electro-music.com   Dedicated to experimental electro-acoustic
and electronic music
 
    Front Page  |  Articles  |  Radio
 |  Media  |  Forum  |  Wiki  |  Links  |  Store
Forum with support of Syndicator RSS
 FAQFAQ   CalendarCalendar   SearchSearch   MemberlistMemberlist   UsergroupsUsergroups   LinksLinks
 RegisterRegister   ProfileProfile   Log in to check your private messagesLog in to check your private messages   Log inLog in  Chat RoomChat Room 
Live streaming at radio.electro-music.com

  host / artist show at your time
  EdisonRex Edison's Electronic Review
Please visit the chat
 Forum index » DIY Hardware and Software » Circuit Bending
Rapman
Post new topic   Reply to topic Moderators: dnny, v-un-v
Page 1 of 2 [33 Posts]
View unread posts
View new posts in the last week
Mark the topic unread :: View previous topic :: View next topic
Goto page: 1, 2 Next
Author Message
Alexander



Joined: Apr 22, 2006
Posts: 374
Location: 's Hertogenbosch, NL
Audio files: 1
G2 patch files: 4

PostPosted: Mon Mar 29, 2010 5:45 am    Post subject: Rapman Reply with quote  Mark this post and the followings unread

I got myself some casio rapmen! I already experimented and overclocking and glitching it is no problem.. and very very stable!

What i am trying to do right now is create an internal feedback loop, with a pot to control the amount and a switch between external and internal sound source.

Does anybody have any experience with this mod.. please help me out with how to take the output and get it back into the pitch shifter without using cables and a mixer!

Any help is very much appreciated.

_________________
http://husc-sound.com
Back to top
View user's profile Send private message
alienmeatsack



Joined: Mar 04, 2010
Posts: 137
Location: Oklahoma

PostPosted: Mon Mar 29, 2010 2:05 pm    Post subject: Reply with quote  Mark this post and the followings unread

I'm curious too.

It can't be just as simple as connecting the output to the input right? Would you need protection in line as well for accidental backwards current?

_________________
My Circuit Bending Site (Coming Soon)
My Circuit Bending Blog
Back to top
View user's profile Send private message Visit poster's website
electri-fire



Joined: Jul 26, 2006
Posts: 535
Location: breda nl
Audio files: 4
G2 patch files: 4

PostPosted: Mon Mar 29, 2010 4:12 pm    Post subject: Reply with quote  Mark this post and the followings unread

alienmeatsack wrote:
It can't be just as simple as connecting the output to the input right? Would you need protection in line as well for accidental backwards current?


Backwards current? What's that? I think a pot would do. I've seen it done on youtube.

Or a microphone mounted near the speaker.
http://groups.yahoo.com/group/benders/message/13303

I got one waiting to be bent, might have a look someday. Hey,Alexander, if you come to Breda we can have a Rapman Bending Party. Beer etctera 's on me.
Back to top
View user's profile Send private message
alienmeatsack



Joined: Mar 04, 2010
Posts: 137
Location: Oklahoma

PostPosted: Mon Mar 29, 2010 4:34 pm    Post subject: Reply with quote  Mark this post and the followings unread

LOL. I don't know. I've just seen some talk about possibilities of the electricity going backwards. Ignore me. I'm a newb today Very Happy

Is there a trick to bringing the output to the input? Do you just wire the positive to the positive? Do you also wire the ground to the ground?

Is there an easy way to introduce a small delay, maybe a cap? Any precautions like resistors and such that need to be added?

I'm interested in how it works, what tricks to use, etc.

BTW that Yahoo group link does not work for me. Says I have to be a member with no means to sign up.

_________________
My Circuit Bending Site (Coming Soon)
My Circuit Bending Blog
Back to top
View user's profile Send private message Visit poster's website
electri-fire



Joined: Jul 26, 2006
Posts: 535
Location: breda nl
Audio files: 4
G2 patch files: 4

PostPosted: Mon Mar 29, 2010 4:59 pm    Post subject: Reply with quote  Mark this post and the followings unread

Thu Mar 25, 2004 5:11 am "Bryn Truelove" posted on http://groups.yahoo.com/group/benders/

I've been poking around a Casio rapman
and found some bends that I'd like to share. Most of
them effect the beats. Haven't
found anything to effect the pitch. I don't think that it uses an
RC circuit for timing...

