Mac OS 9 Lives

Digital Audio Workstation & MIDI => Audio & MIDI Hardware => Topic started by: smilesdavis on September 18, 2026, 11:56:26 PM

Title: Macintosh MIDI Interfaces - Timeline
Post by: smilesdavis on September 18, 2026, 11:56:26 PM

Macintosh MIDI Interfaces — Serial / USB / PCI / FireWire Timeline
Scope: dedicated Macintosh MIDI interfaces and the host hardware needed to keep them usable on Classic Mac OS, with emphasis on Mac OS 8/9. Audio interfaces are excluded unless their FireWire/mLAN implementation is historically important to MIDI. Dates are first defensible introduction/release evidence, not necessarily the date of the last driver. ?=unresolved. “physical Out” means duplicated jacks may exceed the number of independently addressable MIDI ports. Forum evidence below deliberately excludes posts authored by smilesdavis; product facts are cross-checked against period reviews/manuals where available.

Software / timing shorthand

OMS=Opcode Open Music System.
FM=MOTU FreeMIDI.
MTP=MOTU MIDI Time Piece multi-port protocol/emulation.
MTS=MOTU MIDI Time Stamping; useful only with software that supports it.
AMT=Emagic Active MIDI Transmission; timestamp-style scheduling used by compatible Emagic/Logic software.
LTB=Steinberg Linear Time Base; timestamped output scheduling used by compatible Steinberg software.
Classic Mac OS does not provide the modern generic USB-MIDI class-compliant path familiar from OS X; most USB devices here need their period vendor driver plus OMS/FreeMIDI or a vendor-specific MIDI layer.

