Question regarding "hacking" a guitar tuner.

Thread Starter

errantprogrammer

Joined Jul 10, 2019
4
I have a very basic Korg GA-30 guitar tuner and one of the features is it can play a tone through a small speaker. I thought it would be funny to modify it slightly and include one of those tiny recordable sound modules to also play through the speaker.

So I hooked the power wires into the battery and the speaker wires into the speaker and probably no surprise it does not work like that. I can disconnect the speaker from the tuner and at that point the sound module works but having them both connected gives weird results. The tuner will always work, but the sound module will only play for a second and sometimes it wont work until I play the tuner tones.

I get that it's not supposed to work, but how would I make it work?
 

AnalogKid

Joined Aug 1, 2013
8,138
Sounds like the tuner circuit output impedance is too low for the module to overcome. A DPDT (double-pole, double-throw) switch can connect the speaker to only one device at a time, preventing any conflicts.

ak
 

Audioguru

Joined Dec 20, 2007
11,251
The guitar tuner has an audio power amplifier and the recorder module also has an audio power amplifier. You should Never Ever connect power amplifier outputs together and you are lucky that one or both were not destroyed.
 

Thread Starter

errantprogrammer

Joined Jul 10, 2019
4
The guitar tuner has an audio power amplifier and the recorder module also has an audio power amplifier. You should Never Ever connect power amplifier outputs together and you are lucky that one or both were not destroyed.
Is there any way to make it work? Despite being a complete novice I do have a large assortment of electronic components.
 

Thread Starter

errantprogrammer

Joined Jul 10, 2019
4
Sounds like the tuner circuit output impedance is too low for the module to overcome. A DPDT (double-pole, double-throw) switch can connect the speaker to only one device at a time, preventing any conflicts.

ak
I understand what you are saying, but for academic purposes is there no other way to do this?
 

AnalogKid

Joined Aug 1, 2013
8,138
If you can stand to lose some volume, you can put a resistor in series between each output and the speaker. This will "build out" the output stages so they do not see each other directly.

ak
 
Top