All the components on the circuit board are marked with numbers
(R32, C13, ect) so I'll give the number to be connected.

FB1 - R36 = overtone lead overtop of the beat

R16 - FB1 = loud good sound pitch can be changed by 10k pot or
chirping made with 0.02uf cap)

FB1 - emmiter of trans'r by R36 = complex tone lead created over beat

FB5 - a bunch of different places including the tops of electrolitic
capacitors = by far the best of the bunch. When in "rap" mode
with the beat playing quickly make a connection and it produces
random well timed glitched out loops or crashes out compleatly. Use
on/off sw. to reset.

FB4 - R12/R13/R14 (and a bunch of other places) = pretty much the
same as above but seems to make different sounding loops. Good to
do the above glitch first and then this one after to change it a bit.

Also there are two area's on the left and side of the board with
five or six parallel jumpers (wires). One group running up and down
and the other running side to side. I can't figure out how to
explain which wire is which, but... with a beat playing, poke around
in there, connecting one group to the other, until something good
happens. You should get an overtone that plays along with the
beat. This is also one of my fav's.

Last thing and maybe the best, /.../. The rapman has a builtin "voice effector" which
pitchshits your voice up or down (in octaves or fifths I think). I
bought one of the $2 mikes that they sell in dollar stores around
here and took out the small plastic cylinder that the diaphram is
mounted in and then hooked it up perminantly to the keyboard. The
first cool thing that you can do with this is hum into it like a
kazoo and it makes a wicked, very electronic sounding lead. Doesn't
sound anything like anything make by a mike. The second thing that
you can do with this little mike is hold it infront of the speaker
for some nasty sounds. It picks up whats playing and pitch shifts
it up or down. You can also control the feedback to the point that
you can actually play it. Put the mike close for three counts take
it away for one. /.../

(Disclaimer: shortened by electri-fire. If anyone objects to my copying/editting this post it will be deleted.)
Back to top
View user's profile Send private message
electri-fire



Joined: Jul 26, 2006
Posts: 535
Location: breda nl
Audio files: 4
G2 patch files: 4

PostPosted: Mon Mar 29, 2010 5:15 pm    Post subject: Reply with quote  Mark this post and the followings unread

alienmeatsack wrote:
Is there a trick to bringing the output to the input? Do you just wire the positive to the positive? Do you also wire the ground to the ground?

Is there an easy way to introduce a small delay, maybe a cap? Any precautions like resistors and such that need to be added?


Start with inserting a potentiometer between the (positive) in and output.

Suppose you wire it so turning clockwise reduces resistance, so you get more feedback (middle and right solderlug when looking from top side).

When feedback gets too much to your taste, set the pot to the amount of feedback you want at maximum, and measure the resistance between the middle and right lug.
Now insert a resistor of that value (or slightly higher) in series with the pot. This resistor can be inserted anywhere in the feedbackpath, at the circuitboard, at the pot, whatever.

There's no need to do something with the ground connection when feedbacking within one device.

Capacitors can be used, but work as a filter, not delay in the usual sense.
Back to top
View user's profile Send private message
Sam_Zen



Joined: Mar 08, 2008
Posts: 251
Location: NL

PostPosted: Mon Mar 29, 2010 7:01 pm    Post subject: Reply with quote  Mark this post and the followings unread

Some additions about feedback :

out - in :
It's always asking for trouble to directly wire some output of a device straight into its own input.
Always start with some component in between, pot or resistor.
Sometimes a feedback situation ends up very quickly in a very high frequency oscillation,
which can cause serious power consumption problems, like a CPU running at 100 %, so much current.
These HF signals can be often sufficiently dampened even only by the presence of a resistor,
which has also a capacitance on its own, so acts as a tiny filter too.

