Random LED visual feedback for Echo Base audio output

[Agung Kurniawan]

Just say that I have 'that' VU meters, how many current did I need to drive 10 LED?

[EBK]

Just say that I have 'that' VU meters, how many current did I need to drive 10 LED?

Probably 110-160mA

[pgorey]

Wow!  That compressor is super cool and I love having visual feedback for compression / expansion to get a visual of the envelope etc.  Very, very slick.  Would love to see the guts as that must have been a tight fit.  Also would love to see a vid if you make one.

[EBK]

Wow!  That compressor is super cool and I love having visual feedback for compression / expansion to get a visual of the envelope etc.  Very, very slick.  Would love to see the guts as that must have been a tight fit.  Also would love to see a vid if you make one.

Some limited gut shots:
http://www.diystompboxes.com/smfforum/index.php?topic=116340.msg1076802#msg1076802

Some details on the compressor itself:
http://www.diystompboxes.com/smfforum/index.php?topic=116252.msg1075858#msg1075858

The microcontroller reads the voltages on the RMS detector output (essentially a measurement of the input level) and the VCA's control pin (a measurement of the amplification/attenuation).  Both are logarithmically scaled already, which makes the dB stuff fairly straightforward.  Through simple addition, the output level is calculated. I'd be happy to tell you anything else you want to know about it.

I've never made/posted a video before.  Perhaps I'll figure that out sometime this week.   

[pgorey]

Wow, you stuffed that one pretty good!  That is some thoughtful and efficient use of space for sure!

[EBK]

Also would love to see a vid if you make one.

This vid is extremely crude.  Low audio so I don't wake the kids, and I can't get the right exposure to see the LEDs very clearly (especially to distinguish red from yellow).  But, maybe it gives you an idea.  In the video, I roughly fumble through the same riff three times and let the final note sustain (1. minimum compression; 2. medium compression (where I usually set it); and 3. max compression).  Again, yellow bar is the output, red means attenuation of the input, and green means amplification of the input.  You'll just have to trust me that there is a single yellow bar at the top of the greens or the bottom of the reds.  At max compression, that yellow bar stays pretty much in the middle as best it can.

I happen to be playing bass in the vid, but this works equally well with guitar.

[Kipper4]

Nice Eric.

[pgorey]

That's pretty cool to see it work.  I can distinguish the different colors.  Would love to hear it with guitar and bass on a recording or video where you can play louder.  Don't worry, I understand the kiddos and trying to keep it quiet and will wait as long as it takes for you to make the vid.  I play most of the time with headphones as we live in a super small apartment so it's either earlier in the day playing or headphones.  Really cool design / logic for the led feedback.

[EBK]

That's pretty cool to see it work.  I can distinguish the different colors.  Would love to hear it with guitar and bass on a recording or video where you can play louder.  Don't worry, I understand the kiddos and trying to keep it quiet and will wait as long as it takes for you to make the vid.  I play most of the time with headphones as we live in a super small apartment so it's either earlier in the day playing or headphones.  Really cool design / logic for the led feedback.

I'm glad you enjoyed seeing that video, despite the technical difficulties making it.  I figured it would be worthwhile to go ahead and post it since it is really a visual demonstration anyway.
As far as the logical design, my main goal was to be able to represent the input and output levels at the same time on a single display in a way that lets the user quickly and intuitively understand which part of the display is which measurement, without slowing the display update down (the software uses a sliding window median filter instead of a linear low pass filter to smooth things a bit).  Im quite pleased with the results. Since you've promised to be patient, I'll eventually figure out to make a much better demo sometime.   

I'll start a new thread next time.  Sorry for hijacking yours.