Newbie question about getting trigger pulse out of audio file

[bmachine]

Hello everyone.

I am trying to build a system that will perform the following.  At the touch of a button (or the click of a mouse):

- start playing a 1 minute audio file (to be sent to self powered speakers)
- generate a pulse based on the intensity of this audio in order to trigger a fog machine.  In other words, when the audio is above a certain level, the system will send a pulse to activate a relay and when it dips below that level, it will stop.
- it should also allow me to start a pulse of a predetermed duration (not related to audio).  For example, I want to turn the lights on for 25 seconds.

I hope I am in the right place to ask this question.  I have limited experience in this area so any help or redirection will be much appreciated.  I am on a Mac if that makes a difference.

Thank you very much.

Bo

[JonnyMac]

You could use our AP-8 for sound and a Prop-1 for control, but you'd need to be running an Intel-based Mac with Boot Camp to program it (Parallax programming software for the BS1 only runs in Windows).  If you go this route you can program the fogger control points instead of constructing a "volume detection" circuit for them.

If you're looking for stereo sound (the AP-8 is mono) then we'd suggest you use the Rogue Robotics uMP3 player which is easily interfaced to our prop controllers.

[bmachine]

Thank you John.

Actually I believe there is a Mac version of the BS programming software which I heard about.  it is here:
http://www.muratnkonar.com/otherstuff/macbs2/index.shtml

I am not sure what you mean by "you can program the fogger control points instead of constructing a "volume detection" circuit for them".  What I am looking for is something that will automatically activate the fogger as the audio gets past a certain level.  If you mean to prepgram these points manually it would not be too elegant and would only work with "previously Programmed" audio tracks.  I want to be able to throw any audio at it and have the system activate the trigger based on that.  Does that make any sense?

Thanks very much.

Bo

[JonnyMac]

What you need, then, is a single-channel color organ; you can find these on the Internet to control lights -- often called "lightning simulators."  We don't seem to have the bits you need to solve this problem.

[bsnut]

Hi.

Another way, is to start a FOR-Next loop from the status bits from the AP8(Use the data sheet from the AP8 for more info).

When AP8 starts playing, you get the staus from AP8 saying it is playing, then start the FOR-NEXT loop for the amount of time you need, then you to start the efect.

This should work with no problems.

[Steve_b]

You might look in to VMWare and run an emulated Windows partition.
I've seen it on a windows based machine (we actually loaded Free-DOS for an old application)...works quite well. But not sure about a MAC version.

Something I'm working on (didn't get enough time to work on it before halloween, but the mrs gave me permission for a christmas display....:
I have an Edirol UA-25 USB interface box that lets me plug a guitar/mic in and record to my computer.  Nothing too exciting there....
But it also has MIDI in/out.  Using some old code John did up for some Nutz/Voltz articles, I'm wanna try and set up a track to run regular audio (so outputting to analog outputs/speakers) and on another track, run a Midi organ.
Whenever the F key is pressed on the organ, I'd have a stamp-type device there to decode and then trip the appropriate transistor/relay/switch.

I'm knowledgable enough to work with the stamp, but me thinks a quicker uP is needed to do all I want....but this should work (although requires the purchase of the Edirol type thing-a-ma-jig)!!
Sorry, not based on an EFX-TEK product (I have been watching to see if anyhow had done anything with MIDI on here....)

Cheers

[JonnyMac]

If you buy a Prop-SX I'll show you how to use that as a MIDI-in/digital out device, where each note in theoctave will have a corresponding output from the controller (12 total, P0/OUT0 - P11/OUT11).   You can't do reliable MIDI reception with the Prop-2 because it doesn't buffer serial somes; the Prop-SX can (with the correct code).  You'll also have to make a little interface circuit to go from MIDI to TTL.  In short, what I'll do for you is update the program from this article:

http://www.parallax.com/dl/docs/cols/nv/vol6/col/nv122.pdf

SX/B has matured quite a bit since I wrote that, and I'm a better SX programmer to boot.  But... I don't need such a device so until you have a Prop-SX in your hot little hands I'm going to hold off.   ;D

[Steve_b]

Haha...thanks Jon!

I'm just trying to make the jump from Basic Stamp....I'm on the fence between the SX and the propellor (might there be a propellor based EFX-TEK device in the works)....

I think I've just hijacked this thread....my apologies!

[JonnyMac]

There is no Propeller-based controller in the works -- Spin is way to complicated for casual users.  We might use the Propeller in a design, but it will be "behind the scenes" and the user won't have to program it.