Ground :
If the connection is an internal one of the device, there's no need to connect the V- of the output plug to the V- of the input plug.
On the contrary, it could mean a "groundloop" in the system, causing a net-hum (50/60 Hz) on the line.
A caution : Not all outputs, like a headphone plug, have as 'minus' the common power ground V-.
Sometimes it has a "floating zero", which is not the same.

_________________
0.618033988
Back to top
View user's profile Send private message Visit poster's website
Sam_Zen



Joined: Mar 08, 2008
Posts: 251
Location: NL

PostPosted: Mon Mar 29, 2010 8:08 pm    Post subject: Reply with quote  Mark this post and the followings unread

I was curious about this Rapman, did a search and came upon :
http://www.synthmania.com/rapman.htm
Quite a lot of demo MP3 samples.They are mono, no problem.
But concerning timing, these samples are just sloppy crap.
Just choose a beat from the pattern section, having your player set in 'repeat' mode, knock the beat on the table,
and you'll see what I mean.

Is there some technical circuit available of the Rapman by the way?

_________________
0.618033988
Back to top
View user's profile Send private message Visit poster's website
Alexander



Joined: Apr 22, 2006
Posts: 374
Location: 's Hertogenbosch, NL
Audio files: 1
G2 patch files: 4

PostPosted: Tue Mar 30, 2010 12:20 am    Post subject: Reply with quote  Mark this post and the followings unread

Great info! This helps. I searched for a technical schematic or service manual, but I still haven't found what I am looking for!

I'll open one up completely and take some pictures of the circuitboard, makes it easier to locate the bends!

Another thing I am trying, is replacing the pitchswitch with a pot, to have more options for shifting! Default is 1 or 2 oct down and up!

Great help, you guys rock as always!

@electri-fire I am in Breda soon for my sis' curfew evening, it's the 15th! Maybe we could meet and plan this beerbendfest! Very Happy

_________________
http://husc-sound.com
Back to top
View user's profile Send private message
Alexander



Joined: Apr 22, 2006
Posts: 374
Location: 's Hertogenbosch, NL
Audio files: 1
G2 patch files: 4

PostPosted: Thu Apr 01, 2010 7:37 am    Post subject: Reply with quote  Mark this post and the followings unread

I found this attached datasheet, this could be very useful in doing a lot of weird things with the voice changer!


556921_1.pdf
 Description:
datasheet for OKI M6322 voicechanger ic

Download
 Filename:  556921_1.pdf
 Filesize:  545.17 KB
 Downloaded:  268 Time(s)


_________________
http://husc-sound.com
Back to top
View user's profile Send private message
alienmeatsack



Joined: Mar 04, 2010
Posts: 137
Location: Oklahoma

PostPosted: Thu Apr 01, 2010 9:26 am    Post subject: Reply with quote  Mark this post and the followings unread

I keep trying to find one of these... But am taking notes here when I do iuntil then!
_________________
My Circuit Bending Site (Coming Soon)
My Circuit Bending Blog
Back to top
View user's profile Send private message Visit poster's website
Alexander



Joined: Apr 22, 2006
Posts: 374
Location: 's Hertogenbosch, NL
Audio files: 1
G2 patch files: 4

PostPosted: Thu Apr 01, 2010 1:01 pm    Post subject: Reply with quote  Mark this post and the followings unread

I'm photographing the process, it wiill make a nice blog entry when I get done.. For now I'm going for a simple glitch crossfader option, internal feedback and magenta spraypaint!! I've got a few spare ones, to experiment further with!

