Music / MP3 / Sound effects

[adamg]

I searched high and low in the forum and archives for an answer to this.. Nobody really asked this question.

What shield / module would you suggest for the following:

1) It doesn't have to only play back MP3 and conversion into any format isn't a problem.

2) I would really like something that makes it possible to speed up and slow down the audio (Not scanning - not playing little bits like a fast forward option - but speed up / slow down) Using a pot to speed up and slow down.

Does anyone know if this would be possible?

Cheers!

 

[Paix]

I believe that you need a chip or system that is more suited to the task of processing digital audio. It would almost certainly require a lot more than integer arithmetic to be able to do a worthwhile job.

Horses for courses and I think that you are looking for something perhaps faster and certainly more general purpose than a Picaxe. Slowing down audio, and in particular music, involves a lot more than just changing the rate.

 

[adamg]

I see. Thanks paix!

I think I might have to forget about changing the speed!

I guess volume is the only thing that you have control over.

Are any of these any good? http://www.mdfly.com/index.php?main_page=index&cPath=9_53&zenid=984893203aeca9a44045c6a407c75eeb

 

[adamg]

I wonder if using this http://mdfly.com/Download/Module/AU5032.pdf

I can change the baud rate - that would have he same effect as slowing down the mp3. I know it would be in big steps - if it worked at all.

What do you think? I wonder if the baud rate can be changed while playing an mp3?

 

[BeanieBots]

The baud rate will only effect the rate at which you can tell the module to do things.
It will have ZERO effect on the speed at which it plays back the music.

 

[adamg]

There goes that idea! Thanks Beaniebots

 

[Jeff Haas]

Adamg, I can tell you that this one, the Tenda TDB380, works well with a Picaxe 08M:
http://www.mdfly.com/index.php?main_page=product_info&cPath=9_53&products_id=284&zenid=984893203aeca9a44045c6a407c75eeb

This module is discussed extensively on this forum, but I can supply some sample code that goes further than what was in the huge thread if you need it, and show pics of my setup.

 

[adamg]

Thanks Jeff!

This is what I would like to do: http://www.adafruit.com/blog/2008/05/21/wave-shield-bending-the-playback-sample-rate/

The format really doesn't matter -in the video above, it uses a wav. Arduino though! >__< I don't suppose that works with a picxe?

 

[Jeff Haas]

Big difference between the Adafruit WAV Shield and the Tenda module. The Tenda module is an MP3 playback board - you give it a command, which is essentially "Play MP3 #1" and it plays it out via a speaker connection on the Tenda board. The microprocessor in this case acts like the CPU in a computer, off-loading the specialized decoding and playback of mp3 music to an audio card.

What the Adafruit shield does is to have the microprocessor play back WAV files (which are uncompressed). This allows the microprocessor to alter the sounds during playback, which is a unique feature of the shield and one that's not usually available on music playback modules. It requires a lot of resources & several pins from the microprocessor to do this. If I were you and I wanted what you see on the Adafruit site, I'd just get the Adafruit shield and an Arduino, rather than taking the time to port everything to another system.

 

[adamg]

Good idea Jeff.

I think I might have to turn to the dark side for this one. I have only just started learning basic though - I hope I can get my hear around the Arduino code! >__< Although I have to say - most of the code I would need has already been written in those tutorials by the looks of it!

 

[Jeff Haas]

Exactly. I have both Arduinos and Picaxes (plus a few Basic Stamps as well!) and I use all of them. I've also created code on one platform and ported it to another for some projects. Learning to do this will make you a better programmer, even if it's for a hobby, like it is with me. The essentials of coding apply in any computer language.

Tip: A lot of the code designed for a Basic Stamp 1 is very easy to port to Picaxe. And there is lots of excellent help already here on these forums, just take the time to work your way through interesting examples and see how they work.