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I have a friend that wants to hook my drum set's double-bass pedal so that everytime I press it down, it'll light up these kind of LEDs around the 22" diameter bass drum head. Each pedal would be hooked up to approximately half the circumfrence worth of LEDs. His friends in EE suggested that 8 AA batteries for each pedal would be enough, but 16 AAs seems to be a lot. I play drums and kick the pedals at a very fast rate, and we would like to know if plugging them into an outlet (using a 12 VDC power supply) would be safe, given the speed/frequency that the LEDs will be turning on/off. Would it be a fire hazard?

I apologize in advanced if any terminology is off. I myself know little-to-nothing about electrical engineering. (Also feel free to re-tag/re-subject this question - I wasn't sure what to put).

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2 Answers

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... we would like to know if plugging [the LED strips] into an outlet (using a 12 VDC power supply) would be safe, given the speed/frequency that the LEDs will be turning on/off. Would it be a fire hazard?

To answer your question directly and simply: No.

Should you use AA's? No. They will die out very fast, given you could be drawing as much as maybe 1A current with both pedals and multiple LED strips.

The speed at which you turn the LEDs on and off is not a concern. The important thing is you wire everything well, and don't short anything out. Here's a quick list of things you should concern yourself with:

  • The switching system on the bass pedals: Most pedals are almost completely metal, so when wiring things onto it, make sure not to have any bare wires touching the pedal. This is especially important, because somewhere on the pedal you're going to have to make a bare metal contact to act as a switch.
  • The "Current Draw" of your power supply: Look at the "Current Draw" specs of whatever LED strips you choose. Make sure your power supply is rated for well above that, and account for each LED strip you use.

Something trivial to consider: If you play a mean double bass, chances are you may not see much of a "space" between the LEDs going on and off, they will just appear dimmer than if you were to hold the pedal down. This is more-or-less how LEDs like a Macbook's "snoozing" LED gets dimmer and brighter. They (big wave of the hands here, EE's look away) pulse the LED at different rates to change its brightness.

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I'll show my friend this answer and see what thinks. Thanks! I'll get back to you ASAP. – Mike Gates May 31 '12 at 14:09
@MikeGates Any luck with this? – kevlar1818 Jun 6 '12 at 14:21
He likes your answer, and the LEDs should be arriving soon. It may be a week before we install them, but I'm pretty sure he knows what to do now thanks to all of your posts. So thank you everybody! – Mike Gates Jun 7 '12 at 1:33
@MikeGates I'd love to see some footage of the drums if you get them hooked up. Let me know if you post anything to youtube or a blog. – kevlar1818 Jul 23 '12 at 15:20
Sure! Here is some older footage when we first got it working. Since then, my friend fixed it up a bit to be less sensitive to false-kicks. We don't have new footage, sadly. – Mike Gates Jul 23 '12 at 16:58

Very safe if designed and built properly. If you were super caring, running the one foot versions which take 1 Watt each and using a current limitd power supply (ask your EE) would allow you to make the drum units safe against fires if shirted BUT that's really not necessary.

8 x AA is not good enough. If non rechargeable they start at about 12V but drop to 8V over the life of the battery and your LEDs probably go very dim if they run at all.

22" dia drum = 70 inch circumference.
That allows 3 x 20"/50 cm = $30 and some space between strips or eg
2 x 40" = $40? and some overlap or
200" = $100 wound round or cut as required (dear).

You can easily enough make up strip yourself if you want an exact fit, but you swap customisation for convenience. They are charging ~= 40.30/ LED complete so you will not save much doing it yourself.

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What we're going to attach to the bass drum are eight 8" strips of LEDs, 4 for each pedal. So AA's are a bad idea? What would you suggest given that we'll have 32" of LEDs per kick? We intend on using a separate power source for each pedal. – Mike Gates May 31 '12 at 12:27
@MikeGates Where are you seeing the 8 inch strips? I couldn't find them listed on the link you posted. – kevlar1818 May 31 '12 at 13:09
Hmm.. I was assuming my friend was just going to cut them into strips, unless he has another plan.. I'll get back in touch with him, then let you know. – Mike Gates May 31 '12 at 14:06

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