Guitar level input?

Hardware questions and issues with the FV-1

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ExertionMusic
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Guitar level input?

Post by ExertionMusic »

Hi all!

If I'm making a PCB that I want to use with guitars, should I put a pre-amp on the PCB?

thanks! having a great time with the chip!
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frank
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Post by frank »

You will need some form of buffer for the guitar signal, guitar signals are rather weak so you will want a buffer with a high input impedance.
Frank Thomson
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ExertionMusic
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Gain?

Post by ExertionMusic »

THank you! Also, would you or other guitar pedal experts recommend any particular gain value? or just a pure unity gain buffer? I've seen elsewhere to have (the relatiely small amount) 3dB of gain, for example. I'm okay with guitarists turning down their volume knob... I don't want to put an extra gain pot on the pedal though.

I see from TFM the maximum analog in values are 2.6V to 3.0V. Can you tell me what the maximum ADC value is?

thanks!
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frank
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Post by frank »

There is no fixed level for guitars, so using a unity gain structure or one that can provide some boost is a good start.

What do you mean by "maximum ADC value"? If you mean the signal then it must never exceed the 3.3V rail but should be set closer to 3.0Vp-p to avoid clipping or distorting.
Frank Thomson
Experimental Noize
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