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VFD displays are beloved for their eerie glow that sits somewhere just off what you’d call blue. [mircemk] used one of these displays to create an old-school VU meter that looks straight out of a 1970s laboratory. 

The build uses an Arduino Nano as the brains of the operation, which uses its analog inputs to process incoming audio into decibel levels for display on a VU meter. It’s then charged with driving a GP1287 VFD display. Unlike some VFDs that have preset segments that can be illuminated or switched off, this is a fully graphical dot matrix display that can be driven as desired. Thus, when it’s not acting as a bar graph VU meter, it can also emulate old-school moving-needle meters. Though, it bears noting, the slow updates the Arduino makes to the display means it’s kind of like those dodgy skeumorphic music apps of the 16-bit era; i.e. it’s quite visually jerky.

Overall, it’s a neat project that demonstrates how to work with audio, microcontrollers, and displays all in one. We’ve featured other projects from [mircemk] before, too, almost all of which appear in the same blue and grey project boxes. Video after the break.

A volume unit (VU) meter is a simple gauge that indicates the amplitude of an audio signal, so higher decibels move the needle further. They’re common in the field of audio engineering and music production, with traditional VU meters being analog. But tuning an analog gauge is a challenge, so Mirko Pavleski designed a VU meter that looks analog and comes with all the benefits of a digital device.

Monitoring the amplitude of a signal (like an audio signal) with a microcontroller is very easy — if that microcontroller has an ADC (analog-to-digital converter). MCU processors only understand digital ones and zeros, so the ADC is necessary to translate an infinitely granular analog signal into digital values that approximate it. The Arduino Nano board has eight analog input pins monitored by the ATmega328’s ADC and this project uses two of them: one for the left audio channel and one for the right.

The only other major component for this project is an GP1287 VFD (vacuum fluorescent display), which Pavleski chose for its high contrast and fast response time. It has a resolution of 256×50 and that is wide enough to show two virtual gauges side-by-side. The Nano simply performs an analog read for each audio channel, then updates the graphical gauge using the U8g2 library for monochrome displays. This VFD draws quite a lot of power and that necessitates the use of dedicated power supply. The only other components necessary are resistors, capacitors, and a rotary potentiometer.

The post DIY digital VU meter with analog vibes appeared first on Arduino Blog.

We all love seeing data represented in pretty ways — whether it’s necessary or not. Take VU meters for example. They’re a super useful tool for audio editors to balance signals, but they also look really cool, even if you’re only listening to music. Who didn’t use a Winamp skin with a built-in VU meter back in the day? Even after the demise of everyone’s favorite media player, we still see these great graphs popping up all over the place.

Most recently, we’ve seen VU meters circle back around to have a bit of a retro vibe in this awesome Arduino-controlled LCD VU meter built by [mircemk]. Based on the KTAudio VU Meter project, it features an ultra-wide LCD, audio input, and volume knob, all tidily wrapped up in a case whose color scheme that can only conjure images of the famed Altair 8800, or an old Tektronix oscilloscope. The LCD itself is fairly responsive — but you can judge for yourself in the video below. The signature fading that so commonly accompanies screen refreshes on LCDs such as this one really adds to the retro effect.

You may just need one of these displays on your desk — after all, while you may not need to know how loud each audio channel is, don’t you at least want the information available? Just in case. Bar graph display a bit too modern-looking for you? Well then you should check out [mircemk]’s OLED version that displays dual analog meters.

Ferrofluid is an interesting substance that is attracted to a magnetic field. While manually playing with a flask of such goo is interesting for a few minutes, GreatScott! had other ideas. His 3D-printed rig arranges a half-dozen custom electromagnets on the side of the flask. This allows an Arduino Nano to control the magnetic field arrangement, and thus fluid movement, with the help of six MOSFETs.

To make things a bit more interesting, the build integrates an MSGEQ7 chip to analyze sound frequencies, which enables it to bounce the ferrofluid up and down as a three-zone VU meter. The setup also features a strip of addressable LEDs on the bottom for a lighting effect, creating a neat visual complement to your tunes!

The post A flask of goo that moves to the groove appeared first on Arduino Blog.

Looking for a digital recreation of the classic analog volume unit (VU) meter? If you’ve got an Arduino, a few passive components, and a SSD1306 OLED, then [mircemk] might have the answer for you. As you can see in the video below, his code turns a handful of cheap parts into an attractive and functional audio display.