Chronology — dedicated MIDI interfaces

Year	Manufacturer	Model	Host connection	MIDI I/O	OMS / FreeMIDI / timing	Classic Mac OS	Driver	Notes
1990	MOTU	MIDI Time Piece I (#post_motu_mtp1)	Mac serial	8×8 / 128 ch	MTP; later FM / OMS-MTP path	?→9.x	FreeMIDI/MTP driver; OMS MTP driver	MOTU's first hardware; SMPTE; networkable
1991	Opcode	Studio 5 (#post_opcode_studio5)	Mac serial ×1/2	15×15 / 240 ch	OMS native; MTP emulation	?→9.x	Opcode OMS Studio 5 driver	68000-based processing; patchbay/SMPTE; networkable
1992	Opcode	Studio 3 (#post_opcode_studio3)	Mac serial	2 In / 6 physical Out; 32 ch addr.	OMS; SMPTE/MTC	?→9.x	Opcode OMS Studio 3 driver	2-port multiport interface + 2×6 patchbay
1992	Opcode	Studio 4 (#post_opcode_studio4)	Mac serial	8 In / 10 physical Out; 128 ch addr.	OMS native; MTP emulation	?→9.x	Opcode OMS Studio 4 driver	OMS processing; SMPTE; up to four units
1993	MOTU	MIDI Time Piece II (#post_motu_mtp2)	Mac serial	8×8 / 128 ch	MTP; later FM / OMS-MTP path	?→9.x	FreeMIDI/MTP driver; OMS MTP driver	128 scenes; front-panel standalone operation
1993	MOTU	MIDI Express (#post_motu_express)	Mac serial	4×6	MTP-aware / later FM	?→9.x	FreeMIDI/MOTU serial driver family	Patch matrix; LTC→MTC/DTLe sync
~1994	MOTU	FastLane Serial (#post_motu_fastlane_serial)	Mac serial	1 In / 3 Out	standard serial / later FM	?→9.x	FreeMIDI/MOTU serial driver family	simple non-USB FastLane; forum-dated
1996	MOTU	MIDI Timepiece AV — serial (#post_motu_mtpav_serial)	Mac serial	8×8 / 128 ch	MTP; FM; OMS-compatible path	?→9.x	FreeMIDI MTP AV serial driver; OMS path	adds ADAT, WC, video and Digidesign SuperClock sync
~1996	MOTU	micro express — serial (#post_motu_microexpress_serial)	Mac serial	4×6 / 96 ch	FM / OMS-compatible apps	?→9.x	FreeMIDI MOTU serial driver family	patchbay + SMPTE-to-MIDI synchronizer
1996	MOTU	MIDI Express XT — serial (#post_motu_xt_serial)	Mac serial	8 In / 8 addr. Out; 9 physical Out	FM / OMS-compatible apps	?→9.x	FreeMIDI MOTU serial driver family	128 ch; SMPTE/MMC; presets
1996	Opcode	Studio 5LX (#post_opcode_studio5lx)	Mac serial	15×15 / 240 ch	OMS native; MTP emulation	?→9.x	Opcode OMS Studio 5/5LX driver	16 MHz 68000; 256K RAM; 128 OMS Studio Patches; up to six networked
1997	Opcode	Studio 64X (#post_opcode_64x)	Mac serial	4-port / 64 ch; 6 physical Out	OMS	?→9.x	Opcode OMS Studio 64X driver	patchbay + SMPTE; successor branch to Studio 3/4 class
1998	Emagic	Unitor8 (#post_emagic_unitor8)	Mac RS-422 serial	8×8 / 128 ch	OMS driver; FreeMIDI emulation; later AMT-family stacking	7.5.3+ serial	Unitor8 OMS driver + Unitor8 Control	LTC/VITC; 32 standalone patches; up to eight per Mac serial port
1998	Opcode	Studio 64 XTC (#post_opcode_64xtc)	Mac serial	4-port / 64 ch; 6 physical Out	OMS	?→9.x	Opcode OMS Studio 64 XTC driver	64X successor; expanded sync incl. WC/ADAT/video functions
1998	Opcode	Studio 128X (#post_opcode_128x)	Mac serial	8 In / 8 addr. Out; 9 physical Out	OMS	?→9.x	Opcode Studio 128X OMS driver	128 ch + SMPTE
1999-09	MOTU	FastLane-USB (#post_motu_fastlane_usb)	USB	2×2 / 32 ch	FM + OMS; later MTS-capable	8.6–9.x	MOTU USB Driver + FM USB + OMS USB drivers	bus powered; MIDI Thru; first small MOTU USB model
2000-01	Emagic	AMT8 (#post_emagic_amt8)	USB + Mac RS-422 serial	8×8 / 128 ch	AMT with Logic; OMS; FreeMIDI/MTP emulation	serial ?→9.x; USB 9.0.4+ in later shared spec	Unitor/AMT OMS driver + control software	7 rear + front port 8; standalone patching
2000	Emagic	Unitor8 MkII (#post_emagic_unitor8mkii)	USB + Mac RS-422 serial	8×8 / 128 ch	AMT; OMS; MTP/FreeMIDI path	7.5.3+ serial; 9.0.4+ USB	Unitor8 OMS driver + Unitor Control	flagship sync version; mixed Unitor8/AMT8 chains supported
2000-07	Emagic	MT4 (#post_emagic_mt4)	USB	2 In / 4 Out	OMS; direct Logic support	8.6.x/9.x	Emagic MT4 USB/OMS driver	small USB patchbay interface
2000	MOTU	MIDI Timepiece AV — USB (#post_motu_mtpav_usb)	USB + Mac serial	8×8 / 128 ch	FM + OMS; MTS-capable with supporting software	8.6–9.x	MOTU USB MIDI installer + FM/OMS drivers	USB generation retains sync/network functions
2000	MOTU	MIDI Express XT — USB (#post_motu_xt_usb)	USB + Mac serial	8 In / 8 addr. Out; 9 physical Out	FM + OMS; MTS-capable with supporting software	8.6–9.x	MOTU USB MIDI installer + FM/OMS drivers	USB successor to serial XT
2000	MOTU	micro express — USB (#post_motu_microexpress_usb)	USB	4×6 / 96 ch	FM + OMS; MTS-capable with supporting software	8.6–9.x	MOTU USB MIDI installer + FM/OMS drivers	SMPTE / MMC / standalone patching
2000	Yamaha	UX256 (#post_yamaha_ux256)	USB	6 MIDI pairs + 2 TO TG; logical 16 Out / 8 In	Yamaha USB MIDI driver + OMS 2.3.6+	8.5+	YAMAHA USB MIDI Driver + OMS driver + Patch panel	up to 256 output channels; driver patch matrix
2000	Opcode	MIDIport 32 (#post_opcode_midiport32)	USB	2×2 / 32 ch	OMS	8.6/9.x?	Opcode MIDIport32 OMS driver	bus powered; multiple units; USB identity tracking
~2000	Opcode	MIDIport 96 (#post_opcode_midiport96)	USB	6×6 / 96 ch	OMS	8.6/9.x?	Opcode MIDIport96 OMS driver	larger MIDIport family member
2000	Steinberg	USB-2-MIDI (#post_steinberg_usb2midi)	USB	2×2 / 32 ch	vendor Mac driver; OMS-era use	Classic Mac	Steinberg USB-2-MIDI Mac driver	bus powered; bypass/thru mode
2000	Steinberg	MIDEX 8 (#post_steinberg_midex8)	USB	8×8 / 128 ch; Out 8 duplicated	OMS driver; LTB with compatible Steinberg software	8.6/9.x	Steinberg MIDEX 8 Mac/OMS driver	LTB timestamping; period claim ≈300 µs scheduling precision
2000	Midiman	MIDISPORT 2x2 (#post_midisport2x2)	USB	2×2 / 32 ch	OMS vendor driver	8.6/9.x family	Midiman USB MIDISPORT OMS driver	revision caveat: later Anniversary hardware reports conflict
2000	Midiman	MIDISPORT 4x4 (#post_midisport4x4)	USB	4×4 / 64 ch	OMS vendor driver	8.6+	Midiman USB MIDISPORT OMS driver	bus powered; multiple units supported
2000	Midiman	MIDISPORT 8x8/s (#post_midisport8x8)	USB + Mac serial	8×8 / 128 ch	OMS vendor driver	USB 8.6+; serial 7.5+ recommended	MIDISPORT USB OMS + Serial8x8 OMS drivers	SMPTE/MTC; standalone patchbay; separate USB/serial Mac drivers
2000	Roland / Edirol	UM-2 / UM-4 (#post_edirol_um2_um4)	USB	2×2 / 4×4	vendor Classic-Mac MIDI driver	8.5+ period documentation	Roland/Edirol Classic-Mac USB MIDI driver	also sold in SMPU32/SMPU64 lineage
~2000	Roland / Edirol	UM-1 / UM-1S (#post_edirol_um1)	USB	1×1	OMS-era vendor driver	9.x confirmed by forum driver use	Edirol UM-1 Classic-Mac driver	simple cable-style interface
2001	Midiman	MIDISPORT 1x1 (#post_midisport1x1)	USB	1×1	OMS vendor driver	8.6/9.x family	Midiman USB MIDISPORT OMS driver	buyer-guide documented by 2001
2002	Steinberg	MIDEX 3 (#post_steinberg_midex3)	USB	1 In / 3 Out / 48 output ch	OMS 2.3.8+; LTB with compatible Steinberg software	8.6+	Steinberg MIDEX-3 driver; OMS 2.3.8+	bus powered; automatic Thru on In/Out 1
2002	Edirol	UM-550 (#post_edirol_um550)	USB	5×5 / 80 ch	separate OMS + FreeMIDI setup/driver paths	Classic Mac OS	UM-550 OMS / FreeMIDI drivers + settings	hardware patcher; HDMR/FPT
~2001/02	Edirol	UM-880 (#post_edirol_um880)	USB	8×8 / 128 ch	OMS driver 1.0.1 + FreeMIDI driver 1.0.1	Classic Mac OS	UM-880 OMS 1.0.1 / FreeMIDI 1.0.1	larger UM-550 sibling; standalone routing
2002-07	Digidesign	MIDI I/O (#post_digidesign_midiio)	USB	10×10 / 160 ch	OMS; Digidesign Time-Stamping planned/supported in Pro Tools path	9.x	Digidesign MIDI I/O / OMS driver	up to four = 40 ports / 640 ch; programmable hardware Thru
2003-06	MOTU	MIDI Express 128 (#post_motu_express128)	USB	8 In / 8 addr. Out; 9 physical Out	FM + OMS; MOTU USB driver	9.x	MOTU USB MIDI installer + FM/OMS drivers	bus powered; 128 ch
2003-06	MOTU	micro lite (#post_motu_microlite)	USB	5×5 / 80 ch	FM + OMS; MOTU USB driver	9.x	MOTU USB MIDI installer + FM/OMS drivers	bus powered compact interface
?	Yamaha	UX96 (#post_yamaha_ux96)	USB	1×1 DIN + TO TG/INST host port	Yamaha USB-MIDI/OMS family; exact Classic package ?	?	Yamaha model-specific USB-MIDI/OMS package ?	forum confirms direct TO HOST device connection feature
?	Yamaha	UX16 (#post_yamaha_ux16)	USB	1×1	Yamaha USB-MIDI family; exact Classic package ?	?	Yamaha model-specific USB-MIDI/OMS package ?	Classic-era model; retain ? until exact OS9 package/date is recovered
~2005	Roland / Edirol	UM-1EX / UM-2EX / UM-3EX (#post_edirol_ex)	USB	1×1 / 2×2 / 3×3	vendor driver	9.2.2 user-confirmed for UM-1EX; model-specific drivers	Edirol model-specific Classic-Mac USB drivers	late Classic-Mac-compatible edge; verify exact revision before purchase

