Troubleshooting Hotspot Suppression

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Troubleshooting Hotspot Suppression

Post by Rob »

Hotspot suppression is designed to work with commercially available drums. It relies on having a clean signal from a center mounted piezo on a mesh drum pad. If you are trying to use it with DIY designs or A-E conversion kits, you may run into issues if the signal coming from you drum is not clean enough.

Common problems that will prevent hotspot suppression from working properly:
  • The signal is clipping the eDRUMin input.
  • The ‘amount’ control is set too high.
  • Type of Mesh Head
  • The tension of your drum head is too stiff, too loose or uneven.
  • The construction of your pad is not up to par.
If the signal from your pad is clipping the eDRUMin input, you are going to run into issues. You can tell if the signal is clipping if the GAIN slider is set to 1 (the lowest value) and the VU meter maxes out. If this is happening, you need to mechanically reduce the strength of the signal from your pad. Here are some suggestions:
  • Don’t use 35mm piezos. 27mm tend to work best.
  • Lower the height of your sensor / cone so that it isn’t pressing too hard into the mesh head.
  • Use a softer cone.
The Amount control is set too high
As the device is processing hotspot suppression, if it runs into a situation where the amount of suppression is calculated to be more than 75% of the raw velocity, it will NOT suppress the velocity at all. This behavior prevents the device from completely swallowing a hit. This can happen if you set the AMOUNT control too high. Always start adjusting the hotspot suppression controls with AMOUNT set to zero. Find the correct THRESH setting first and slowly increase the AMOUNT control.

Type of Mesh Head
2-Ply heads are recommended over 3-ply heads, which tend to rattle more and introduce unwanted high frequency content which interferes with hotspot suppression and positional sensing.

Drum Head Tension
If the tension of your mesh head is too loose, too tight, or uneven, you will run into problems. Treat tensioning of your drum head the same way you would an acoustic, but keep in mind that a mesh head will never be as stiff as an acoustic head.

Proper Construction
Rattling screws, flapping wires, unsoldered connections, structures that are loose or secured with tape are all recipes for poor performance. All these mentioned issues will add unwanted vibrations (noise) into the signal and prevent hotspot suppression from working properly. Adding dampening is another way to keep the signal going into your sensors as clean as possible.

If users have suggestions for good A-E trigger hardware, please reply to this thread.

If after ensuring all your build quality issues are taken care of, you can contact me via technical support and we can take a closer look at what the problem is.
AKA Wayne
Posts: 255
Joined: Thu Dec 26, 2019 6:12 pm

Re: Troubleshooting Hotspot Suppression

Post by AKA Wayne »

Rob. Your support and effort in helping the community you have created continues to blow me away. Your dedication is amazing. Thanks so much for this!
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