The project’s Hackaday.IO page explains that the idea is based on the work of [stevenart], with code adapted for the SSD1306 display and some tweaks made to the circuit. While [mircemk] says the code could be modified for stereo as long as the two displays don’t have conflicting I2C addresses, he decided to simply duplicate the whole setup for each channel to keep things simple. With as cheap as some of these parts are nowadays, it’s hard to blame him.

[mircemk] has provided source code for a couple different styles of VU indicators, the colors of which can easily be inverted depending on your tastes. He also clarifies that the jerky motion of the virtual “needle” seen in the video is due to the camera; in real-life it sweeps smoothly like the genuine article.

Much like the project that aimed to recreate authentic “steam gauges” with e-paper displays, this as an excellent technique to file away for use in the future. Compared to authentic analog gauges, these digital recreations are quicker and faster to implement, plus going this route prevents any antique hardware from going on the chopping block.

Plants are great to have around, but they all have different watering needs. If only they could cry out when they’re thirsty, right? Well, now they can. All you need to hear them suffer is your very own Klausner Machine. [RoniBandini] based the Klausner machine on one of Roald Dahl’s short stories, which features an inventor who builds a machine that can make audible the sound of plants shrieking whenever they’re cut.

In [RoniBandini]’s version of the Klausner Machine, the point is to judge the plant’s feelings based on its soil moisture content. An Arduino Nano reads in from the soil moisture sensor, and if the soil is dry, the plant screams. If the soil is moist, the plant emits happy sounds from DF Player Mini and SD card.  We think the analog meters are a great touch, and the jumping needles really anthropomorphize the plant.

Go forth and gain a better appreciation for your plants’ feelings, because this project is wide open. Maybe it will help you water them more often. Some plants need to be cut back, so we think it would be cool if you could make it scream when you take a cutting. Check out the demo after the break.

This is isn’t the first time we’ve seen an analog meter used in conjunction with soil moisture. What is a VU meter, anyway? Our own [Dan Maloney] really moved the needle on the subject a while back.

With his beautifully-colored classroom “noise-o-meter,” Mr. Jones knows when things are getting out of hand.

When you were in school (or if you are in school) the teacher likely told the class to be quiet, perhaps repeating him or herself over an over during the day. The teacher, however, likely never really defined what is good and bad. Mr. Jones has finally solved this issue by creating a classroom “noise-o-meter” using an Arduino, an electret microphone, and a programmable LED strip. In order (apparently) too keep the class in line, noise is simply marked as green for “expected,” amber for “louder,” and “red” for too loud which corresponds nicely with more “traditional” VU meters.

I built this a short while ago as an idea to use in a primary classroom setting. Poster displays are often used by primary teachers wanting to control the noise levels in their classrooms but I wanted to add technology to make it dynamic and responsive. The motivation for this came after seeing the Adafruit Digital NeoPixel LED Strip online and realizing its potential as part of a VU meter.

Are you a teacher and want to build one for yourself? You can check out Mr. Jones’ Instructables page or his own website in a different format.

If you’ve been looking for a simple audio Arduino project, you may want to check out this VU meter from YouTuber RZtronix. The Maker built the device using an Uno along with some LEDs, a couple wires, a breadboard, a sound sensor, and a 5V power supply.

Depending on the music you’re listening to, watching a VU meter bounce to the music is always a good time. So why not integrate the VU meter right into the audio source? That’s what [Matikas] did, and it’s pretty fantastic.

He started with a pair of speakers he had and picked up some NeoPixel LED strips. Carefully wrapping the LED strips around the inside circumference of each speaker, the LEDs fit behind the speaker grills, giving it a cool effect when they’re on.

To control the LEDs, he’s using an Arduino Uno (Atmega328p) which measures the audio level in order to modulate the LED output. A bit of software later (shared on GitHub if you’re interested!) and the VU meters were ready for action — check it out!

As far as VU meters go, we can’t forget this awesome giant-water-tube-VU-display-of-madness.


Filed under: Arduino Hacks, led hacks, musical hacks
Ago
15

3D Printed Bracelet Illuminates On The Beat

3D printing, arduino, bracelet, General, LED, music, VU meter Commenti disabilitati su 3D Printed Bracelet Illuminates On The Beat 

GEMMA on board!Maker Michael Barretta created an LED bracelet that is responsive to sound by combining the technology of light organs and Adafruit’s GEMMA microcontroller. The result is groovy.

Read more on MAKE



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