Big Blue Audio Spectrum Analyzer in Dot Mode

The big blue spectrum analyzer with its final software version. The song is from Musical Youth. Last verse was spirit of Jah.

MP3 compression artifacts kill off the high frequency band activity of this analyzer.

If you are fortunate enough to have experienced the sound of a vacuum tube amplifier with CD wav, reel or vinyl input source; then you probably realize what you are missing with MP3 audio.

This device shows high frequency loss of music by MP3.

This 16F877A Microchip PIC powered spectrum analyzer finally works in both dot and bar mode. Response time and accuracy has been optimized over the previous version. All 33 I/O lines of the 40 pin PIC are utilized, many with multi-mode. That is, any of the logic outputs are switched to logic inputs, tri-state and analog inputs on demand. So one I/O pin can become output, digital input and analog input. If software/hardware designed correctly, one logic I/O can be equivalent of 3 or even four I/O. No external switching logic required.

My favorite digital caliper is connected with alligator clip to the touch sensor input to toggle between modes. Any metal object will work.

Category:

Science & Technology

Tags:

• Big
• Blue
• Audio
• Spectrum
• Analyzer
• PIC
• 16F877A
• Microcontroller
• VU
• Meter
• LED
• array
• light
• show

[renek755]

The distortion of a tube amplifier you mean, those things aren't even close to linear.

And no matter how good you can hear. Nobody is going to hear a difference between CD WAV or 320 kbps MP3. There have been enough ABC test done to prove that.

[gavincurtis]

Hi @renek755 320k MP3 I agree with you. But at the time of this video, 8 kHz roll off of lower powered MP3 was common.

Tube amps I prefer the warmer sound and output transformer can indeed color the sound. But so do speakers. The tube sound is warmer to me and cleaner... simply my personal opinion.

[monkeyswithcameras]

are you using the vernier calliper as a switch? or am i just going mad

[loanstar744]

@monkeyswithcameras Yes, a touch sensitive switch I would presume.

[gavincurtis]

@loanstar744 Proximity, it detects capacitance change when the human body is near the closest conductive object. Imagination is the limit. Could be a metal speaker grille, wrench or metal foil hidden behind tinted glass.

[gavincurtis]

@monkeyswithcameras Not insane just yet. The body of the caliper is a proximity detector.

[fgcb1000]

MUITO BOM CARA

[loanstar744]

@gavincurtis Yeah, actually that's pretty much what I meant, a switch that uses the conductivity of an object that comes in contact with it. Just, at the time I was tired, that comment was posted around 3AM.

But in school we called them Touch Sensitive switches which I no doubtably feel dumb for, seeing as that wasn't the actual name for it.

[gavincurtis]

@Putlir I will have new kits about April.

[Putlir]

@gavincurtis

I Can't search your "VU meter kit" on ebay :( Where I Can?

[HouseMusic2oo8]

@zoneco pass the dutchie on the left hand side musical youth