PCI / internal serial restoration — not MIDI interfaces themselves

Year	Manufacturer	Model	Connection	Ports	MIDI relevance
1999	Keyspan	SX PRO Serial Card (#post_keyspan_sxpro)	PCI → RS-422	4× Mini-DIN-8	1 Mbps/port; manufacturer explicitly advertised support for selected MIDI peripherals
1999/2000	Keyspan	USA-28X / Twin Serial Adapter (#post_keyspan_usa28x)	USB → serial	2× Mini-DIN-8	works with some serial MIDI systems but compatibility is device-specific; forum reports MTP AV better than Studio 5
1999	GeeThree	Stealth Serial Port (#post_stealth)	internal modem slot → RS-422	1× Mini-DIN-8	restores a native-like externally-clockable serial port on supported B&W G3/G4/iMac models; useful for legacy MIDI
1999/2000	MegaWolf	Remus/2 · Romulus/4 · Rufus/8 (#post_megawolf)	PCI → serial	2 / 4 / 8 ports	PCI serial expansion used for legacy MIDI; forum warns some MegaWolf configurations are FreeMIDI-oriented rather than universal OMS replacements

Important bridge warning: USB-to-serial is not automatically equivalent to a real Mac serial port. Emagic specifically states that USB-to-serial adapters such as the Keyspan USB Serial Adapter / Griffin iPort are unsuitable for the Unitor8 serial connection because the required external clocking is absent. Use the Unitor/AMT USB connection instead. Other serial MIDI boxes must be checked individually.

