Yamaha YM2414 (OPZ)

• 8 waveforms (but they’re different from the OPL ones)
• Per-channel (possibly) linear volume control separate from TL
• Increased multiplier precision (in 1/16ths)
• 4-step envelope generator shift (minimum TL)
• Another LFO
• No per-operator key on/off
• Fixed frequency mode per operator (kind of like OPN family’s extended channel mode but with a bit less precision and for all 8 channels)
• “Reverb” effect (actually extends release)

• Furnace works with register writes rather than MIDI commands
• The MIDI protocol is slow (would not be enough).
• The TX81Z is very slow to process a note on/off or parameter change event.
• The TL range has been reduced to 0-99, but the chip goes from 0-127.

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Effects

• 10xx: set noise frequency of channel 8 operator 4. 00 disables noise while 01 to 20 enable it.
• 11xx: set feedback of channel.
• 12xx: set operator 1 level.
• 13xx: set operator 2 level.
• 14xx: set operator 3 level.
• 15xx: set operator 4 level.
• 16xy: set multiplier of operator.
  • x is the operator (1-4).
  • y is the new MULT value.
• 17xx: set LFO speed.
• 18xx: set LFO waveform. xx may be one of the following:
  • 00: saw
  • 01: square
  • 02: triangle
  • 03: noise
• 19xx: set attack of all operators.
• 1Axx: set attack of operator 1.
• 1Bxx: set attack of operator 2.
• 1Cxx: set attack of operator 3.
• 1Dxx: set attack of operator 4.
• 1Exx: set LFO AM depth.
• 1Fxx: set LFO PM depth.
• 24xx: set LFO 2 speed.
• 25xx: set LFO 2 waveform. xx may be one of the following:
  • 00: saw
  • 01: square
  • 02: triangle
  • 03: noise
• 26xx: set LFO 2 AM depth.
• 27xx: set LFO 2 PM depth.
• 28xy: set reverb of operator.
  • x is the operator (1-4). A value of 0 means “all operators”.
  • y is the value.
• 2Axy: set waveform of operator.
  • x is the operator (1-4). A value of 0 means “all operators”.
  • y is the value.
• 2Bxy: set EG shift of operator.
  • x is the operator (1-4). A value of 0 means “all operators”.
  • y is the value.
• 2Cxy: set fine multiplier of operator.
  • x is the operator (1-4). A value of 0 means “all operators”.
  • y is the value.
• 2Fxx: enable envelope hard reset.
  • This works by inserting a quick release and tiny delay before a new note.
• 3xyy: set fixed frequency of operator 1/2.
  • x is the block (0-7 for operator 1; 8-F for operator 2).
  • y is the frequency. Fixed frequency mode will be disabled if this is less than 8.
  • The actual frequency is: y*(2^x).
• 4xyy: set fixed frequency of operator 3/4.
  • x is the block (0-7 for operator 3; 8-F for operator 4).
  • y is the frequency. Fixed frequency mode will be disabled if this is less than 8.
  • The actual frequency is: y*(2^x).
• 50xy: set AM of operator.
  • x is the operator (1-4). A value of 0 means “all operators”.
  • y determines whether AM is on.
• 51xy: set SL of operator.
  • x is the operator (1-4). A value of 0 means “all operators”.
  • y is the value.
• 52xy: set RR of operator.
  • x is the operator (1-4). A value of 0 means “all operators”.
  • y is the value.
• 53xy: set DT of operator.
  • x is the operator (1-4). A value of 0 means “all operators”.
  • y is the value:
    • 0: +0
    • 1: +1
    • 2: +2
    • 3: +3
    • 4: -0
    • 5: -3
    • 6: -2
    • 7: -1
• 54xy: set RS of operator.
  • x is the operator (1-4). A value of 0 means “all operators”.
  • y is the value.
• 55xy: set DT2 of operator.
  • x is the operator (1-4). A value of 0 means “all operators”.
  • y is the value.
• 56xx: set DR of all operators.
• 57xx: set DR of operator 1.
• 58xx: set DR of operator 2.
• 59xx: set DR of operator 3.
• 5Axx: set DR of operator 4.
• 5Bxx: set D2R/SR of all operators.
• 5Cxx: set D2R/SR of operator 1.
• 5Dxx: set D2R/SR of operator 2.
• 5Exx: set D2R/SR of operator 3.
• 5Fxx: set D2R/SR of operator 4.
• 61xx: set algorithm (0 to 7).
• 62xx: set LFO FM depth (0 to 7).
• 63xx: set LFO AM depth (0 to 3).
• 64xx: set LFO2 FM depth (0 to 7).
• 65xx: set LFO2 AM depth (0 to 3).

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Instrument Editor

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Chip Configuration

• Pseudo-PAL: Run the chip on a PAL clock. Such a configuration has never been used in hardware.
• Broken pitch macro/slides: Due to an oversight, pitch slides were twice as fast in older versions of Furnace. This option exists for compatibility.