Waveshield - a question - play speed

[rasterblaster]

Firstly, is it possible to adjust the playback rate of a sample, I saw someone do it with a hard wired variable resistor, however what I want to do is have a soundeffect a 'Pulsing Hum' that changes pace when a input pin is grounded, and then slows back down when its open.

If you give the 'speed' an imaginary number lets say it needs to work like this.

Contact open
'Pulsing Hum' effect plays at constant speed '2'
Contact closes
'Pulsing Hum' effect slowly ramps up to play at constant speed '8' (faster) and keep playing at that rate
Contact opens
'Pulsing Hum' effect slowly ramps down to play at constant speed '2'

also, if it was in the "ramp up" process and had reached speed '6' and the contact opened, it would just go from '6' back down to '2' again...

So basically where ever it is at when a contact opens or closes, it will move from that point either down to '2' or up to '8' depending on the state of the contact...


I hope that makes sense... Its for a sci-fi 'power generator' sound effect, which when activated will ramp up in pitch and speed, but slow back down if a safety switch is activated (ie someone opens it up)
I was going to use different sound effects for up and down, but getting them to sync and play without a gap would be a pain. If I just use the one soundeffect looping continously and adjust the speed, it will 'play fluently'

so the above question is doing it with the software, the other idea is to have ANOTHER arduino control this one (the hard wired variable resistor part).... which might be even easier, and allow more flexibility to tie in with other effects.... thoughts???
I imagine that you can use one to control another (just by hooking up the output pins to the input pins?)

Marty

[adafruit]

the resistor has nothing to do with it, really, its just the sensor. you can do your effect in one arduino without much difficulty.

http://ladyada.net/make/waveshield/library.html

[rasterblaster]

the resistor has nothing to do with it, really, its just the sensor. you can do your effect in one arduino without much difficulty.

http://ladyada.net/make/waveshield/library.html

Well My waveshield turned up today, and I am having a play (thanks for the fast shipping too!)

I have adjusted "wave.dwSamplesPerSec" and it does not seem to change anything.. the pitch or the speed...

is that the one you would adjust to change the pitch on the fly while playing a sample?

[adafruit]

are you changing the variable while the audio plays? it will -reset- the next time its played

[rasterblaster]

As I understand, when the wav is first played, it finds out what the sample rate is from the file, and fills in that variable. (that is what you mean by it resets it I gather)

So the test code I did was to that demo program that finds the samples on the card and plays them one after the other.
it outputs the currently playing name and then "...." as it plays.
I added a line to display the sample rate every time it outputs a "." that works fine.

I then told it to increase the sample rate a bit each time it outpits a "." and display that.
It shows the variable is changing as the sample plays, but the sound does not change. (I have tried various rates of increase, nothing makes a difference) The sample its self goes for about 20seconds... and with an adjustment from 17K to 25K within that time on a 22K file, the sound change should be noticable...

This is the snippit of code - what am I doing wrong?

void playcomplete(char *name) {
playfile(name);
wave.dwSamplesPerSec = wave.dwSamplesPerSec - 5000;
while (wave.isplaying) {
putstring(".");
delay(300);
Serial.print(wave.dwSamplesPerSec);
wave.dwSamplesPerSec = wave.dwSamplesPerSec + 200;
}
card.close_file(f);
}

[rasterblaster]

Ahh I just found a sketch on the net, and I see that it needs to be Set...

wave.setSampleRate(wave.dwSamplesPerSec);
fixes the problem

I aso gotta say that your wave shield frikkin kicks ass.. This has to be the most fun and usefull thing I have purchased off the internet in the last 10 years. SERIOUS!

Its going to give some serious WOW! factor to my sculptures. Thanks so much!

[adafruit]

ugh OK let me fix this