FireWire / mLAN — MIDI transported inside multifunction audio/network hardware

Year	Manufacturer	Model	Host	MIDI	Classic Mac OS	Notes
~2000	Yamaha	mLAN8P (#post_yamaha_mlan8p)	IEEE-1394 / mLAN	MIDI + audio over mLAN; physical MIDI I/O	8.6–9.2.2 forum report; mLAN driver ≤1.04 + mLAN Mixer	first-generation mLAN; not a MIDI-only interface
2004	Yamaha	i88X (#post_yamaha_i88x)	IEEE-1394 S400 / mLAN	mLAN MIDI ports + physical MIDI I/O	9.2; OMS 2.3.8 + mLAN Tools	Yamaha explicitly documents Mac OS 9 for i88X/mLAN16E; MY16-mLAN excluded from OS9

Details

Classic Mac MIDI architecture

USB: Mac OS 9 is not a modern class-compliant USB-MIDI environment. A period device normally needs its manufacturer extension/driver and then OMS, FreeMIDI, or a vendor-specific layer. This explains why a modern class-compliant controller can trigger the Mac’s “look for a driver” behavior instead of simply appearing as a MIDI endpoint.
OMS and FreeMIDI can coexist. MOTU provided an OMS Emulator in FreeMIDI; compatibility was not always identical to native OMS. Conversely, Opcode Studio 4/5 could be used from FreeMIDI through MTP emulation, but some Opcode-specific processing/control was then lost.
Timestamp systems are ecosystem-specific. MOTU MTS, Emagic AMT and Steinberg LTB all improve scheduling by delivering data early with timing information and letting the interface transmit it at the intended instant, but applications must support the respective scheme. Do not label every USB MIDI application “timestamped” merely because the hardware can do it.
Serial interfaces divide into simple 16-channel-per-Mac-port designs and intelligent multi-port boxes. MacOS9Lives users correctly warn that a box with several physical DIN sockets is not automatically a multi-port protocol device; processor/driver support is what creates independently addressable ports over one serial connection.

Sources: MacOS9Lives — generic USB MIDI discussion (https://macos9lives.com/smforum/index.php?topic=3908.0) · Sound On Sound — FreeMIDI & OMS (https://www.soundonsound.com/techniques/motu-freemidi-opcode-oms) · Sound On Sound — timestamped MIDI timing (https://www.soundonsound.com/techniques/identifying-solving-pc-midi-audio-timing-problems) · MacOS9Lives — serial architecture discussion (https://macos9lives.com/smforum/index.php?topic=313.20)

MOTU MIDI Time Piece I — 1990

Period Sound On Sound review identifies it as MOTU’s first hardware: 8×8 MIDI interface/network + SMPTE synchronizer for Macintosh; 128 independently addressable channels.
Two MTPs can be linked on one Mac serial port; using both Macintosh serial ports allowed four units / 32 independent MIDI ports / 512 channels in the original architecture.
The multi-port advantage requires MTP-aware software; non-aware software sees a conventional serial MIDI path.

Sources: SOS Sep 1990 (https://www.muzines.co.uk/articles/motu-midi-time-piece/7287) · Music Technology Jan 1992 (https://www.worldradiohistory.com/UK/Music-Technology/Music-Technology-1992-01-S-OCR.pdf)

MOTU MIDI Time Piece II — 1993

8×8 / 128 channels; adds 128 routing/processing scenes, front-panel editing/LCD and standalone operation.
Period review explicitly compares it with Opcode Studio 5/4 and documents the multi-port MTP architecture.

Source: SOS Feb 1993 (https://www.muzines.co.uk/articles/motu-midi-time-piece-ii/10506)

MOTU MIDI Express — 1993

Period Mac coverage describes a 4×6 multi-port matrix with memories and LTC→MTC/DTLe synchronization. It belongs to the Express branch, not the Timepiece networking branch.

Source: SOS Mar 1993 Apple Notes (https://www.muzines.co.uk/articles/apple-notes/10539)

MOTU FastLane Serial

MacOS9Lives serial overview records the non-USB FastLane as a simple 1-In/3-Out serial interface. Exact first retail date still needs a primary-source lock; retain ~1994 rather than inventing a precise month.

Source: MacOS9Lives serial-interface corpus (https://macos9lives.com/smforum/index.php?topic=313.0)

MOTU MIDI Timepiece AV — serial

Period 1996 MOTU advertising calls it the new MIDI Timepiece for ADAT, Pro Tools and video: MIDI + SMPTE/video genlock + ADAT Sync + word clock + Digidesign SuperClock.
8×8/128-channel Timepiece architecture; networkable within the Timepiece family. MacOS9Lives correspondence with MOTU states the Timepiece line, not Express boxes, is the MOTU Timepiece-network branch.

