Deep FM bass on Roland JD/JV/XV series


Compatibility: JV-80 and up

Although Super JV/JD have the FXM section that is based on a frequency modulation, it is actually quite limited terms of real FM sounds – it is more oriented towards spicing the sound with a specific character (or making it more ‘wild’ as Roland manual says). For real FM sounds we must look elsewhere.

Super JV/JD is not an FM synth, but it has a nice LFO that can run pretty fast, and with a little experience in real FM programming it is not hard to recreate some basic FM sounds. Please keep in mind that we talk about really basic FM sounds created from only two operators (Yamaha DX-7 for example has 6 operators). And even those ”two operators” we will build on Super JV/JD are very primitive, compared to any real FM synth.

Deep FM Bass
We will create one of the deepest basses ever, that goes subsonic, much below 20 Hz. I first built this bass on the Yamaha SY-77 some long time ago, but since it requires only two operators, i recently came to idea to try to emulate it on the JV/JD synth. Ok, it will not sound as powerful as the real one, but it will demonstrate that it is possible to do some primitive FM on the JD, JV, XP, XV synth line.

We will be using two operators. The WG (tone generator) will be the carrier, and LFO will be the modulator. Sound will be made by the classic two point down ramp envelope applied on the modulator – that is, the modulator level starts loud and then fades away. On the real FM synth you would do that with an envelope. Unfortunately on the Super JV you can’t apply an envelope (ENV) to modulate the level of LFO, so on the first sight it appears our FM sound won’t function properly. But there is a workaround for that issue. We will build the envelope on the LFO using ramp, which Roland just calls LFO Fade In/Out function. In other words you got simple two point envelope that can be applied to LFO – i know it is primitive, but better something than nothing. With this ramp you can create dozens of bells and metallic percussion, if used the right way. Here is detailed procedure:

  • Initialize the sound
  • Enable T1, disable all other tones
  • Go to Control and set Key Assign to MONO
  • Set WG1 to Sine
  • Go to Pitch, set Coarse Tune to -12
  • Go to LFO and set it to SAW-DW
  • Jump to TVA1 and disable velocity (V-Sens=0)

You probably noticed that we used Saw wave in the LFO instead of Sine wave. We had to use the saw to add more punch to the sound, because JV is not a real FM synth, and with a sine wave LFO, the sound becomes too muddy in the low C1-C2 region. However, later you can try switching LFO to sine wave and try C2-C4 notes that will sound better with it. You will also use sine wave in the LFO for all metallic and bell sounds. Or to be precise, you should use sine wave LFO in almost all FM sounds, except those in low pitch range where you will use SAW-DW wave to compensate the lack of punch.

  • Within LFO set Depth Pitch: +50
  • Set Fade Mode: ON-OUT (this is our ramp down envelope)
  • Go to TVA and make a short sound using following parameters
  • Time: 0 20 42 42
  • Level: 127 127 0
  • Now hit A1 and C2 few times
  • For shorter and more distinctive bass set time to: 0 10 42 42

Although nature commences with reason and ends in experience it is necessary for us to do the opposite, that is to commence with experience and from this to proceed to investigate the reason. – Leonardo da Vinci

Comments (8)

  1. Gary

    Going to give this a go on my XP30 tonight I think. So we can “do” FM (albeit very simply) as well as PWM. If only there was a way to simulate osc sync on an unexpanded XP30 (The vintage cards are rarer than hen’s teeth it seems).

  2. lok

    Call me an idiot but i cannot find the sine waveform in the 2080.Finded other basic ones in the GM bank and in PRB i guess like saw, Juno/Moog squares and saws but that’s about it.

    Where it is hided please ? Thanks

    Loving the JV so far, synthesis engine is quite deep and it sounds great. You’re partly responsible of the swap i did: my Minibrute for the JV2080. 😉

    • Lok

      Finally find the patch! Sinusoid Rave bank PR-B 45

      I finded the patch list but not the waveform shortcuts list yet. Have to do it.

      • Don Solaris

        LOL! Wut? Don’t tell me you wasted 2 days looking for something instead of spending 25 minutes to read the manual from start to finish. In fact i found your commend by coincidence, otherwise you could have waited for weeks for the answer.

        • Lok

          Come on! I digged the manual from day minus one, even before getting it, as usual. Yet shit happens, don’t bitch on me.

          This LFO setting does not work for me either, I don’t get that big FM sound with the ON/OUT setting, no modulation are happening at all, i have to switch to other Ramp settings it seems to be able to hear some modulations. I don’t know what’s wrong with my patch or your text.

  3. Martin

    Lok, you’ve got it wrong. You don’t have to tweak an existing preset patch, as the sinusoidal thing you mentioned..You must create a new patch. So if you take a look at your manual, not in the patches but in the tones..(INT-A and INT-B). The sine tone is what you’re looking for, it’s in the INT-B..RTFM About how to make a new patch from the scratch..You’ll get it, i’m sure.

  4. Luke

    I think for XPs since they don’t have a SAW-DW, you need to set SAW, ON-OUT, and Pitch to _minus_ 50 to get the down ramp, is that correct? Or is there a better way?

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