the installation manual and diagnostics diskettes.  The CIB Music Feature that sold for $1,225.00 came with [PC & XT] Diagnostics v2.24, Diagnostics for IBM Personal Computer AT and IBM Personal Computer XT Model 286 v2.07, both on 5.25" floppies and IBM Personal System/2 Model 30 Starter Diskette v1.03 on 3.5" disk.  The included disks and version numbers may vary a bit

IBM Music Feature Cards generally come in two varieties, one with a socketed EPROM in U34 and another with a Mask ROM in U34.  The EPROM cards came earlier than the Mask ROM cards.  However, there are two revisions of the Mask ROM card, the difference being a fix to the diode/resistor/capacitor jumble at C26.  In the older card, there is a diode and a resistor soldered to the legs of the capacitor in a hot-fix way.  In the card I own, the later Mask ROM card, there are plated holes and labels for the resistor and diode.  All the EPROM cards I have seen appear to be the same revision.  I do not know if there are any revisions to the code in the EPROM, but all photos I have seen of the EPROM seem to have the same label over the erase window.

IBM Music Feature Card - Earlier Edition (Wikipedia image)
IBM Music Feature - Later Edition

If you need documentation or diagnostics for the Music Feature, you can find everything you need here : Feature Card - has the technical reference and programs you could have obtained separately. - has the installation manual which came with the Music Feature

There are no drivers for this card, the card only came with Diagnostics disks. You can find them here : Always use the latest dated version.

If you have a Music Feature Card and the EPROM becomes corrupted, you can burn a new EPROM with the firmware located here :


  1. I have acquired the card with the socket-ed EPROM (The NEC EPROM label says X215 D Q). The Yamaha chip YM2184 89 26 52 C. My friend said her deceased husband was performing support with with Yahmaha but I am not sure if this is the normal Yamaha chip.
    I also have the IBM MIDI break out box.
    In addition I have a stand alone EPROM in a box labeled "old BIOS pre-X-BOX.

    Does anyone know if this is the normal IBM music feature card?

  2. LOL i just saw one sold for 370$ USD on ebay
    just a few weeks ago..

    i bought my FB-01 for 35$

  3. In the FB-01 column of the table, what does "New Only" mean?

    1. The "New Only" a bit misleading, means later versions of the game. (See "Notes" column.)

    2. Perhaps "newer" would have been less confusing, but "later" is best.