Sources: Mix Aug 1996 (https://www.worldradiohistory.com/Archive-All-Audio/Mix-Magazine/90s/96/Mix-1996-08.pdf) · MacOS9Lives (https://macos9lives.com/smforum/index.php?topic=313.0)

MOTU micro express — serial

Forum owner report identifies the original Macintosh model as 4-input/6-output MIDI interface, MIDI patchbay and SMPTE-to-MIDI synchronizer connected to the Mac modem/printer serial port. Later FreeMIDI packages include the driver family.

Source: MacOS9Lives — owner report (https://macos9lives.com/smforum/index.php?topic=313.0)

MOTU MIDI Express XT — serial

1996/97 period product generation: 8 inputs, 128 addressable output channels, 9 physical output jacks, SMPTE/MMC and front-panel presets. The later USB XT is a separate host-connection revision.

Sources: MacOS9Lives serial overview (https://macos9lives.com/smforum/index.php?topic=313.0)

MOTU FastLane-USB — 1999

Shipping by Sep 1999. 2×2 / 32 channels; bus powered; Thru operation without computer.
Mac manual: Mac OS 8.6/9; installer supplies MOTU USB Driver, FreeMIDI USB Driver and OMS USB Driver; FreeMIDI and OMS are both supported.
Period Electronic Musician testing documents hardware MIDI Time Stamping support; timestamp benefit depends on compatible software, notably Digital Performer.

Sources: Sweetwater Sep 1999 (https://www.sweetwater.com/insync/motu-fastlane-usb/) · MOTU Mac manual (https://cdn-data.motu.com/manuals/midi/FastLane-USB_User_Guide_Mac.pdf)

MOTU USB rack family — 2000

MIDI Timepiece AV USB, MIDI Express XT USB and micro express moved the established MOTU rack family to USB while retaining model-specific sync/patching functions. Period MacOS9Lives material records Mac OS 8.6+ for MOTU USB MIDI devices.
MOTU’s Mac manual architecture supports mixing multiple MOTU USB MIDI interfaces on one USB system through hubs. MTS is a capability of the USB generation when paired with supporting software, not a universal OMS feature.
micro express=4×6 / 96 channels. Express XT=8 independently addressable output ports with an extra physical output jack. MTP AV=8×8 / 128 channels plus high-end sync.

Sources: MacOS9Lives USB-interface corpus (https://macos9lives.com/smforum/index.php?topic=280.0) · MOTU USB Mac architecture (https://cdn-data.motu.com/manuals/midi/FastLane-USB_User_Guide_Mac.pdf)

MOTU MIDI Express 128 / micro lite — 2003

Both announced/shipping June 2003 with Mac OS 9 and X support: Express 128=8 In / 8 addressable Out (9 physical Out), 128 channels; micro lite=5×5 / 80 channels; both USB bus powered.

Sources: MacMusic 2 Jun 2003 (https://www.macmusic.org/news/view.php/lang/en/id/725/) · MacMusic 20 Jun 2003 (https://www.macmusic.org/news/view.php/lang/en/id/764/)

Opcode Studio 5 — 1991/92

Launch is identified by contemporary MOTU coverage as 1991; detailed SOS review followed Apr 1992. 15 MIDI Ins + 15 Outs = 240 independently addressable channels under OMS/MTP-aware software.
Dedicated 68000 processing allows routing, splitting, transposition, filtering/mapping and stored patches; SMPTE reader/generator; either or both Mac serial ports can be used.
Later firmware/OMS material supports networking multiple Studio 5s; forum/manual evidence records up to six = 1,440 MIDI channels.

Sources: SOS Apr 1992 (https://www.muzines.co.uk/articles/opcode-studio-5/9378) · SOS Feb 1993 (https://www.muzines.co.uk/articles/motu-midi-time-piece-ii/10506) · MacOS9Lives (https://macos9lives.com/smforum/index.php?topic=313.0)

Opcode Studio 3 / Studio 4 — 1992

Period 1992/93 coverage: Studio 3=2-port/32-channel computer interface with 2×6 physical patchbay and SMPTE; Studio 4=8×8/128-channel intelligent interface with the same OMS processing concept as Studio 5.
Studio 4 supports MTP emulation and multiple-unit expansion; MacOS9Lives documentation/manual excerpts record 10 physical Out sockets and up to four units / 512 channels.

Sources: SOS Jan 1993 (https://www.muzines.co.uk/articles/20-20-vision/10471) · MacOS9Lives (https://macos9lives.com/smforum/index.php?topic=313.0)

Opcode Studio 5LX — 1996

15×15 / 240-channel Studio 5 evolution. Forum/manual evidence records 16 MHz 68000, 256K RAM, 128 OMS Studio Patches, standard/fast communication, MTP emulation and networking of up to six units.

