electro-music.com   Dedicated to experimental electro-acoustic
and electronic music
 
    Front Page  |  Radio
 |  Media  |  Forum  |  Wiki  |  Links
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 
 Forum index » DIY Hardware and Software » Jürgen Haible designs
Trapezoid VCA anybody?
Post new topic   Reply to topic Moderators: fonik, Scott Stites
Page 6 of 7 [161 Posts]
View unread posts
View new posts in the last week
Mark the topic unread :: View previous topic :: View next topic
Goto page: Previous 1, 2, 3, 4, 5, 6, 7 Next

Would you buy a Jh Trapezoid VCA PCB?
no - only interested in the original EMS circuit (this is not goint to happen - sorry)
2%
 2%  [ 1 ]
yes - if it emulates the behaviour of the EMS circuit, and doesn't need component selecting
97%
 97%  [ 40 ]
Total Votes : 41

Author Message
jhaible



Joined: May 25, 2007
Posts: 2014
Location: Germany
Audio files: 24

PostPosted: Fri Nov 26, 2010 12:43 pm    Post subject: Reply with quote  Mark this post and the followings unread

zarko wrote:
Hi Jurgen, i made a new front panel with the attenuator pot,would you tell
me what do you think about Wink


Looks great.

And you could still improove it by making it a reversible attenuator, i. e. zero at 12 o'clock position, and increasing Decay time on cw end (with a positive CV), decreasing decay time on ccw end.

Also, the DC shift potentiometers have no effect in 12 o'clock position. Turning them cw will add a positive DC shift, and turning them ccw will add a nagative DC shift. This refers to both pots: The "+" and "-" means the normal and the inverted output. You can DC-shift them both in both directions.

JH.

_________________
"I tell you the truth, if anyone says to this mountain, 'Go, throw yourself into the sea,' and does not doubt in his heart but believes that what he says will happen, it will be done for him. Therefore I tell you, whatever you ask for in prayer, believe that you have received it, and it will be yours." (Mk 11,23f)
Back to top
View user's profile Send private message Send e-mail Visit poster's website
zarko



Joined: Mar 25, 2010
Posts: 22
Location: France

PostPosted: Fri Nov 26, 2010 2:56 pm    Post subject: Reply with quote  Mark this post and the followings unread

Thanks Jurgen i think now that we have the right final panel.
Let me know if i have to modify other ting Wink


TRAPEZOID VCA V2 copie.jpg
 Description:
 Filesize:  516.4 KB
 Viewed:  875 Time(s)
This image has been reduced to fit the page. Click on it to enlarge.

TRAPEZOID VCA V2  copie.jpg


Back to top
View user's profile Send private message
jhaible



Joined: May 25, 2007
Posts: 2014
Location: Germany
Audio files: 24

PostPosted: Fri Nov 26, 2010 3:51 pm    Post subject: Reply with quote  Mark this post and the followings unread

Looks great! Smile

JH.

_________________
"I tell you the truth, if anyone says to this mountain, 'Go, throw yourself into the sea,' and does not doubt in his heart but believes that what he says will happen, it will be done for him. Therefore I tell you, whatever you ask for in prayer, believe that you have received it, and it will be yours." (Mk 11,23f)
Back to top
View user's profile Send private message Send e-mail Visit poster's website
numbertalk



Joined: May 05, 2008
Posts: 992
Location: Austin, TX
Audio files: 5

PostPosted: Fri Dec 03, 2010 5:52 pm    Post subject: Reply with quote  Mark this post and the followings unread

Not sure if anyone's keeping track or adding fixes to the BOM that got created here anymore, but found 2 more errors - there's a 91K resistor missing and a 3K resistor listed that's supposed to be 2K4.
Back to top
View user's profile Send private message
zarko



Joined: Mar 25, 2010
Posts: 22
Location: France

PostPosted: Mon Dec 06, 2010 10:06 am    Post subject: Reply with quote  Mark this post and the followings unread

Hi
I think that the right value is 3K on the PCB


JH TRAP PCB.jpg
 Description:
 Filesize:  496.03 KB
 Viewed:  813 Time(s)
This image has been reduced to fit the page. Click on it to enlarge.

JH TRAP PCB.jpg


Back to top
View user's profile Send private message
numbertalk



Joined: May 05, 2008
Posts: 992
Location: Austin, TX
Audio files: 5

PostPosted: Mon Dec 06, 2010 10:20 am    Post subject: Reply with quote  Mark this post and the followings unread

zarko wrote:
Hi
I think that the right value is 3K on the PCB


Yeah, I saw that on the web site image too, but my board has 2K4 there, as well as the schematic. JH?
Back to top
View user's profile Send private message
jhaible



Joined: May 25, 2007
Posts: 2014
Location: Germany
Audio files: 24

PostPosted: Mon Dec 06, 2010 1:18 pm    Post subject: Reply with quote  Mark this post and the followings unread

numbertalk wrote:
zarko wrote:
Hi
I think that the right value is 3K on the PCB


Yeah, I saw that on the web site image too, but my board has 2K4 there, as well as the schematic. JH?


