# Re: keyboard and sound

**URL:** <https://psychtoolbox.discourse.group/t/re-keyboard-and-sound/1177>\
**Category:** Uncategorized\
**Created:** [April 20, 2000, 3:34am UTC](https://psychtoolbox.discourse.group/t/re-keyboard-and-sound/1177 "2000-04-20T03:34:25Z")\
**Posts on this page:** 1\
**Page:** 1

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**Author:** ![Allen\_Ingling](https://avatars.discourse-cdn.com/v4/letter/a/a183cd/32.png) [@Allen\_Ingling](https://psychtoolbox.discourse.group/u/Allen_Ingling)\
**Post date:** [April 20, 2000, 3:34am UTC](https://psychtoolbox.discourse.group/t/re-keyboard-and-sound/1177/1 "2000-04-20T03:34:25Z")

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> \>Hi Denis,  
> \>  
> \>I tried to post to the egroup support the other day, but my post never  
> \>showed up, so if I may, I would like to ask you a few questions about PTB:

dear larry  
  
sorry you had trouble. there are no restrictions. if you sent to the   
correct address it should have shown up. Can you confirm that you sent to   
this address?  
  
[psychtoolbox@egroups.com](mailto:psychtoolbox@egroups.com)  
  

> \>1. Is it possible to calibrate the keyboard on a mac G3?

i don't understand. many people want to calibrate a monitor, i've never   
heard of calibrating a keyboard. it is possible to measure time of   
keypress with pretty good accuracy (few ms). The fact that it's a G3 has   
no relevance. Whether the keyboard is attached by ADB or USB may make a   
difference. I'm reasonably sure the software will still work on USB, but   
the word isn't out yet on whether timing is better or worse.  
  

> \>2. With the function SND, is it possible to dynamically vary the loudness  
> \>of system sounds like "Wild Eep" or "Droplet"? (I was able to do it with  
> \>beeps sounds using the sin function and varying the rate)

not directly, but still easily. you'll have to read the snd into an array   
(use READSND), and then play the array in the same way you play your sin   
function. You may need to use ResEdit to copy each of your snds into   
separate files.  
  

> \>2.1. Is it possible to play imported wav (or other) files? and if so, can  
> \>their loudness be varied?

same as above.  
  

> \>3. Do memory intensive functions like SCREEN have any effect on the  
> \>accuracy of recording the speed of key presses?

no, because you can't do both at once. if you alternately monitor the   
keyboard and load a new frame then you won't notice the keypress until   
your software next looks for keypresses.   
  

> \>Thank you,  
> \>Larry James

you're welcome  
  
best  
  
denis