Source: MacOS9Lives serial corpus (https://macos9lives.com/smforum/index.php?topic=313.0)

Opcode late serial family — Studio 64X / 64 XTC / 128X

Studio 64X (1997): 64-channel multi-port interface/patchbay/SMPTE unit; four independently addressable port groups, with additional physical Out duplication.
Studio 64 XTC (1998): 64X successor with expanded synchronization. Its 1998 manual is contemporary primary documentation.
Studio 128X (1998): eight addressable input/output ports / 128 channels; manual exposes In 1–8 and Out 1–8 plus sync/control/broadcast endpoints. Period Opcode advertising shows the 8-In/9-physical-Out layout.

Sources: The Mix 1998 buyer guide (https://www.worldradiohistory.com/UK//The-Mix/The-Mix-UK-1998-05-S-OCR.pdf) · 64 XTC manual (https://manualzz.com/doc/7197227/opcode-systems--inc.-studio-64-xtc-midi-interface-user-ma...) · Studio 128X manual (https://oldschooldaw.com/opcode/uploads/PDF/Studio_128X.pdf)

Opcode MIDIport USB family

MIDIport 32=2×2/32 channels, USB bus power, OMS and persistent USB identity intended to prevent port/device renumbering between boots. Multiple units supported.
MIDIport 96=6×6/96-channel larger sibling appearing in period Opcode product material. Exact first-ship date remains less secure than MIDIport32; retain ~2000.

Source: MacOS9Lives USB corpus with archived Opcode material (https://macos9lives.com/smforum/index.php?topic=280.0)

Emagic Unitor8 — 1998

Period Dec 1998 review: 8 inputs/8 outputs; RS-422 Mac serial; RS-232 PC; OMS support; FreeMIDI emulation; fast up to 4 MHz vs normal 1 MHz communication; LTC/VITC; standalone patches.
Later shared Unitor/AMT documentation establishes Mac serial operation from OS 7.5.3+ and stacking up to eight interfaces per serial chain.

Sources: The Mix Dec 1998 (https://www.worldradiohistory.com/UK/The-Mix/The-Mix-UK-1998-12-S-OCR.pdf) · shared Unitor manual (https://manualzilla.com/doc/6908413/user-manual-unitor-8)

Emagic AMT8 — 2000

8×8; seven pairs rear + port 8 on front; USB + RS-422 Mac serial + RS-232 PC; patch mode. Unlike Unitor it omits the full LTC/VITC sync hardware.
AMT sends time-qualified MIDI ahead of schedule for interface-timed output when used with compatible software such as Logic. OMS/FreeMIDI paths remain available but AMT should not be assumed in non-AMT applications.

Source: SOS Jan 2000 (https://www.soundonsound.com/reviews/emagic-amt8)

Emagic Unitor8 MkII — 2000

Electronic Musician Apr 2001 explicitly says Emagic introduced the MkII “last year,” establishing 2000 rather than 2001 as the introduction year.
8×8/128ch; USB + RS-422 serial; AMT; professional LTC/VITC sync. Shared technical spec: serial Mac OS 7.5.3+; USB Mac OS 9.0.4+.
Dedicated OMS driver is important: the generic OMS MTP driver sees only the first Unitor-family unit and runs it at slow 1 MHz; the Emagic OMS driver supports the chain/full feature set. Unitor8 MkII, AMT8 and original Unitor8 may be stacked in mixed chains.
Do not use a generic USB-to-serial adapter as a substitute for the Unitor serial port; Emagic documents the missing external-clock problem.

Sources: Electronic Musician Apr 2001 (https://www.worldradiohistory.com/Archive-All-Music/Electronic-Musician/2001/Electronic-Musician-2001-04.pdf) · Unitor8/AMT8 manual (https://manualzilla.com/doc/6908413/user-manual-unitor-8)

Emagic MT4 — 2000

Period July 2000 review: USB, 2 MIDI In / 4 MIDI Out, Mac OMS/Logic support and standalone patchbay operation. It is the compact member below AMT8/Unitor8.

Source: MEMI 25 Jul 2000 (https://memi.de/vintage-lab/emagic-mt4/)

Steinberg USB-2-MIDI — 2000

Period Electronic Musician Sep 2000: 2×2 cross-platform USB, bus powered, with bypass mode. MacOS9Lives users later reported hardware/driver kinship with MIDISPORT 2x2; treat that as a forum report, not as proof that every revision is electrically identical.

Sources: Electronic Musician Sep 2000 (https://www.worldradiohistory.com/Archive-All-Music/Electronic-Musician/2000/Electronic-Musician-2000-09.pdf)

Steinberg MIDEX 8 — 2000

8 independent MIDI input/output pairs, 128 channels; output 8 is physically duplicated. USB host connection.
LTB=Linear Time Base: timestamped events are sent early and emitted by the interface at the intended song time. Period launch material advertised ≈300 µs scheduling precision; this requires compatible Steinberg software and must not be confused with generic OMS timing.
Announced/shown in 2000; late-2000 reports show availability timing varying by platform/market. The hardware generation belongs in 2000 rather than being blindly dated 2001 from later driver threads.