2k4 is right.

It was a last minute change. 3k will also work, sort of; but 2k4 will work better in combination with extreme Decay CV settings.

JH.

_________________
"I tell you the truth, if anyone says to this mountain, 'Go, throw yourself into the sea,' and does not doubt in his heart but believes that what he says will happen, it will be done for him. Therefore I tell you, whatever you ask for in prayer, believe that you have received it, and it will be yours." (Mk 11,23f)
Back to top
View user's profile Send private message Send e-mail Visit poster's website
MR-808



Joined: Sep 30, 2010
Posts: 28
Location: Portland, OR

PostPosted: Tue Dec 07, 2010 2:28 am    Post subject: Reply with quote  Mark this post and the followings unread

MR-808 wrote:
janvanvolt wrote:
Anybody got an idea for the frontpanel (5U?)


My partner in synth-building is working on one. I hope to have something worth showing soon!


Too many irons in the fire! We finally put together something we both like. It doesn't conform to the usual MOTM conventions, which will probably tick some people off. Wink My collaborator convinced me that it would be better to put the inputs on the left and the outputs on the right.

I still have a little bit of tweaking to do on the horizontal spacing, but it's very close to what we'll screenprint.


TG.pdf
 Description:

Download
 Filename:  TG.pdf
 Filesize:  64.94 KB
 Downloaded:  850 Time(s)

Back to top
View user's profile Send private message
decaying.sine



Joined: Aug 31, 2009
Posts: 92
Location: New Haven, CT, USA

PostPosted: Tue Dec 07, 2010 5:39 pm    Post subject: Reply with quote  Mark this post and the followings unread

MR-808 wrote:
MR-808 wrote:
janvanvolt wrote:
Anybody got an idea for the frontpanel (5U?)


My partner in synth-building is working on one. I hope to have something worth showing soon!


Too many irons in the fire! We finally put together something we both like. It doesn't conform to the usual MOTM conventions, which will probably tick some people off. Wink My collaborator convinced me that it would be better to put the inputs on the left and the outputs on the right.

I still have a little bit of tweaking to do on the horizontal spacing, but it's very close to what we'll screenprint.


I really like the panel design for your dual trapezoid. Great work!
Back to top
View user's profile Send private message
numbertalk



Joined: May 05, 2008
Posts: 992
Location: Austin, TX
Audio files: 5

PostPosted: Tue Dec 07, 2010 5:50 pm    Post subject: Reply with quote  Mark this post and the followings unread

2 more corrections for the BOM:

There should be 2 470n caps
There should be 2 BC560Cs and 4 BC550Cs (not counting the matched pair that can be replaced by an IC)
Back to top
View user's profile Send private message
wjhall



Joined: Dec 09, 2010
Posts: 1
Location: NJ-USA

PostPosted: Thu Dec 09, 2010 7:47 pm    Post subject: 5U JH Trapeziod VCA panel designs
Subject description: a few design ideas from Bill and Will
Reply with quote  Mark this post and the followings unread

Hi guys -

Will found this thread and thought perhaps we might offer his panel ideas. He did this graphic design, as we usually do, to illustrate the feature set before the panel actually get laid out in FPD or by Scott Deyo or whoever... I think he's got a good handle on the feature set.

This first of his 3 designs includes all of the features represented on Jurgen's schematic diagram. It needs a 3U wide panel. He did another two - one with attenuators for the 3 audio inputs (also 3U wide), and another with just the Trapezoid Generator portion of the features (2U wide).

Please let us know what you think.

Thanks,

Bill and Will


JHTrapezoidVCAV2vIIw1-92in.jpg
 Description:
 Filesize:  65.79 KB
 Viewed:  733 Time(s)
This image has been reduced to fit the page. Click on it to enlarge.

JHTrapezoidVCAV2vIIw1-92in.jpg


Back to top
View user's profile Send private message
bennethos



Joined: Apr 18, 2009
Posts: 31
Location: Belgium

PostPosted: Tue Feb 08, 2011 6:09 am    Post subject:  Sharing is power Reply with quote  Mark this post and the followings unread

I just ordered a PCB as well.
Can't wait to start it !

Thanks again JH for sharing you're brilliant designs to us synth lovers.

Here's an updated and corrected version of the Trapezoid VCA BOM. (I applied the corrections that I've found reading throug this thread).