Maybe i could control the pitch shifter by the pwm signal from my arduino! That would make my first casio with usb.. Wink

_________________
http://husc-sound.com
Back to top
View user's profile Send private message
alienmeatsack



Joined: Mar 04, 2010
Posts: 137
Location: Oklahoma

PostPosted: Thu Apr 01, 2010 1:08 pm    Post subject: Reply with quote  Mark this post and the followings unread

Do it! Sounds liek a fun bend too!
_________________
My Circuit Bending Site (Coming Soon)
My Circuit Bending Blog
Back to top
View user's profile Send private message Visit poster's website
telstarmagikistferrari



Joined: Jun 16, 2008
Posts: 276
Location: Indianapolis, Indiana
Audio files: 43

PostPosted: Thu Apr 01, 2010 11:40 pm    Post subject: Reply with quote  Mark this post and the followings unread

man those beats that dude sampled are R-R-R-RAW! also hilarious. His tickling of the ivory just pisses me off, but at least he left a bar or two on most of them before he comes in. Cool thread, can't wait to hear the bends.
Back to top
View user's profile Send private message Visit poster's website Yahoo Messenger
Alexander



Joined: Apr 22, 2006
Posts: 374
Location: 's Hertogenbosch, NL
Audio files: 1
G2 patch files: 4

PostPosted: Fri Apr 02, 2010 12:59 am    Post subject: Reply with quote  Mark this post and the followings unread

NOTE:

- The numbering of components mentioned above by elctri-fire, is only on realistic versions, the casio has the values of the components, not the numbers!

_________________
http://husc-sound.com
Back to top
View user's profile Send private message
Alexander



Joined: Apr 22, 2006
Posts: 374
Location: 's Hertogenbosch, NL
Audio files: 1
G2 patch files: 4

PostPosted: Sat Apr 03, 2010 6:19 am    Post subject: Reply with quote  Mark this post and the followings unread

Well I'm done! Smile

I finished one with a distortion button, feedback pot and glitch pot (both with on/off switches). To make it more usable I added a 1/4 line output and a speaker mute switch..

.. now it's time to enjoy the rest of this long weekend.

I will record and upload some samples and further discuss this. I now have a much better idea of what is possible and I made all the mistakes to learn from!


BILD1106.JPG
 Description:
circuit bent casio rapman
 Filesize:  234.47 KB
 Viewed:  192 Time(s)
This image has been reduced to fit the page. Click on it to enlarge.

BILD1106.JPG



_________________
http://husc-sound.com
Back to top
View user's profile Send private message
alienmeatsack



Joined: Mar 04, 2010
Posts: 137
Location: Oklahoma

PostPosted: Sat Apr 03, 2010 6:31 am    Post subject: Reply with quote  Mark this post and the followings unread

Yea! Good job dood, now where are the pics and sound samples and the discussion? Very Happy
_________________
My Circuit Bending Site (Coming Soon)
My Circuit Bending Blog
Back to top
View user's profile Send private message Visit poster's website
Alexander



Joined: Apr 22, 2006
Posts: 374
Location: 's Hertogenbosch, NL
Audio files: 1
G2 patch files: 4

PostPosted: Sat Apr 03, 2010 6:52 am    Post subject: Reply with quote  Mark this post and the followings unread

".. now it's time to enjoy the rest of this long weekend. "

Very Happy

EDIT: it's bad to post pictures ( more pictures are on my blog ) and no sound in a circuit bending forum Wink , here's a quick and dirty demo:

http://husc-sound.com/stuff/rapmasta_dirty_demo.mp3

_________________
http://husc-sound.com
Back to top
View user's profile Send private message
Alexander



Joined: Apr 22, 2006
Posts: 374
Location: 's Hertogenbosch, NL
Audio files: 1
G2 patch files: 4

PostPosted: Tue Apr 06, 2010 1:46 am    Post subject: Reply with quote  Mark this post and the followings unread

Nobody...?
_________________
http://husc-sound.com
Back to top
View user's profile Send private message
electri-fire



Joined: Jul 26, 2006
Posts: 535
Location: breda nl
Audio files: 4
G2 patch files: 4

PostPosted: Tue Apr 06, 2010 5:19 am    Post subject: Reply with quote  Mark this post and the followings unread

[quote="Alexander] it's bad to post pictures and no sound in a circuit bending forum Wink[/quote]

Well, it's got a beauty paint job. Smile

[quote="Alexander]here's a quick and dirty demo:[/quote]