Sources: Electronic Musician Sep 2000 (https://www.worldradiohistory.com/Archive-All-Music/Electronic-Musician/2000/Electronic-Musician-2000-09.pdf) · MIDEX 8 manual (https://www.handelima.net/studiogear/manuals/Steinberg/STEINBERG%20MIDEX8/Midex8OperationManual.pdf) · period Steinberg announcement (https://www.sweetwater.com/insync/steinberg-cubase-50-midex-8/)

Steinberg MIDEX 3 — 2002 era

1 input + 3 independent outputs = 48 output channels; USB bus powered; automatic MIDI Thru on In/Out 1 when software is not using the interface.
Manual: Mac OS 8.6+ and OMS 2.3.8+; LTB available with compatible Steinberg applications.

Source: MIDEX 3 operation manual (https://manualmachine.com/steinberger/midex3/6489590-operation-manual/)

Midiman/M-Audio MIDISPORT family

MIDISPORT 2x2: official M-Audio retrospective says introduced in 2000. Do not use the June 1999 date of an archived Midiman USB driver as proof that the 2x2 itself was already shipping then.
4x4: 4×4/64 channels, USB bus powered; manual requires Mac OS 8.6+ and OMS.
8x8/s: 8 independent In + 8 Out/128ch; USB and legacy Mac serial; SMPTE/MTC + standalone patchbay. Manual: USB Mac OS 8.6+; serial Mac OS 7.5+ recommended; OMS required. USB and serial use separate Mac driver paths.
1x1: present in 2001 buyer-guide documentation; same general MIDISPORT Classic-Mac driver lineage.
Revision warning: MacOS9Lives contains conflicting reports for the later green/black “Anniversary” 2x2: one MDD user report says it works; another owner reports failure with the OS9 package; another forum report says the Anniversary hardware changed during production. Therefore “MIDISPORT 2x2” is not enough identification when buying for OS9 — photograph/revision matters.

Sources: M-Audio 2x2 history (https://www.m-audio.com/legacy/midisport-2x2-anniversary-edition.html) · MIDISPORT 4x4 manual (https://manualzilla.com/doc/5689800/midisport-4x4%E2%84%A2-manual) · MIDISPORT 8x8/s manual (https://manualzilla.com/doc/7375115/m-audio-midisport-8x8-user-guide) · MacOS9Lives revision/driver reports (https://macos9lives.com/smforum/index.php?topic=280.20)

Yamaha UX256 — 2000

Hardware: six MIDI IN/OUT pairs + two TO TG serial-host ports. The driver exposes up to 16 output ports / 256 output channels and 8 input ports / 128 input channels because each TO TG port can address multiple logical ports on compatible Yamaha “TO HOST” devices.
Mac manual: Mac OS 8.5+ on USB iMac/G3/G4; OMS 2.3.6+; installs YAMAHA USB MIDI Driver, YAMAHA USB MIDI OMS Driver and USB MIDI Patch control panel.
Multiple UX256s are supported through USB hubs; the manual documents up to 32 units as a theoretical supported configuration subject to the operating environment.

Sources: Yamaha UX256 manual (https://usa.yamaha.com/files/download/other_assets/1/319451/ux256_1.pdf)

Yamaha UX96 / UX16

UX96 forum evidence is useful because its TO TG/INST connector can directly attach MIDI devices equipped with the older serial “TO HOST” interface. This is not just an extra DIN MIDI port.
Yamaha still indexes period manuals for UX96 and UX16, but this pass did not recover a sufficiently explicit model-specific Classic-Mac OS driver requirement to remove the ? from those rows. Do not inherit the UX256 OS floor by assumption.

Sources: MacOS9Lives — UX96 addition (https://macos9lives.com/smforum/index.php?topic=280.0) · Yamaha manual archive (https://usa.yamaha.com/support/manuals/index.html?c=music_production&k=&l=en&p=22)

Roland / Edirol early USB family — UM-1 / UM-2 / UM-4

Period Electronic Musician Sep 2000 describes UM-2/SMPU32 as 2×2 and UM-4/SMPU64 as 4×4 bus-powered USB interfaces. Contemporary guides place them in the Mac OS 8.5 era.
UM-1/UM-1S is the 1×1 cable-interface branch. MacOS9Lives preserves installer troubleshooting and successful OS9 use; exact revision/driver packaging matters.

Sources: Electronic Musician Sep 2000 (https://www.worldradiohistory.com/Archive-All-Music/Electronic-Musician/2000/Electronic-Musician-2000-09.pdf) · MacOS9Lives USB corpus (https://macos9lives.com/smforum/index.php?topic=280.0)

Edirol UM-550 / UM-880

UM-550=5×5/80ch USB interface + standalone hardware patcher. UM-880=8×8 larger sibling. Roland’s surviving UM-880 support page still lists both “FreeMIDI Driver Version 1.0.1 for Macintosh” and “OMS Driver Version 1.0.1 for Macintosh.”
Shared owner documentation has separate Classic-Mac setup paths for OMS and FreeMIDI; do not treat one settings file as interchangeable with the other.