All the best,
Benjamin


vca_trapezoid_JHaible_BOM.xls
 Description:
Trapezoid VCA BOM 08/02/2011

Download
 Filename:  vca_trapezoid_JHaible_BOM.xls
 Filesize:  11 KB
 Downloaded:  729 Time(s)

Back to top
View user's profile Send private message
jhaible



Joined: May 25, 2007
Posts: 2014
Location: Germany
Audio files: 24

PostPosted: Tue Feb 08, 2011 6:14 am    Post subject: Reply with quote  Mark this post and the followings unread

My Prototype PCB of the trapezoid will be on ebay tonight, starting at 20:00 MEZ.

JH.

_________________
"I tell you the truth, if anyone says to this mountain, 'Go, throw yourself into the sea,' and does not doubt in his heart but believes that what he says will happen, it will be done for him. Therefore I tell you, whatever you ask for in prayer, believe that you have received it, and it will be yours." (Mk 11,23f)
Back to top
View user's profile Send private message Send e-mail Visit poster's website
MR-808



Joined: Sep 30, 2010
Posts: 28
Location: Portland, OR

PostPosted: Tue Jun 28, 2011 1:07 pm    Post subject: Reply with quote  Mark this post and the followings unread

I'm finally getting around to building my JH Trapezoid VCAs, and now that the pcbs are stuffed and missing some parts, I have a few corrections to Bill & Will's BOM (dated 12/9/10). To wit:

Resistors - (3, not 1) 220 Ohm, (5) 470 ohm, (1) 620 Ohm, (1, not 6) 470kOhm.

Capacitors - (9, not 8) 100nF.

Diodes - (11, not 10) 1N4148.

Transistors - (1) 2N5461.

That's it AFAIK. Can't wait to get them wired up and hear how they work!
Back to top
View user's profile Send private message
emdot_ambient



Joined: Nov 22, 2009
Posts: 667
Location: Frederick, MD

PostPosted: Wed Jun 29, 2011 7:47 am    Post subject: Reply with quote  Mark this post and the followings unread

Thanks for the update...I've got 2 of them almost built...not sure where I left off, though. My backlog pile is rapidly becoming my "almost completed PCB" pile. After a while I kind of lost track what's missing from what. Sad
_________________
Looking for a certain ratio since 1978
Back to top
View user's profile Send private message Visit poster's website
MR-808



Joined: Sep 30, 2010
Posts: 28
Location: Portland, OR

PostPosted: Wed Jun 29, 2011 10:32 pm    Post subject: Reply with quote  Mark this post and the followings unread

LOLZ. My "almost completed PCB" pile is growing, too. Wink I've got a "pick-up sheet" where I track what's missing, because I always seem to miss something.
Back to top
View user's profile Send private message
Davedatt



Joined: Jan 12, 2012
Posts: 7
Location: Portland OR.

PostPosted: Thu Jan 12, 2012 10:42 pm    Post subject: Reply with quote  Mark this post and the followings unread

Hey there,

I am debugging the 2nd JH board for our Dual Panel TG. I have reached a point where I am looking for the final bug that is so slight that despite the fact I have it's twin working perfectly now I am at my wits end.

The problem is simple. At maximum off time I still get the unit self cycling about every 7 seconds.

All controls work as its twin.
Maximum cycle times are identical.
No DC offsets on the outputs.

Just wondering if anyone else has seen this. Yes I am and have gone thru the tedious job of checking resister and cap values. I am wondering if I have a tolerance issue with a component.

Sigh....
Dave
Back to top
View user's profile Send private message
Davedatt



Joined: Jan 12, 2012
Posts: 7
Location: Portland OR.

PostPosted: Fri Jan 13, 2012 12:47 pm    Post subject: Reply with quote  Mark this post and the followings unread

Has anyone measured the maximum cycle time or frequency of the trapezoid generator? Or measured stability of the device?

Dave
Back to top
View user's profile Send private message
MR-808



Joined: Sep 30, 2010
Posts: 28
Location: Portland, OR

PostPosted: Wed Jan 18, 2012 5:19 pm    Post subject: Reply with quote  Mark this post and the followings unread

I don't think anybody has actually completed theirs yet. ;)

NOTE: Dave and I have been working on our Trapezoid panels together. I am posting debug comments here in case they help someone else.

In Jürgen's video: http://www.youtube.com/watch?v=KzcAhTQQx3s , he demonstrates the trapezoid being off. So we definitely have a problem.

I also tried to determine the maximum frequency. I couldn't get a good audio signal from the video, so I tuned a synth by ear to match and measured it on the scope. It seems like Jürgen's trapezoid will go up to ~125Hz; ours does about 89Hz. Looking at the images, the attack slope isn't as steep on ours - that could be a clue.

