Hall Effect retrofitted hi-hat stand splash question

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dsteinschneider
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Hall Effect retrofitted hi-hat stand splash question

Post by dsteinschneider »

The triggering from open to closed is now very smooth and linear and the hi-hat has never played better in SD3 since 2.3.1 build 13. I took advice of another forum member and chose the SD3 Library default for the hi-hat preset (not e-drum one) and pass through in the settings e-drums hi-hat tab. The travel is 1.8cm - the pair of magnets travel up and down with the rod and end up with their tip just even with the sensor.

I don't play splashes with my foot much so the above improvements take priority but I'm curious why it's harder to trigger a splash now - any ideas on why would be appreciated.
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Rob
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Re: Hall Effect retrofitted hi-hat stand splash question

Post by Rob »

There is a control for adjusting the splash sensitivity. Is that not working for you?
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dsteinschneider
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Re: Hall Effect retrofitted hi-hat stand splash question

Post by dsteinschneider »

I can trigger a splash only if I very gently press and quickly release the pedal. The white line in the splash control normally flatlines instead of going back up quickly when I release the pedal quickly.
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Rob
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Re: Hall Effect retrofitted hi-hat stand splash question

Post by Rob »

It could be a number of issues.
1. Try recalibrating the hihat pedal.
2. Make sure the pedal xTalk control is set high enough.
3. Make sure your hall sensor continues to register voltage changes for the whole range of your pedal, which may require you to adjust the position of the magnet.
Mr_Bluesguy
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Re: Hall Effect retrofitted hi-hat stand splash question

Post by Mr_Bluesguy »

There is another possibility to explore here. If I've understood your description correctly, the rod magnet is VERY close to the sensor at full closure. As I've described in a previous post, that situation can actually be counterproductive. A hall sensor by design is capable of outputting max voltage at a given magnetic field strength. Even when the field strength is exceeded, (either by too strong of a magnet or to little gap between magnet and sensor), there will be no further increase in voltage output. So you actually end up wasting available stroke just getting the magnet far enough away to allow output voltage to decrease. This was actually a large portion of the problem I had when I started that thread. I would be really interested to see if this is affecting your ability to produce natural splashes. If you try it, let me know how it turns out.
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dsteinschneider
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Re: Hall Effect retrofitted hi-hat stand splash question

Post by dsteinschneider »

@Mr_Bluesguy - your suggestion led me to move the sensor down which fixed the issue. I also decided after playing with 1.8cm of travel for a week to go back to the 2.5cm of travel I was at before. It's splashing now every time I release the pedal quickly. Really playing perfectly - I took photos and marked everything to make sure I can place sensor where it belongs and set the travel.

Thanks
Mr_Bluesguy
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Re: Hall Effect retrofitted hi-hat stand splash question

Post by Mr_Bluesguy »

@ dsteinschneider - Awesome! Glad to hear it worked for you. IMHO, hall sensors are probably the best way to sense a hihat pedal, but there are some nuances you have to get right. In my case, I had to go with a much less powerful magnet to get things working smoothely.
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dsteinschneider
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Re: Hall Effect retrofitted hi-hat stand splash question

Post by dsteinschneider »

What size magnet are you using now? Mine are a pair of magnets from a standard size hard drive
Mr_Bluesguy
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Re: Hall Effect retrofitted hi-hat stand splash question

Post by Mr_Bluesguy »

I went from a 1.2 cm diameter to a .56 cm diameter magnet. They are both very strong neodymium magnets. Not totally sure, but I think that neodymium magnets aren't used in hard drives due to the potential for strong magnetic fields to corrupt data. In retrospect, when I began this project, I didn't need to use such strong magnets, but began with the idea that stronger would be better in terms of sensitivity, etc. Man, was I wrong!
Physical size and field strength aren't necessarily proportional either.
I have a 1.25 cm gap between magnet and sensor at full closure.
It's always a dance between field strength and gap at closure.

You say you are using a pair of magnets. I'm trying to visualize this. Have you just stacked 2 together?
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dsteinschneider
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Re: Hall Effect retrofitted hi-hat stand splash question

Post by dsteinschneider »

@Mr_Bluesguy - yes, they're stacked together and magnetically attached to the rod with InstaMorph moldable plastic wrapped around it.
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