Sources: Roland UM-550 (https://www.roland.com/us/products/um-550/) · Roland UM-880 driver archive (https://www.roland.com/us/support/by_product/um-880/) · UM-550/880 manual (https://www.scribd.com/document/364503570/EDIROL-UM-550-880-Owners-s-Manual)

Edirol UM-xEX late USB family

MacOS9Lives retains OS9-era driver/user evidence for UM-1EX, UM-2EX and UM-3EX. UM-1EX has a direct 9.2.2 success report; keep model/revision-specific driver packages with the hardware rather than assuming a generic Roland USB-MIDI driver.

Source: MacOS9Lives USB corpus (https://macos9lives.com/smforum/index.php?topic=280.20)

Digidesign MIDI I/O — 2002

Shipping July 2002: 10 MIDI inputs + 10 outputs / 160 channels; USB powered; programmable hardware Thru; OMS compatible outside Pro Tools as well.
Up to four units may be attached for 40 I/O ports / 640 channels. Digidesign announced its own Time-Stamping path for improved Pro Tools timing.

Sources: MacMusic Jul 2002 (https://www.macmusic.org/news/view.php/lang/en/id/84/) · Sweetwater Sep 2002 (https://www.sweetwater.com/insync/digidesign-midi-o/)

Keyspan serial restoration

SX PRO (1999): four RS-422 Mini-DIN-8 ports on PCI; up to 1 Mbps each; Keyspan explicitly advertised support for selected MIDI peripherals. Macworld later catalogued it as a four-port PCI-to-serial solution for PCI Macs.
USA-28X/Twin Serial: USB-to-two-serial bridge. MacOS9Lives preserves driver v1.9 and user tests: MTP AV can work, while Studio 5 behavior is reported as spotty. Treat it as a compatibility matrix item, not a universal “serial port replacement.”

Sources: Keyspan 1999 press release (https://www.penbasedcomputing.com/timeline/keyspan-introduces-new-pci-serial-card-and-a-usb-adapter-for-palm-pilot/) · Macworld UK Jul 2000 (https://www.vintageapplemac.com/files/misc/MacWorld_UK_Jul_2000.pdf) · MacOS9Lives USA-28X reports (https://www.macos9lives.com/smforum/index.php?topic=2446.0)

GeeThree Stealth Serial Port

Internal modem-slot adapter restoring an RS-422 Mini-DIN-8 serial port on supported B&W G3, early G4 and some iMac systems. Period coverage specifically notes support for externally clocked serial peripherals such as MIDI devices and existing serial drivers/Comm Toolbox.
It is not a PCI card and must not be lumped into the Keyspan/MegaWolf PCI group.

Sources: ATPM Aug 2000 (https://www.atpm.com/6.08/stealth.shtml) · TidBITS Mar 2000 (https://tidbits.com/2000/03/06/have-your-serial-and-eat-it-too/)

MegaWolf PCI serial family

Macworld Jul 2000 catalogues Remus/2=2 ports, Romulus/4=4 ports, Rufus/8=8 ports, all PCI-to-serial products. These are host expansion devices used to attach legacy serial MIDI boxes rather than MIDI interfaces themselves.
MacOS9Lives contains both useful MIDI use reports and extension/OMS-vs-FreeMIDI caveats. Preserve the specific card driver with the hardware; do not assume every MegaWolf driver exposes an OMS-compatible “native Mac port” in the same way.

Sources: Macworld UK Jul 2000 (https://www.vintageapplemac.com/files/misc/MacWorld_UK_Jul_2000.pdf) · MacOS9Lives Board 42 corpus (https://macos9lives.com/smforum/index.php?board=42.0)

Yamaha mLAN8P

MacOS9Lives user documentation reports Mac OS 8.6–9.2.2 with early mLAN driver 1.04-or-earlier plus mLAN Mixer from the original CD. Because this is first-generation mLAN and the exact surviving package is difficult to recover, keep the driver version paired with the report rather than generalizing from later Yamaha mLAN Tools.

Source: MacOS9Lives — Audio Interfaces with MIDI I/O (https://macos9lives.com/smforum/index.php?topic=362.0)

Yamaha i88X / mLAN16E — Mac OS 9 mLAN

Yamaha explicitly documents Mac OS 9 support for i88X and mLAN16E; MY16-mLAN is explicitly excluded from Mac OS 9 in the same guide.
Mac OS 9.2; built-in S400 FireWire; installs mLAN Tools / Auto Connector / Graphic Patchbay plus OMS 2.3.8. OMS is required for MIDI/remote-control data over the mLAN network.

Source: Yamaha i88X/mLAN16E Tools installation guide (https://usa.yamaha.com/files/download/other_assets/4/328384/mlane2.pdf)

WIP

Steinberg MicroMIDI
Roland Super MPU64 USB
ESI MIDI products
Orange Micro Grappler+ / other PCI serial cards
RTP-MIDI/network MIDI
Audio interfaces with a MIDI DIN port