Did using a lower current LED affect the max frequency of yours?

Hmmm...

PS Jürgen, I miss you, and not just because I could use your help debugging this thing. :(
Back to top
View user's profile Send private message
Davedatt



Joined: Jan 12, 2012
Posts: 7
Location: Portland OR.

PostPosted: Wed Jan 18, 2012 7:29 pm    Post subject:   Reply with quote  Mark this post and the followings unread

No, I don't think anyone else has built them. Smile

Looks like we are on our own.


Trap.jpg
 Description:
Proof before the poof!
 Filesize:  157.29 KB
 Viewed:  589 Time(s)
This image has been reduced to fit the page. Click on it to enlarge.

Trap.jpg


Back to top
View user's profile Send private message
emdot_ambient



Joined: Nov 22, 2009
Posts: 667
Location: Frederick, MD

PostPosted: Thu Jan 19, 2012 9:08 am    Post subject: Reply with quote  Mark this post and the followings unread

Pugix, aka Richard Brewster, has completed them:
http://pugix.com/synth/jurgen-haible-trapezoid-vca/

You might want to contact him.

_________________
Looking for a certain ratio since 1978
Back to top
View user's profile Send private message Visit poster's website
MR-808



Joined: Sep 30, 2010
Posts: 28
Location: Portland, OR

PostPosted: Fri Jan 20, 2012 3:32 am    Post subject: Reply with quote  Mark this post and the followings unread

I'm not sure if I fixed it, or if I just applied a band-aid to cover up a build error, but both of mine appear to be working normally. :)

The first clue was when a 'scope probe applied to what I call the "trigger node" (where R19 & R20 meet) caused the occasional trigger to completely go away. At first I thought it might be the capacitance of the probe & cable. Now I'm pretty sure it was the paralleled resistance of the probe dropping the resistance slightly. I replaced R19 with a 1M trimpot and dialed it down to ~950k, and that did the trick! Now it's possible to turn the triggering off completely by turning the OFF TIME all the way down.

I don't think it had any other effect on the circuit - it seems to be able to retrigger just as fast as before the mod.

I'm curious to hear if anybody else has a retriggering problem. Did we make a mistake? Are there parts out of tolerance (resistors are 1%, caps 5%, pots 5%)? Is it just a quirky circuit?

It is odd that Dave had a 4558 and 741 blow. And we both had several bypass caps blow (might just be a bad batch from Jameco - they no longer stock those, I see). I'm going to burn mine in for several hours before I finish assembly. Unless I encounter some other problem, though, I'm going to call it good for now.

Pictures when I'm done testing!
Back to top
View user's profile Send private message
v-un-v
Janitor
Janitor


Joined: May 16, 2005
Posts: 8933
Location: Birmingham, England, UK
Audio files: 11
G2 patch files: 1

PostPosted: Fri Jan 20, 2012 4:03 am    Post subject: Reply with quote  Mark this post and the followings unread

Does anyone know what will come of the PCB for the Trapezoid? I was saving for one, and then we lost Jurgen Sad
_________________
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
emdot_ambient



Joined: Nov 22, 2009
Posts: 667
Location: Frederick, MD

PostPosted: Fri Jan 20, 2012 2:07 pm    Post subject: Reply with quote  Mark this post and the followings unread

I haven't seen anything lately on what's happening with JH's estate. I suspect it will take a while before they figure out what to do with his electronics stuff.
_________________
Looking for a certain ratio since 1978
Back to top
View user's profile Send private message Visit poster's website
Davedatt



Joined: Jan 12, 2012
Posts: 7
Location: Portland OR.

PostPosted: Sun Jan 22, 2012 1:27 am    Post subject:
Subject description: My Build.
Reply with quote  Mark this post and the followings unread

Now works great. Same thing as Mr. 808. 1 meg trim in place of R19, dialed down slightly. I did replace my LED's with 2ma LEDs as well. I suspect our origional or power up failures are related to the original 30ma LED's placing a transiant on the PS busses. Possibly responsible for the bypass cap problems. Little bit concerned about the soft off time, after about 3:00 o'clock I am in a manual time mode. Or at least I got tired of waiting for a re-trigger.

dave
Back to top
View user's profile Send private message
Display posts from previous:   
Post new topic   Reply to topic Moderators: fonik, Scott Stites
Page 6 of 7 [161 Posts]
View unread posts
View new posts in the last week
Goto page: Previous 1, 2, 3, 4, 5, 6, 7 Next
Mark the topic unread :: View previous topic :: View next topic
 Forum index » DIY Hardware and Software » Jürgen Haible 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


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