| Year | Manufacturer | Model | Host connection | MIDI I/O | OMS / FreeMIDI / timing | Classic Mac OS | Driver | Notes |
| 1990 | MOTU | MIDI Time Piece I | 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 | 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 | 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 | 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 | 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 | 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 | 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 | 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 | 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 | 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 | 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 | 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 | 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 | 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 | 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 | 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 | 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 | 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 | 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 | 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 | 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 | 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 | 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 | 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 | USB | 6×6 / 96 ch | OMS | 8.6/9.x? | Opcode MIDIport96 OMS driver | larger MIDIport family member |
| 2000 | Steinberg | USB-2-MIDI | 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 | 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 | 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 | 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 | 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 | 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 | 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 | 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 | 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 | 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 | 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 | 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 | 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 | 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 | 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 | 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 | 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 |
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.