Nice! And thanks for posting the pitch changer datasheet. Very interesting. For a moment I even considered to remove the chip from the Rapman and put it in a seperate little box.
Back to top
View user's profile Send private message
Alexander



Joined: Apr 22, 2006
Posts: 374
Location: 's Hertogenbosch, NL
Audio files: 1
G2 patch files: 4

PostPosted: Tue Apr 06, 2010 10:51 am    Post subject: Reply with quote  Mark this post and the followings unread

Nice, thank you!! Very Happy

I have been thinking about taking the ic out and doing something with the twelve stages of pitch shifting, but the ic doesn't have long legs and is (i think) impossible to remove, without damaging it..

It did give me new ideas for g2 patches! Smile

This one was a lot of fun, I found my old Boss DS2 still works, so that one is next, but I'll try and follow up with more experiments with the pitch shifter!!

_________________
http://husc-sound.com
Back to top
View user's profile Send private message
Sam_Zen



Joined: Mar 08, 2008
Posts: 251
Location: NL

PostPosted: Thu Apr 08, 2010 8:51 pm    Post subject: Reply with quote  Mark this post and the followings unread

nice demo !
_________________
0.618033988
Back to top
View user's profile Send private message Visit poster's website
v-un-v
Janitor
Janitor


Joined: May 16, 2005
Posts: 8932
Location: Birmingham, England, UK
Audio files: 11
G2 patch files: 1

PostPosted: Fri Apr 09, 2010 12:35 pm    Post subject: Reply with quote  Mark this post and the followings unread

Alexander wrote:
Nobody...?


Laughing

Fab mp3 demo! Cool

I don't know what happened to my Rapman Sad Perhaps I put it on eBay, and now I can't remember? Shocked

_________________
ACHTUNG!
ALLES TURISTEN UND NONTEKNISCHEN LOOKENPEEPERS!
DAS KOMPUTERMASCHINE IST NICHT FÜR DER GEFINGERPOKEN UND MITTENGRABEN! ODERWISE IST EASY TO SCHNAPPEN DER SPRINGENWERK, BLOWENFUSEN UND POPPENCORKEN MIT SPITZENSPARKSEN.
IST NICHT FÜR GEWERKEN BEI DUMMKOPFEN. DER RUBBERNECKEN SIGHTSEEREN KEEPEN DAS COTTONPICKEN HÄNDER IN DAS POCKETS MUSS.
ZO RELAXEN UND WATSCHEN DER BLINKENLICHTEN.
Back to top
View user's profile Send private message Send e-mail
Alexander



Joined: Apr 22, 2006
Posts: 374
Location: 's Hertogenbosch, NL
Audio files: 1
G2 patch files: 4

PostPosted: Sat Apr 10, 2010 3:10 am    Post subject: Reply with quote  Mark this post and the followings unread

Quote:
Perhaps I put it on eBay, and now I can't remember?


Maybe it ended up on the desk of a young dutch audiogeek? Very Happy

_________________
http://husc-sound.com
Back to top
View user's profile Send private message
spam4life



Joined: Jan 16, 2008
Posts: 21
Location: argentina

PostPosted: Sat Apr 24, 2010 3:18 am    Post subject: Reply with quote  Mark this post and the followings unread

great!!!!
can you do a "how-to" of the feedback mod?
Back to top
View user's profile Send private message
Display posts from previous:   
Post new topic   Reply to topic Moderators: dnny, v-un-v
Page 1 of 2 [33 Posts]
View unread posts
View new posts in the last week
Goto page: 1, 2 Next
Mark the topic unread :: View previous topic :: View next topic
 Forum index » DIY Hardware and Software » Circuit Bending
Jump to:  

You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum
You cannot attach files in this forum
You can download files in this forum
e-m mkii

Please support our site. If you click through and buy from
our affiliate partners, we earn a small commission.


Forum with support of Syndicator RSS
Powered by phpBB © 2001, 2005 phpBB Group
Copyright © 2003 through 2009 by electro-music.com - Conditions Of Use