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Amancue
12-20-2015, 07:57 PM
I'm working on a Voice changer, for a costume
the Goals I have for it are as follows:

Only transmit audio when the button is pressed
Lower the Pitch of the voice being transmitted
add some white noise to the transmission to mimic radio a radio transmission
play a static burst when button is released

I have a Teensy 3.2 and an Audio Shield, I run the output to a powered external speaker. the Input is run to a mic breakout where I can either use normal electect mic or a BlueTooth receiver, that receives the signal from a transmitter that the mic is connected to.
now I have figured out how some of this will happen just learning how to implement said effects, and I'm looking for advice on how to proceed what functions to look into to achieve everything. I have basic electronics knowledge but minimal programming experience. Any help or advice is welcome

if anything else is needed to make what I'm saying clearer please don't hesitate to ask

Donny

stevech
12-20-2015, 11:18 PM
Thought about the problem of feedback - if the mic is in audio range of the speaker?

Amancue
12-20-2015, 11:36 PM
Thought about the problem of feedback - if the mic is in audio range of the speaker?

yes I havnt had too many issues w/ it in my tests so far,..especially after I turned down the gain on the mic input. in the final system the mic will be in the helmet and the speaker will be down in my chest piece so there is distance and some padding and such to baffle those effects

Amancue
12-29-2015, 10:51 PM
So far I've gotten all the basic functions I wanted done for this
When I press the button my speech comes thru, w/ a little bit of filtering and noise to simulate radio
and then when I release the button it plays a radio break sound, and shuts off sound input.

Now I would like to add some voice changing after searching I found a sketch for the teensy that basically does this
from the thread https://forum.pjrc.com/threads/29573-Bat-Detector-96khz-sample-FFT-and-iFFT
now of my couple questions in regard to using this sketch, is there a way to pass the info from the mic input on the audio board to the audio_input_pin or what commands would I use to change it to run from said input. I've seen the talk about the mic breakout from Adafruit. but my issue with it is in the final form my input wont be coming directly from the microphone but instead from a Bluetooth Dongle. A little bit of background on its use, the Microphone will be in my helmet and run over Bluetooth too the Teensy and the Amplified speaker in my chest. my early tests w/ the BT work just fine w/ the receiver plugged into the mic port and my actual mic plugged into a transmitter.

I'm running it PTT for several reasons. the main reason is I dont want it transmitting all the time. I dont want the mic to pick up breathing or my fans all the time.
and then secondly I imagine It'd be less of a drain on the batteries if its only running transforms when the button is pressed.

any help would be appreciated

Donny

PaulStoffregen
12-30-2015, 01:03 AM
is there a way to pass the info from the mic input on the audio board to the audio_input_pin or what commands would I use to change it to run from said input.


The audio board can receive sound from either the mic or the line-level input pins. Use sgtl5000.inputSelect() to choose the signal. Details here (on the right-side panel):

http://www.pjrc.com/teensy/gui/?info=AudioControlSGTL5000

Amancue
12-30-2015, 04:31 PM
I dont think I was clear in what I was asking before, what I meant to ask/say was is there a way to alias or Route Information from the SGTL5000 Mic Input to say pin 16/ADC

PaulStoffregen
12-30-2015, 08:36 PM
is there a way to alias or Route Information from the SGTL5000 Mic Input to say pin 16/ADC

No, that hardware path definitely does not exist. If you look at the audio board schematic, there isn't even any connection to pin 16.

If you read the SGTL5000 datasheet, you'll see there is an all-analog path inside chip from the mic to the headphone amp. The audio library doesn't have code to activate that path, but you could probably adapt the code to enable it. But that will only get the data to the headphone pins. From there, you'd need a hardware mod to get it to pin 16.

Amancue
12-30-2015, 09:44 PM
thank you,.. I'll probably just get a breakout to attach a mic to the analog seems like less work