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
<on air> mosc Chez mosc - tonight, Twyndyllyngs live
Please visit the chat
 Forum index » DIY Hardware and Software » Circuit Bending
SK-1 Clock
Post new topic   Reply to topic Moderators: dnny, v-un-v
Page 1 of 1 [5 Posts]
View unread posts
View new posts in the last week
Mark the topic unread :: View previous topic :: View next topic
Author Message
treeclimber



Joined: Aug 09, 2010
Posts: 3
Location: New Zealand

PostPosted: Mon Aug 09, 2010 8:56 pm    Post subject: SK-1 Clock Reply with quote  Mark this post and the followings unread

Hi guys, I'm pretty new to circuit bending, but so far its been awesome fun. After messing around with a kids keyboard, my first project has been my beloved SK-1, and I'm really happy with it, so happy I sold my Alesis Micron.

Though I really enjoy the sounds I'm getting out of the machine at the moment, I'd like to add more layers. I have a few pieces of gear which don't have MIDI, but have digital clocks, so I thought that if I were able to digitally control the tempo of the SK-1 I could just set everything to a particular BPM, start everything at once and all my dreams would come true.

So I'd like to know if its actually possible to stabilize the tempo at all (during bends - right now its temperamental at best) and if so, how I could go about doing it. I'd love to cross bend my Kaossilator with it so it could share a clock signal for example.

By the way, having read through a few old threads, you guys get up to some awesome stuff.
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 Aug 10, 2010 7:43 pm    Post subject: Re: SK-1 Clock Reply with quote  Mark this post and the followings unread

treeclimber wrote:
After messing around with a kids keyboard, my first project has been my beloved SK-1. /.../

If I were able to digitally control the tempo of the SK-1 I could just set everything to a particular BPM, start everything at once and all my dreams would come true.

So I'd like to know if its actually possible to stabilize the tempo at all (during bends - right now its temperamental at best) and if so, how I could go about doing it. I'd love to cross bend my Kaossilator with it so it could share a clock signal for example.


This seems to be not an easy project.

Tempo feel on the SK-1 will remain somewhat temperamental. Especially when using the percussion (drum) channel with bends. However, when pitched way down the envelopes get stretched too, and loose their sense of attack, so Chord and Percussion patterns being off tempo isn't too much of a problem in my opinion.
Running an sk-1 and a Kaossilator from the same clock would probably not get you the results your after.

You could try to give them each their own clock , and run these clocks on the same voltage control. Sam_zen has a schematic for a clock for SK-1 with a 74LS** series IC that has voltage control AND a range offset. It gives you deeper and more stable pitchbend.

For the Kaossilator I recommend the Get-lo-fi clock, it's smaller and can be fit inside the case. With each having their own clock you could drive them on a common voltage. Then you can offset the SK-1 clock to get the tempo/pitch relation you want. (I may insert links here later).

Actually, I think pitching them both separately would give you the best sound. Leaving one pitch unchanged and freaking out on the other's pitchbend leaves some continuity in your music instead of going all over the place.

And you ain't done with bending I suppose. Adding a bent drum machine may get you the synchronized feel. The drum machines signals are synchronous to tempo, and dependant on the sound being played. You can use this as your master bender. Make sure to connect the Grounds from each device together for this to work.

Other idea: Convert several squarewaves from your bent instruments like your drum machine into a voltage ( with a simple to make R/2R DAC , and maybe some CMOS chips to slow the signals down) to pitch your Kaosslilator or SK-1. Check the Lunetta forum for tips and tricks.
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 Aug 10, 2010 7:49 pm    Post subject: Reply with quote  Mark this post and the followings unread

Oops, forgive my impoliteness. Welcome to the forum! Smile

And I love to see / hear demo's of circuitbent stuff (hint, hint).
Back to top
View user's profile Send private message
treeclimber



Joined: Aug 09, 2010
Posts: 3
Location: New Zealand

PostPosted: Wed Aug 11, 2010 4:29 pm    Post subject: Reply with quote  Mark this post and the followings unread

Thanks for the leads Electri-fire. I actually referenced your website quite a lot while I was bulding my SK, it was a great help!

Probably the first question I should have asked was how does the clock on the SK actually work? Does it send a square pulse or a voltage? I did some noodling around yesterday with my Kaossilator, everything is horrifyingly small, and I'm also thinking that syncing/crossbending with a drum machine might be more useful, and, like you say I could use it as a master bender. I think I may get a 555 timer from GetLoFi then see how we go.

I'll probably post some images/sound files later on, though its nothing all that much - more or less just a tablebeast with extra patchbays, part mixing and an external mixing box for signals.
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: Wed Aug 11, 2010 6:38 pm    Post subject: Reply with quote  Mark this post and the followings unread

treeclimber wrote:


Probably the first question I should have asked was how does the clock on the SK actually work? Does it send a square pulse or a voltage?


If I remember right, the internal sk-1 clock is a sinus wave, though inside the CPU this is likely to be squared. It is a high frequency, above 1 MHz at least, maybe 4 MHz even, it's in the service manual somewhere.

Anyway, a 555 timer clock doesn't go fast enough, you need to get this: http://www.getlofi.com/?page_id=1302

to do this to the Kaossilator:
http://www.getlofi.com/?cat=243
http://www.getlofi.com/?p=2709

Maybe also for the SK1:
http://www.getlofi.com/?p=2189

But there I have had good results with Sam_Zen clock. Like I mentioned, you can easilly apply two voltages there, one "main" and one "range adjust".

http://www.xs4all.nl/~samzen/synth/sk1_data.html#hfosc

Sam's handwriting is a horror Laughing , I posted some redrawings here:

http://electro-music.com/forum/topic-43419.html&highlight=


For info on bending drum machines the Burnkit 2600 site is THE place to be.

http://www.burnkit2600.com/
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 1 [5 Posts]
View unread posts
View new posts in the last week
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
emSynth

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