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
  Rob Adventures in Sound
Please visit the chat
 Forum index » DIY Hardware and Software » Rob Hordijk DIY Designs
Benjolin additions
Post new topic   Reply to topic Moderators: Rob
Page 1 of 1 [8 Posts]
View unread posts
View new posts in the last week
Mark the topic unread :: View previous topic :: View next topic
Author Message
BernhardtSynthesis



Joined: Apr 22, 2010
Posts: 6
Location: Saratoga Springs, NY

PostPosted: Thu Apr 22, 2010 11:29 am    Post subject: Benjolin additions
Subject description: Working with the Binary out of the 4021
Reply with quote  Mark this post and the followings unread

I've been working with this circuit a bit, and I'm wondering (and maybe this should go in the lunetta section, too) what can I do with the 3-bit binary out of the 4021? Are there any worthwhile decoders or processers in the CMOS world that could work with this binary?
Back to top
View user's profile Send private message
textual



Joined: Dec 05, 2009
Posts: 78
Location: New York City
Audio files: 1

PostPosted: Sun Apr 25, 2010 7:15 am    Post subject: Re: Benjolin additions
Subject description: Working with the Binary out of the 4021
Reply with quote  Mark this post and the followings unread

BernhardtSynthesis wrote:
I've been working with this circuit a bit, and I'm wondering (and maybe this should go in the lunetta section, too) what can I do with the 3-bit binary out of the 4021? Are there any worthwhile decoders or processers in the CMOS world that could work with this binary?


Most definitely. I just built this on Saturday at Pete Edwards workshop at Bentfest, perhaps you did too? Pete actually said he created a loop function on board by adding a switch which I believe he said feeds the last stage of the SR back into one of the oscillators? I could be completely wrong there..he said the last bit went somewhere - i.e. its possible.

Either way I was understanding that any of the outs on the Benjolin can be used as either Audio or control and logic could definitely be driven or influenced by it. I plan on moding mine in the next few weeks so that it has all outs patchable as well as an on board mixer. I plan to interface it with my Lunetta as well.

_________________
Dave
______________________
www.dlbelectronics.com
www.textualmusic.com
www.mercuryprogram.com
Back to top
View user's profile Send private message Visit poster's website AIM Address
BernhardtSynthesis



Joined: Apr 22, 2010
Posts: 6
Location: Saratoga Springs, NY

PostPosted: Sun Apr 25, 2010 8:55 am    Post subject: Benjolin Additions Reply with quote  Mark this post and the followings unread

It's funny you'd say that... Pete and I are friends, and we discovered those bends together up here in Troy. You can take any one of the binary outs and reroute it into the Serial input in for sequences from 6 to 8 steps in length. I was more curious if there are any CMOS additions that take, as input, a 3 bit binary and out put anything, or can take in binary and output an interesting result, maybe another feedback loop like the XOR and the 3rd binary out, the "rungler" if you will.
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: Sun Apr 25, 2010 11:15 am    Post subject: Re: Benjolin Additions Reply with quote  Mark this post and the followings unread

BernhardtSynthesis wrote:
You can take any one of the binary outs and reroute it into the Serial input in for sequences from 6 to 8 steps in length. I was more curious if there are any CMOS additions that take, as input, a 3 bit binary and out put anything, or can take in binary and output an interesting result.


You may want to have a look at my post on the 4021 at the Lunetta Designs post of Tue Feb 23, 2010. http://electro-music.com/forum/topic-38634.html&postorder=asc

Just any CMOS gate, shift registers (ehm, any that take inputs and have outputs) can take the 4021 Q6, Q7, Q8 outs, do their thing, and you can reroute the result to the 4021 serial input.

Any potmeter you want modulated, it can be done with the 4051, 4052, 4053 (de)multiplexers. They take 3-bit binary input to route some signal to the output(s). Then you can insert a separate potmeter for each selection.

Ah, the mind boggles with possible schemes. Check the Lunetta forum for some interesting CMOS IC's.

http://electro-music.com/forum/forum-160.html
Back to top
View user's profile Send private message
BernhardtSynthesis



Joined: Apr 22, 2010
Posts: 6
Location: Saratoga Springs, NY

PostPosted: Sun Apr 25, 2010 11:30 pm    Post subject: Benjolin CMOS Reply with quote  Mark this post and the followings unread

Great! That's just about what I was thinking. The Shift registers are a good idea, and I can recreate the type of feedback look Rob has in his design, just further it. Could turn the patterns from epic to epoch.

