Halloween Forum banner

Off-the-shelf product, flash a light, change its tempo?

1554 Views 13 Replies 6 Participants Last post by  JW Halloween
Is there an off-the-shelf product I can plug a lamp into that will flash it to a predetermined tempo I can set and change?

1 - 14 of 14 Posts
When you say "predetermined tempo", do you mean a steady pattern?
A steady pattern. 125 beats per minute, or 95 bpm, or 133 bpm, etc.
That's one solution, thank you. I'd like to plug a torchiere floor lamp into something that looks like a power strip and have the light pulse at the beat per minute setting chosen. I keep thinking there's something out there already, I just can't think of it.
It's not off the shelf but I could make you a small controller. There would be a pot for adjusting the rate and a solid state relay to turn the light on/off. One thing to consider though is the bulb in your lamp, not all bulbs can handle being flashed at those rates for extended periods.
I need a little help from the electronics whizzes in the forum--my armchair knowledge won't do.

There are plenty of audible tempo tracker Android apps, with nice interfaces, tap pads to determine tempos, and adjustment buttons to increase or decrease tempos by a value of one.

If I get an Andriod app that makes an audible TICKING sound, cut a headphone apart, plug it into the (yes my LG has a) headphone jack, can I run that sound signal into a MOSFET to control a 110AC power strip to flash the light that's plugged in? What's the voltage of the signal going to be, so I can figure out if I need a logic level MOSFET or something else?

It doesn't have to be a filtered signal, it doesn't need to be square wave, etc.
The audio signal needs to be amplified even with a logic level MOSFET. You'd be better off using a KA2284 module to receive the audio signal and tap off of one LED to energize a Solid State 120vac relay.
Seems you should be able to use a DJ light controller like this (https://www.guitarcenter.com/Elation/Light-Saver-2-Channel-Auto-Timer.gc) old school controller for par cans. Or new product coming soon - https://www.guitarcenter.com/Eliminator-Lighting/EC4-4-Channel-Lighting-Controller.gc
Yes. If only it had a digital display of BPM. Oh, so close...

The DJLC is closer for my needs. Thanks for the suggestion, though.
I use these things all the time and it will do what you want it to do.


Its not totally 100 percent plug and play, but a little bit of wiring will get you what you want. It has the ability to have an infinite amount of repeated cycles. For your case, the on cycle would be around .05 seconds followed by a .50 second off cycle.

It would help to understand what you are trying to accomplish. If you are trying to match an audio beat to the light (as a heart beat sound flashing the light as well), I have made that circuit before. I used it back in the day when I dj'ed to get lights to flash to the beat of the bass. It was a line level audio signal going to a voltage regulator, then to an opto-islator, then to a triac (a few other components were involved but the items listed were the nuts and bolts of the circuit). You could use the KA2284 and replace the LED with an opto-isolator then to a triac. Here is a circuit someone else made but its a little involved.

See less See more
My need is this: I coach an a-cappella chorus that needs help keeping tempo. The director tried using a metronome, but failed. IMO, listening to tempo (a sound ticking) while singing (also a sound, duh!) fails because of both singing and metronome being sound modes, they complete and conflict. I want to change the metronome sound into a metronome light.

Watching lights flashing (a visual mode) to indicate tempo matters. I want to try flashing the lights to see if it eliminates what I think is two obstacles (being that both are of a sound mode) butting heads. That's hard to describe.

If I'm reading the list of the board's features, it gets programmed by setting its time-on and time-off durations, then it infinitely repeats an on-off cycle using those time settings.

I wish it had a bpm readout. However, if a song needs to be sung at a 125 bpm tempo, a quick calculation will tell me that 125 / 60 = 0.48 seconds per beat, so, Doug, quit being such a baby. It's totally doable. Program it for a 0.10 on duration, followed by a 0.38 off cycle. Rinse and repeat.

See less See more
Okay, I had something completely else in mind, yea that timer would be a bear to keep changing. Okay, here are a few other ideas.

1. Using a laptop, download a program (Powerpoint may work for this) have a bright color flash on the computer screen for the BPM you need. You could create several different power points each assigned with a specific BPM. You could even connect a separate monitor for a larger screen for the chorus to hear.

2. If you rather have a light, using a laptop with an arduino board, you could create BPM sequences to flash a light through the arduino board.

3. There are several midi devices (aka a keyboard) that you can connect to a DMX controller for relativity cheap.

4. This one is old school. I have connected a 12 volt light to an audio amplifier before. If your metronome has an audio output (or keyboard that can produce a beat) connect it to an audio amplifier and adjust the volume until the light starts flashing. You will need to connect a dummy load (usually resistors) to match the impedance of the amplifier so you don't blow the channel out.

If any of these sound feasible, let me know and I can expand on the details.
See less See more
Here is an app for your phone/tablet that may work. From the description it appears you can make it flash the screen to the beat.

1 - 14 of 14 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.