Noisy, buzzy audio problem and massive resistance?! (also, hello, I'm new)

[doctea]

Hello there, I'm new around here and to circuit bending and have been finding it absolutely fascinating poking around over the last few weeks!  Such a rewarding hobby and this seems like a great forum

I'm hoping some kind souls can help me out with a few problems I'm having with my first project...

I've added a line out to a 'dj mixer' toy thing ('mix me dj', I think its the same thing as currently on sale in woolworths as 'smash hits dj mixer') but the output is very buzzy, kind of like a ground hum. 

It was the same on the internal speaker when I first got it so I think its just a dodgy joint somewhere on the board, but can anyone point me to where I should start looking for the solution?  Does it mean I'm on the right track if I can find places where touching/applying pressure to the board makes the buzz worse, and that something around there probably needs resoldering?

When I had the circuit out of the case I'm sure the buzz went away, but now its screwed back in its come back and is highly irritating!

Another question while I'm here - I've also found some basic pitch bends, but the one of these resistors appears to be 230 Mohms - is this at all likely, or is it ludicrously high and I'm misreading the resistor somehow?  Where can I get pots that will let me bend this ultrahigh and ultralow?!

Thanks to any kind souls who can offer some experience and wisdom!

[stolenfat]

some times if i have loose wires not attached to anything they can generate a buzz for my projects, usually solved by unsoldering the wires
also, maybe you need some resistance before your ouput?
just keep trying man and you'll find it
im currently knee deep in a project where i turned a drum machine into a glitch machine controlled by a serial port game controller, very dank

[doctea]

Problem seems to have gone away, at least for now - a combination of using a higher value trimmer pot and powering the speakers off a mains adapter instead of failing batteries seemed to do it!

Cheers for your support :> would be interested in seeing vids/mp3s of your bends..

[doctea]

http://www.doctea.co.uk/misc/mp3/Circuit%20bending/ 

[nochtanseenspecht]

looks good, especially for a first project 
sounds fun, is it a blob chip machine ?

[doctea]

Thanks!
There're two little boards rising up off the main one with a little black blob+resistor on each.  One does the drumpads+keyboard, the other the rhythms+scratch disc.  I didn't dare replace the resistors so there's an 'ultraslow' and 'ultrafast' knob for each, bit wasteful but I'm happy for now

I'll post some internal piccies once I've opened it back up again - I forgot to connect some things back up, and intend to wire in some of the more glitchy bends I found as well as searching for some more

[Circuitbenders]

If you remove the resistor that controls the pitch of the rhythms and scratch sounds you can take the pitch up so high that it crashes and goes all R2D2 on you.

which is nice..........

[doctea]

Well it seems to do that now anyway if i turn the fast pitch knob up too high!  Some weird and wonderful noises indeed.

It also sounds wicked with the rhythms on really really fast speeds, sounds like a fastforwarding tape machine.  You can do some funky tricks with the other pitch knobs which also give it a tape machine feel.

It also has an input for you to connect a CD player up to - I've experimented with feeding the output back into itself via some pots and some of the feedback noises are as good as the noises generated by the machine!  playing noises or rhythms from the machine also modulates and gates the feedback in interesting ways.  the output is very loud though, maybe i just need a massive resistor in line with it too?

There's some internal pics up at the url http://www.doctea.co.uk/misc/mp3/Circuit%20bending/