I'm thinking these chips, along with a 4017 for some more logical (no pun intended) patching could make this thing a beast. I hate to take such a brilliantly simple design and complicate it, but isn't that what tinkering is so often about?

I guess I'll probably hard wire the ABC binary out to the shift registers, just to simplify patching, and also likely hard wire the feedback loop, like the one Rob has made, maybe make it another simple resistor ladder DA converter and feed it back into the serial in on the benjolin or on the auxiliary lunetta set. I love it when a plan comes together.
Back to top
View user's profile Send private message
Rob



Joined: Mar 29, 2004
Posts: 580
Location: The Hague/Netherlands/EC
G2 patch files: 109

PostPosted: Tue May 11, 2010 8:54 am    Post subject: Re: Benjolin additions
Subject description: Working with the Binary out of the 4021
Reply with quote  Mark this post and the followings unread

There is plenty to do with the three bits signal. There are two ways to look at these signals; first as three separate single bit signals, second as a three bit binary code.

Lets say you would want three rhythmic pulses that would drive three percussive sounds on an external clock, e.g. a midi clock. What you would do is use a 4174 six bit latch and route the three Benjolin bits to the inputs of three of the latches. Then you would connect the clock signal to the clock input of the 4174. At the latch outputs of the three used latches you will now find gate signals that flip at the clockpulse. You could also use the pulse output of osc1 as the clock source.

Another idea is to regard the three separate bits as serial bit signals that are pulsed by osc2. Just connect a shift register data input to one of the bits and clock the shift register by osc2. There are several types of CMOS shift registers, some with programmable length up to 64 bits and recirculation possibilities to 'hold' a pattern, others with parallel outputs like the 4006, the 4021 or the 4015 where the parallel outputs can be used to drive e.g. a DA converter or data selector/distributor. With extra shift registers one can extend the length of the time delay of the bits and tap bits from different places, thus enabling canon-type effects.

For a more exact DA-voltage one can connect the three bits to a 4053 analog switch and use it in a three-bit R-2R ladder network, which would turn the 4053 into a three bit multiplying DAC.

By regarding the three bits as a binary code and connecting the three bits to the three select inputs of a 4051 you get an eight input to one output, or one input to eight output switch driven by the Benjolin pattern. One can route audio through the 4051, or control signals. One can also connect eight extra pots to the 4051 and thus create an eight step sequencer for another analog system, where the steps are chosen by the Benjolin but the CV signals that correspond to each step are set by the pots.

Another use of a 4051 is to create a more exact chromatically tuned DA converter that plays a major scale over one octave. To do this the three select bits are connected to the three rungler bits. Then 1% resistors of values of 7k5 and 15k can be used in series between ground and exactly one Volt. The taps on this series are connected to the eight 4051 inputs and the 4051 output is connected to a 1V/Oct input of an analog oscillator. The pulse of osc2 acts as the gate for the analog synth. A series of 15k, 15k, 7k5, 15k, 15k, 15k, and finally 7k5 will give the major scale. Other values or other orders can give other chromatic scales.

Chaining shift registers can give some trouble, as the data inputlevel múst be stable when clocked. To make sure that the chain clocks the data reliably around it is often a good idea to invert the clock. Lets name the pulse from osc2 'C' and the inverted clock 'C-bar'. Now the first shift register chip connected to one of the rungler bits gets clocked by C-bar, the following by C, next one C-bar again, etc. This way the output bit that chains into the next chip will be stable when the next chip is clocked. If one would need a lót of bits from a long chain of shift registers then there is of course now the problem that not all bits flip at the same time. To correct this the bits that come from shift registers that are clocked by C-bar will have to go to inputs of e.g. 4174 latches and the 4174 latches clocked by C. Then the outputs of the latches will flip at the same time as the bits on the shiftregister outputs that are clocked by C.

