ADAFRUIT AUDIO FX MINI SOUND BOARD - Trigger Question

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zachwire
 
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Re: ADAFRUIT AUDIO FX MINI SOUND BOARD - Trigger Question

Post by zachwire »

ok thanks, i was looking to control the volume with a potentiometer, is there a simple wire example of that on your site? Im guessing vol+ and - to two legs
and ground to the last leg? Will i smoke anything if i just try them all?

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adafruit_support_mike
 
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Re: ADAFRUIT AUDIO FX MINI SOUND BOARD - Trigger Question

Post by adafruit_support_mike »

The + and - pins are digital inputs. Every time you connect one to GND, the volume rises or falls by about 0.5db. Connecting a pot to them wouldn't do anything.

If you want to control the volume with a pot, you'll need to use an external amplifier, with the pot between the FX Board's output and the amp.

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zachwire
 
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Re: ADAFRUIT AUDIO FX MINI SOUND BOARD - Trigger Question

Post by zachwire »

i see, so i can use tactile buttons to go up and down in vol but not a pot without an amp.

I do have an external amp...is there any wiring schematics i could see to show the setup?

Thanks
Z

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adafruit_support_mike
 
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Re: ADAFRUIT AUDIO FX MINI SOUND BOARD - Trigger Question

Post by adafruit_support_mike »

Not specifically.

Connect the pot between the FX Board's L output and GND pins (or R and GND), then connect the external amp to the pot's wiper and GND. The pot will control the amplitude of the signal that goes to the amp.

As a tip, you'll want to use an 'audio taper' or 'log taper' pot. Humans hear ratios of sound pressure more than absolute sound pressure, so 'twice as much sound pressure' sounds like the same increase in volume no matter where it is on the scale.. that's why we measure sound using decibels, which also describe ratios.

For a normal potentiometer, the whole upper half of the sweep falls in the last twice-as-much range, the 1/4-to-1/2 part of the sweep is the next lower twice-as-much range, and so on. Almost all of the audible change in volume will happen down in the first quarter-turn of the knob.

Audio/log taper pots are designed to spread the ratios out so each 1/Nth of a turn produces about the same audible change in volume as any other. We have log-taper pots in the shop:

https://www.adafruit.com/?q=audio%20taper

or you can fake one by connecting a 1.5k resistor between the wiper and GND end of a regular 10k pot. The 1.5k resistor holds the wiper voltage low until about the last 1/6th of the sweep. Any pot and fixed- value resistor with a 6:1 ratio will work the same way.

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zachwire
 
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Re: ADAFRUIT AUDIO FX MINI SOUND BOARD - Trigger Question

Post by zachwire »

whoa! ok...ill work on that


Thanks!
Z

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semegraph
 
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Re: ADAFRUIT AUDIO FX MINI SOUND BOARD - Trigger Question

Post by semegraph »

in case you or anyone lese is having weird issues with the cable not being recognized, I found that I had that issue when I had the reset pin still attached to a non-powered arduino. In my case it was A4, which I used in my code as digital pin 18. Try disconnecting pins that might be attached to a non-powered arduino before you plug in your mini audio fx breakout.

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adafruit_support_mike
 
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Re: ADAFRUIT AUDIO FX MINI SOUND BOARD - Trigger Question

Post by adafruit_support_mike »

Hmm.. interesting point. Thanks for posting to mention it!

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