Archive for November, 2008

Software Vocoding with the Stylophone

Tuesday, November 25th, 2008

So as I said a few weeks ago, I have a Stylophone which is essentially a pocket synthesizer. What I got the idea to to is use the Stylophone as my synth device in post-processing vocoding. I needed to do it post because I don’t (think I) have any equipment that would make me able to vocode audio on the fly. Oh yeah, almost forgot, a vocoder is a device that takes sound (usually a modulated sound like a voice), reduces the amount of information used to store it, and then turns it back into sound by oscillating it according to frequencies in a carrier sound. Basically, you can make mechanical/robotic voices using it.

stypho_lg

So I wanted to make a robot voice using… oh… say… some podcast audio. So first, I trimmed out a little bit of podcast audio in Audacity, my favorite open-source audio editor, which was easy enough. Second, I rigged my Stylophone to my computers audio input and recorded a tone in audacity with vibrato turned on. I wasn’t sure what would be best, so I tried vibrato on, vibrato off, I changed notes while playing, adjusted pitch, etc. I wanted variety. So after I got the tones I wanted, I chopped out the empty space, the mess ups, etc to have a nice flowing audio sample.

So now I had the original audio and my Stylophone audio. How do I vocode? I found a wonderful program a while back called Zerius Vocoder. Now you have to note, its pretty basic and has only a few features, but gets the job done. Also, its free, which is always nice when you’re looking for software to try out.

The Modulator file is my podcast sample, the Carrier file is my Stylophone file, and the Output file is the output. As for the options, I messed around with those until I found what I perceived to be the best combination. There’s always the “Restore Defaults” button if you mess up and want to redo the options.

So after hitting “Vocode”, I have my finished file all ready and waiting to be played. Here are the files I used below…

Modulater File

Carrier File

Output File

After I finished making my new file, I decided to see just exactly how the frequencies changed using another great free tool, Spectro which gives spectrograms of audio waves. So using this, I was able to have visual representations of the frequencies of the audio files. See for yourself,

The modulator file below has an average frequency of 19.5KHz

This podcast audio has an adverage frequency of 19.5KHz

The carrier file below has an average frequency of 22.1KHz

The Carrier file with an adverage frequency of 22.1KHz

The output file below has an average frequency of 22.1KHz

The Output file with an adverage frequency of 22.1KHz

Happy vocoding!

Flea Market Find – Xbox Sign

Sunday, November 9th, 2008

So today, I went to a flea market in New Castle, Delaware and snagged this sign for $10.

xbox

It plugs in, and lights up. Not too sure what I’m gonna do with it, but its pretty cool, and I’d expect hard to find as well.

The Stylophone

Sunday, November 9th, 2008

So about two weeks ago, I ordered a Stylophone from Thinkgeek and have been more than satisfied. For those that don’t know, the Stylophone was a popular toy in the late 1960′s. What sets this toy apart is that it is infact a compact synthesizer. What makes it awesome is the fact that it was used by several big names in music, for example David Bowie played a Stylophone on his song, “Space Oddity” and Kraftwerk used it on their track, “Pocket Calculator”.

stylophone

I purchased a reproduction Stylophone for $20, and certainly got everything I wanted and more. The new Stylophone has three tone settings as opposed to the original Stylophone’s one, so my Stylophone has the same set of tones as the original, but also two additional. I also learned after purchasing that there is a pitch knob underneath the unit, that can be used to tune the Stylophone to the desired key, but can also be used while playing for strange melodic effects. Lastly, there is a vibrato switch on the top next to the power switch, which can make the tones “pulse” in a way that mimics the human voice.

Below is a wav file of some tones I recorded while I was screwing around with it (yeah, this thing has a line out jack).

Stylophone Synth Demo

Hacking around with the N64

Tuesday, November 4th, 2008

So in my summer time, oh so long ago, I picked up with my N64 shenanigans again for the first time in years. Probably about seven years to be more specific. While the software is a lot more advanced then it was back then, we had another innovation called Windows XP which doesn’t really like the software, and a step back, Windows 2K really doesn’t like it. So I had a bit of success on Windows XP with some loopholes, and actually less success then I was supposed to have one one of my surviving Windows 98 boxes. Everything comes down to how the kernel locks down the parallel port of the computer. Windows 98 loves to give away the access, Windows 2K likes to hold onto the access, and Windows XP likes to hold onto it, but let you borrow it if you want to.

So the way it works, through the parallel port of my printer, I hook up a cord that goes to my gameshark, which sits between the N64 console and the game (With the software I have, Goldeneye was used). If you have ever used any console based cheat device, like a Game Genie, you know the kind of in-between cartridge I am talking about.

gstopcgamesharkport1

The Back of the GameShark, showing the SharkPort

So, after I connect everything and set it up, I went to the software side. The first thing I needed was DLPortIO which unlocks the parallel port for the purpose of writing data to devices on connected to the port. It comes with its own basic writing functions, but I only needed it to open access to the port, which it happily did. I then retrieved GE Face Mapper from http://rarewitchproject.com/ which is an excellent website that pushes the limits on games made by the company Rareware years after they come out. I also kept a copy of N64 Utils v3 on hand just in case my Gameshark decided to freak out and delete its own software. It was also useful for retrieving screen caps.

It might not look too nice, but this is one of the outcomes of a texture replacement

It might not look too nice, but this is one of the outcomes of a texture replacement

So I unlocked my ports, and booted up facemapper and started my N64. I turned on the code generator function of the Gameshark to use some of the in-game features, and loaded up Goldeneye, selecting the first level, “Dam”. Once there, I did a ram dump using the GE Face Mapper, which showed me which bitmaps of enemies’ were loaded in the level, and allowed me to replace them with my own bitmaps, overwriting their places in the RAM. After doing that, I was able to dump the screen capture (as you saw above) back onto my computer.


N64 Ram Hacking from Famicoman on Vimeo.

There is plenty more canned software to do texture recreations, but also do things like compeltely redesign levels to load and play on the console. However, my hardware limitations halted these ideas quickly. So unless I can get some stable incarnation of Windows 98 on a nice box, don’t think about it any time soon.