Delaying the pattern is interesting. E.g., by connecting bit eight of the 4021 in the Benjolin to the data in of another 4021 (while using the inverted clock principle just described) will delay the pattern by eight steps. When a 4051 is connected to the three rungler bits in the Benjolin and a second 4051 is connected to the three output bis of the second 4021 the two 4051s together form an 8x8 matrix where there is always one connection made in the matrix. If one 4051 is used as a 8 to 1 selector and the other as a 1 to 8 distributor and the one in and one out of the 4051s are connected this concoction can e.g. select any one of eight audio signals and send it to any one of eight destinations. But more interesting is when the one in and one out of the 4051s are connected with a diode and the two times eight inputs and outputs are connected to the matrix connections of keyboard of some synthesizer or toy synthesizer (provided it uses an 8x8 matrix to scan its keyboard). As now the Benjolin will play any one of sixtyfour notes on that synth using the rungler circuitry to choose which note to play next. I had good results with driving an old Korg Polysix and a Korg Monopoly this way. But toy synthesizers do often better as they often include their function keys into the keyboard scanning matirx as well, causing the toy keyboard to not only play notes but go to different modes and sounds as well. Uhh, by a toy synthesizer I mean something like the old casio stuff or small key Yamaha stuff, in contrast to e.g. a Sequential Prophet or the like. But many electronic music instruments use matrices to scan their keyboards and function knobs, if the keyboard has five octaves it is almost certain that it uses an 8x8 matrix (=max. 64 keys) and so there is a way to connect a Benjolin to that keyboard (or drumcomputer). And by putting a 6-bit latch like the 4174 between the 4021s and the 4051s and clock the 4174 with an external clock one can synchronize the whole setup to that clock.

These are just some simpler and more advanced examples of what one can do with the bits that come from the rungler circuit in combination with the pulses from the oscs and/or external synchronization pulses. I guess the 8x8 matrix is one of the more interesting options to actually control other circuit-bent stuff. To visualize what this matix does you can imagine that the 8x8 matrix actually drives a field of 8x8 LEDs (another option to build). In this case only one LED will light up at a time and when osc2 pulses the light will go up or down and on the inverted pulse it will go left or right (or vice versa depending on how you orient the led matrix). And as the second three bits are a delayed copy of the original three bits the movement of the light through the field will seem to have a definite correlation.

Aah, so much to say about this. I would advise you to just let your imagination run wild and have fun trying any ideas that pop up...

/Rob

TIP! The CMOS Cookbook by Don Lancaster is in reprint. Though written in the seventies it is still a very valuable source for ideas on what CMOS can do for you and learn about the various CMOS chips and techniques. It is published by Howard W. Sams & Co and has ISBN 0-672-21398-2.
Back to top
View user's profile Send private message Send e-mail Visit poster's website
State Machine
Janitor
Janitor


Joined: Apr 17, 2006
Posts: 2747
Location: New York
Audio files: 24

PostPosted: Wed May 19, 2010 12:31 pm    Post subject: Reply with quote  Mark this post and the followings unread

Quote:
Another use of a 4051 is to create a more exact chromatically tuned DA converter that plays a major scale over one octave. To do this the three select bits are connected to the three rungler bits. Then 1% resistors of values of 7k5 and 15k can be used in series between ground and exactly one Volt. The taps on this series are connected to the eight 4051 inputs and the 4051 output is connected to a 1V/Oct input of an analog oscillator. The pulse of osc2 acts as the gate for the analog synth. A series of 15k, 15k, 7k5, 15k, 15k, 15k, and finally 7k5 will give the major scale. Other values or other orders can give other chromatic scales.


Rob,

Thanks for these fine examples of Benjolin modifications. I like the one above very much !

Bill
Back to top
View user's profile Send private message Send e-mail
inlifeindeath



Joined: Apr 02, 2010
Posts: 315
Location: Albuquerque, NM

PostPosted: Wed May 04, 2011 9:44 am    Post subject: Reply with quote  Mark this post and the followings unread

Hi Rob,
I'm planning on building your DAC 4051 idea, and i want to double check the resistor chain order. the resistors you listed go in series right? so then the 8 outputs would tap in through 7k5 resistors correct? thanks!

_________________
http://www.youtube.com/user/borisandfef
Back to top
View user's profile Send private message Visit poster's website
Display posts from previous:   
Post new topic   Reply to topic Moderators: Rob
Page 1 of 1 [8 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 » Rob Hordijk DIY Designs
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