Hacking the Roland HD-1

I purchased a used Roland HD-1 drum kit after reading some of the reviews. They pointed out that the HD-1 has three weaknesses: 1) there are only 10 drum kits defined, with only 2 kits that are really useful, and with no ability to redefine the existing kits or define new ones; 2) the kick drum pedal does not feel realistic; and 3) the drum and cymbal pads have only one sensor zone.

There is an article here in which greydog describes how to use a Roland TD-3 to extend the voices for the HD-1. You run a MIDI cable from the output of the HD-1 to the input of the TD-3, after which you have access to all of the voices and kits in the TD-3, including reassignment of voices, changing relative loudness of each voice, and stereo voice panning. This works well, but you are still stuck with the HD-1 kick pedal.

The video here, towards the end, shows how to modify the springs in the HD-1 kick pedal to stiffen it up, but that did not seem like it would be enough. I build a wooden contraption to simulate the kick drum, and attached a regular kick pedal to the “drum”:

The kick input to the HD-1 does not accept a piezo signal: it will not trigger with that kind of input.  I discovered, by accident, that it will trigger if you just short the two signal lines together.  So, my original plan was to put a momentary contact push button switch where the beater hits the wooden panel, countersunk so that the beater just barely “clicked” the switch, and trigger the HD-1’s kick input that way.  I came across a free practice pad that had been converted into a DIY drum pad, and mounted that pad where I had intended to mount the switch. The only problem was how to get that piezo signal to trigger the kick drum.  By connecting the new DIY kick drum sensor directly into the kick input of the TD-3, I was able to get the best of both worlds.  I now have all of the HD-1 drums triggering the TD-3 sounds, and also have the new kick pedal triggering the TD-3 kick sound.  As a side benefit, I actually have two kick drums now, one on the HD-1 and one on the TD-3.


20 Responses to “Hacking the Roland HD-1”

  1. phil Says:

    So do you mean that if I get a piezo (like kd8) kick I can get it to replace my hd1 kick?
    what do you mean by ‘short the two signal lines’?
    do you mean sold them together?

  2. jonbondy Says:


    No, unfortunately you cannot use a piezo to replace the HD-1 kick, because the HD-1 uses resistive sensors for the HD-1 kick, and the piezo is not resistive. I am using a piezo kick, but only by plugging it into the TD-3, which can accept a piezo kick sensor, and not the HD-1.

    The HD-1 kick is triggered when the resistance between the two HD-1 signal lines drops to zero. If you unplug the cable from the HD-1 kick and use a screw driver to connect the two bits of metal at the end of the 1/4″ plug, you will hear the kick drum sound. That is what I meant by “short the two signal lines”.

    If you could replace that screw driver with a [momentary, single pole, single throw, normally open] push button switch, every time you pushed the switch, it would trigger the kick, by momentarily shorting the two lines together. You would lose the ability to modulate the intensity of the sound with this approach (it would always sound maximally loud). What I intended to do was mount that switch on the wooden contraption that I built, recessed so that the kick beater just barely pushed the switch button in, so as to prevent the kick beater from destroying the push button switch.

    Make more sense?

  3. Vangelo Says:

    I actually did a mod to the bass pedal to trigger my new TD4 module.. I removed the rubber hammer & bought a 32mm piezo sensor. I used double-sided tape & stuck this sensor on top of the existing resistive one & ran the wires to the output jack.
    I put 2 layers of 5mm neoprene rubber (adhesive one one side) over the sensor which gives perfect triggering from the existing metal hammer under the pedal. I also put a few layers of the neoprene between the base of the pedal & plastic cowling to prevent the two hitting each other. I later susbtituted this with a pair of rubber feet the appropriate height to make a neater job.

    All works very well. I also converted the snare to twin trigger to activate the rim. This was very easy to do as the space exists for a 32mm piezo sensor under the existing one. The output jack is already stereo & just needs to be connected.

    • jonbondy Says:

      Very cool way to convert your HD-1 hardware to trigger the TD-4!

      • Vangelo Says:

        I didnt set out to do it that way. Originally I thought I would need a proper bass pedal/trigger. I temporarily placed the sensor under to rubber of the pedal to see if it would trigger the TD4. It worked but the rubber contact made rustling noises & it wasnt a clean hit. Then I took the rubber out & placed a couple layers of neoprene so the sensor would contact the metal hammer & it worked perfect!

      • Dave Says:

        Vangelo, did it retain the velocity sensitivity, or is the kick now just one level sound no matter how hard or soft you kick?

  4. Johnny Says:

    … And if I connect a tom pad (I use only one in my setup), it gonna work? Thank you Jon! Greetings from Brazil!

  5. jonbondy Says:

    Johnny: connect a tom pad to where? Connecting a tom pad to the kick input of the HD-1 is not likely to work. Connecting a tom pad to a TD-3 should work.

  6. Diogo Borges Says:

    I’m banging my head.
    I found this solution will test.
    I think it works

  7. Ralph Says:

    Hi, i would use an hd1 tom as kick pad to use a regular bass pedal instead of hd1 pedals. Could you explain me how do it?thanks

    • jonbondy Says:

      You would have to remove the tom from the main assembly and fabricate a way to attach the pedal. It would be fairly simple for someone with a shop, and shop experience, but pretty difficult for someone without this experience. I have no idea what your skill level is.

      • Ralph Says:

        Thanks for your reply, i guess it will be attached to the two central tube, i don’t know how to do it electronically 😁

  8. jonbondy Says:

    You would just leave the tom attached to the controller in the usual way. No change at all. Of course the kick would sound like a tom. There is no easy way to tell the controller to have the tom signal sound like a kick.

    • Ralph Says:

      Well that’s would be really awful, a kick pad that sounds as a tom 🙂
      Anyway, I’m trying to understand how modify tom to insert kick cable in it

  9. Martyn Edwards Says:

    Hi, I appreciate this is a VERY old post but I have been searching the web looking for posts regarding Roland HD-1 and Roland KD8 kick drum compatibility (which of course are not compatible!) – I have worked out a way of using parts from the HD1 kick pedal and transferring them to the KD8 to make it work with the HD1 brain. If you are reading this and interested to know more get in touch!

    • Alex Vozzella Says:

      HI Martyn,
      Glad I came across your post, and with great timing. I have a Roland Hd-1 and just recently bought a Roland Kd-9 kick drum that is not compatible with the Hd-1 (wish I knew before I bought it!). Is there a way to make the Kd-9 kick pad work with the Hd-1 brain? I believe the Kd-9 and Kd-8 are similar so I’m hoping your method works for me as well.

      • Martyn Edwards Says:

        Hi Alex
        There is a way but it would involve taking your HD1 and KD9 kick drums apart, is that something you’re confident in doing? Wouldn’t want you to end up with neither working!
        Let me know and I’ll try work out how to post photos.


      • Douglas Veiga Says:

        Hi Martyn!
        I replaced the HD1 bass drum pedal with a DDrum pad, which I placed the original HD-1 pressure sensor inside, resting against the original pad rubber. This way I can use this pad in HD1 and DDrum. Keep piezo and sensor nearby and with individual plugs.

      • Martyn Edwards Says:

        Hi Douglas
        I pleased to hear you found a solution that works for you.

        All the best.


Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google+ photo

You are commenting using your Google+ account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )


Connecting to %s

%d bloggers like this: