Author |
Message |
gabbagabi
Joined: Nov 29, 2008 Posts: 651 Location: Berlin by n8
Audio files: 23
|
Posted: Tue May 17, 2016 12:09 pm Post subject:
thru zero VCO Subject description: 4. (SAW) Version added |
|
|
I drew up and soldered this,
but Iam not shure if this is "thru zero ish" enough, because not all (or no) of the zero crossings are looking so nice roundish like i saw it elsewhere
i really like to haer your opinions
cheers bb
gabbagabi
Description: |
|
Filesize: |
93.38 KB |
Viewed: |
1078 Time(s) |
This image has been reduced to fit the page. Click on it to enlarge. |
|
Description: |
|
Filesize: |
59.77 KB |
Viewed: |
837 Time(s) |
This image has been reduced to fit the page. Click on it to enlarge. |
|
Last edited by gabbagabi on Thu Dec 14, 2017 3:39 am; edited 3 times in total |
|
Back to top
|
|
|
vladosh
Joined: Aug 02, 2010 Posts: 659 Location: macedonia
Audio files: 46
|
Posted: Fri May 20, 2016 3:45 am Post subject:
|
|
|
those shapes look interesting for such a small parts count , congrats on the build , could you post some recording from the oscillator , thanks for sharing _________________ http://synthacks.blogspot.com/ шематикс |
|
Back to top
|
|
|
gabbagabi
Joined: Nov 29, 2008 Posts: 651 Location: Berlin by n8
Audio files: 23
|
Posted: Fri May 20, 2016 10:02 am Post subject:
|
|
|
i hope u can hear something interresting out of it
in some i applied a static sinus lfo and sweeped with the cv from -15V to +15V
in some i changed the freq of the sinus lfo and applied a adsr triggered by hand
Description: |
|
Download |
Filename: |
Dist Sin VCO LFO 20HZ Sin.mp3 |
Filesize: |
108.98 KB |
Downloaded: |
1079 Time(s) |
Description: |
|
Download |
Filename: |
dist sin vco sin lfo adsr.mp3 |
Filesize: |
1.55 MB |
Downloaded: |
1079 Time(s) |
Description: |
|
Download |
Filename: |
saw vco variable sin lfo hand adsr.mp3 |
Filesize: |
1.76 MB |
Downloaded: |
1057 Time(s) |
Description: |
|
Download |
Filename: |
SAW VCO sin lfo 111hz plus minus 15V cv sweep.mp3 |
Filesize: |
407.35 KB |
Downloaded: |
1058 Time(s) |
Description: |
|
Download |
Filename: |
SIN VCO sin lfo 111hz plus minus 15V cv sweep.mp3 |
Filesize: |
525.31 KB |
Downloaded: |
1086 Time(s) |
|
|
Back to top
|
|
|
vladosh
Joined: Aug 02, 2010 Posts: 659 Location: macedonia
Audio files: 46
|
Posted: Fri May 20, 2016 12:18 pm Post subject:
|
|
|
modulations sound rich , thanks for the sound samples , cheers _________________ http://synthacks.blogspot.com/ шематикс |
|
Back to top
|
|
|
soundworker
Joined: May 31, 2013 Posts: 21 Location: Germany
Audio files: 1
|
Posted: Fri Jun 17, 2016 1:20 pm Post subject:
|
|
|
TZ VCO can go to 0 herz, oszillation stops. Only TZ VCO can do.
Modulation TZ produces FM-sounds when modulation is going TZ.
In your soundsamles I can´t hear either.
Its seem you are discharching the integration cap depending of sign of modulation CV, but it is not going through zero. It produces a rich color of waveforms. For real TZ you need a cap in the plus and minus part.
klangbauköln |
|
Back to top
|
|
|
Electric Druid
Joined: Mar 13, 2012 Posts: 44 Location: UK
|
Posted: Sat Jul 16, 2016 1:50 pm Post subject:
|
|
|
soundworker wrote: | TZ VCO can go to 0 herz, oszillation stops. Only TZ VCO can do.
Modulation TZ produces FM-sounds when modulation is going TZ.
In your soundsamles I can´t hear either.
Its seem you are discharching the integration cap depending of sign of modulation CV, but it is not going through zero. It produces a rich color of waveforms. For real TZ you need a cap in the plus and minus part.
klangbauköln |
Sorry, but I don't agree. Both the images and the sound samples seem to confirm that's through zero to me. The images clearly show the waveform slowing down towards zero, hitting zero at 0V, and then reversing, as you'd expect.
Similarly, the sound samples sound pretty "FM" to me. Ok, 111Hz isn't a high enough frequency to give you the type of clanging metallic noise you might expect, but it definitely sounds like FM.
It seems like there might be an improvement to be made to try and get the offsets of the two directions identical so that there's no glitch when it crosses over, but given the small number of components, I think it's impressive already.
Tom _________________ Electric Druid Synth and Pedal DIY website |
|
Back to top
|
|
|
Moosgummi
Joined: Feb 01, 2015 Posts: 15 Location: Hiltown, Germany
|
Posted: Tue Aug 30, 2016 6:40 am Post subject:
|
|
|
I don´t really get what´s going on here, but the offset differences are only on the saw wave. I guess it´s a result of the resistor change needed to magically create the saw...
Could a capacitor on the output even this out, or is more magic needed?
Well, I should just build this great simple circuit and try it myself, right?
Edit: Another thing I don´t understand is how the pitch pot works. If I put it to ie 8V, shouldn´t it always stay positive with a +/- 5V input? |
|
Back to top
|
|
|
soundworker
Joined: May 31, 2013 Posts: 21 Location: Germany
Audio files: 1
|
|
Back to top
|
|
|
gabbagabi
Joined: Nov 29, 2008 Posts: 651 Location: Berlin by n8
Audio files: 23
|
Posted: Mon Sep 12, 2016 3:03 am Post subject:
|
|
|
why i got no eMail notification on your posts? Anyway.
I used the Hangover yesterday to going back to this circuit.
First i found a second TZVCO Idea in the folder that ive forgott totally, starting point was the nicolas3141 supersimple saw vco.
Then i played around with offset compensation for the SAW, by using a double switch.
After that i had some fun by simulating the modulation of some points in the circuit.
@soundworker: nice find, and for osamu a, lets say, "easy" design
@moosgummi: you are rigth, i was thinking about that myself to, may the pitch polarity should follow something, but what: the LFO polarity? hm, i guess TCVCOs living of modulations (that are going thru Zero pitchCV ), otherwise they just producing waveform like "normal" vco do. we will see where it goes...
@fyi: the trick with the SAW-Switch is taken from elektor, A. van Ginneken "präziser VCO" (precise VCO), http://sites.prenninger.com/elektronik/elektor/halbleiterheft-inhalt/elektor-1980, it is also in one of there "30x Schaltungen" books
Description: |
|
Filesize: |
166 KB |
Viewed: |
612 Time(s) |
This image has been reduced to fit the page. Click on it to enlarge. |
|
|
|
Back to top
|
|
|
gabbagabi
Joined: Nov 29, 2008 Posts: 651 Location: Berlin by n8
Audio files: 23
|
|
Back to top
|
|
|
L´Andratté
Joined: Sep 23, 2012 Posts: 150 Location: Hamburg, Germany
Audio files: 5
|
Posted: Sat Aug 19, 2017 9:48 am Post subject:
|
|
|
Very nice in it´s simplicity, this is linear cv I suppose? What is the cv voltage range?
Definitly will give this a try as a replacement for the woolaston saw vco in my battery powered synth-to-go! |
|
Back to top
|
|
|
gabbagabi
Joined: Nov 29, 2008 Posts: 651 Location: Berlin by n8
Audio files: 23
|
Posted: Wed Aug 23, 2017 5:10 am Post subject:
|
|
|
Thank you for your interrest.
yes it has linear response. The Input voltage range is only limited by the opamp u use. A good one +/-15V otherwise something like +/-12V.
I see tzvcos more as additional vcos, cos the real vco tasks you can serve better with the classical designs.
keep in mind that u need at least an other vco in front of the tzvco to make sense of the thru zero funktion
a minimal setup in my opinion would contain: classic vco, tzvco, 2xadsr, 2xvca
what iam doing so far is:
pitch adsr - vco- [vca-adsr]- tzvco -
[final vca-adsr]
pitch adsr - vco- [vca-adsr]- tzvco -
and iam more than happy with it, since this i never was thinking that i need a filter (anymore? )
in the next days i will make some sound samples
cheers, gabbagabi |
|
Back to top
|
|
|
gabbagabi
Joined: Nov 29, 2008 Posts: 651 Location: Berlin by n8
Audio files: 23
|
Posted: Sun Aug 27, 2017 4:21 am Post subject:
|
|
|
ok
first: basic tone, sin-out of common vco feed into tzvco. just to visualize the shape of the wave.
Second: saw-out of common vco with ADSR-Pitch feed into a modulated VCA to tzvco- tcvco tri output. Hand crancked modulation sense pot on tzvco.
Third: Adsr is modulating the pitch of the common vco and the VCA , VCA out to TZVCO In. Then i switched from low(635pfF+2,2nF) to high (635pF). Hand crancked modulation sense pot on tzvco.
Fourth: out of common vco feed into modulated VCA then tzvco, i changed the modulationg waveforms from Sine - tri -saw to rec( i handmodulated the pw a little bit)
For me analog FM is kind of "unstable" even more if u work with more then two oscilators and feedback. So my own rule is if u find a nice sound - press instantly record, u will never find it back.
Second thing is u cant play it "tonaly". Just record that sound and than may pitch it in the DAW.
cheers,
gl,
hf
Description: |
|
Filesize: |
72.38 KB |
Viewed: |
401 Time(s) |
This image has been reduced to fit the page. Click on it to enlarge. |
|
Description: |
|
Download |
Filename: |
gabbagabi tzvco basic sinus.mp3 |
Filesize: |
61.35 KB |
Downloaded: |
956 Time(s) |
Description: |
|
Download |
Filename: |
Patch tri out - saw mod.mp3 |
Filesize: |
518.78 KB |
Downloaded: |
982 Time(s) |
Description: |
|
Download |
Filename: |
same adsr patch switch from low to high.mp3 |
Filesize: |
1.26 MB |
Downloaded: |
963 Time(s) |
Description: |
|
Download |
Filename: |
sinusout-mod-by-sin_tri_saw_rec.mp3 |
Filesize: |
457.96 KB |
Downloaded: |
914 Time(s) |
|
|
Back to top
|
|
|
gabbagabi
Joined: Nov 29, 2008 Posts: 651 Location: Berlin by n8
Audio files: 23
|
Posted: Mon Oct 16, 2017 10:35 am Post subject:
|
|
|
new version
edit: startframe of the gif has more information now
Description: |
|
Filesize: |
135.18 KB |
Viewed: |
573 Time(s) |
This image has been reduced to fit the page. Click on it to enlarge. |
|
Description: |
|
Filesize: |
829.79 KB |
Viewed: |
583 Time(s) |
This image has been reduced to fit the page. Click on it to enlarge. |
|
Last edited by gabbagabi on Tue Oct 17, 2017 8:46 am; edited 1 time in total |
|
Back to top
|
|
|
Ricko
Joined: Dec 25, 2007 Posts: 251 Location: Sydney, Australia
Audio files: 27
|
Posted: Tue Oct 17, 2017 8:16 am Post subject:
|
|
|
Lovely to see minimal designs! (Not that there is anything wrong with elaborate designs, if it represents good engineering, of course.)
Rick |
|
Back to top
|
|
|
gabbagabi
Joined: Nov 29, 2008 Posts: 651 Location: Berlin by n8
Audio files: 23
|
Posted: Thu Dec 14, 2017 3:52 am Post subject:
|
|
|
Thx Rick!
Today i add a saw tzvco.
cheers, bb
Description: |
|
Filesize: |
117.51 KB |
Viewed: |
566 Time(s) |
This image has been reduced to fit the page. Click on it to enlarge. |
|
Description: |
|
Filesize: |
904.83 KB |
Viewed: |
428 Time(s) |
This image has been reduced to fit the page. Click on it to enlarge. |
|
|
|
Back to top
|
|
|
Ricko
Joined: Dec 25, 2007 Posts: 251 Location: Sydney, Australia
Audio files: 27
|
Posted: Thu Dec 14, 2017 7:23 pm Post subject:
|
|
|
Nice trick with the comparators!
(Oops I misread them; I thought you had put inverting halfwave rectification, adding this at twice the signal level, so that the negative saw got reflected about 0V. That would be a nice circuit too.) |
|
Back to top
|
|
|
gabbagabi
Joined: Nov 29, 2008 Posts: 651 Location: Berlin by n8
Audio files: 23
|
|
Back to top
|
|
|
gabbagabi
Joined: Nov 29, 2008 Posts: 651 Location: Berlin by n8
Audio files: 23
|
|
Back to top
|
|
|
Grumble
Joined: Nov 23, 2015 Posts: 1294 Location: Netherlands
Audio files: 30
|
Posted: Wed Mar 07, 2018 1:23 am Post subject:
|
|
|
I really like to follow the process of design of this VCO, but the voltages you mention in this diagram are confusing to say the least.. _________________ my synth |
|
Back to top
|
|
|
gabbagabi
Joined: Nov 29, 2008 Posts: 651 Location: Berlin by n8
Audio files: 23
|
Posted: Wed Mar 07, 2018 8:11 am Post subject:
|
|
|
sorry i thought nobody is listening
the green one is the CV
the red one we could call the RAW-SAW
the blue one is the final result after processing it with a trigger which changes polarity when the voltage of the raw-saw (not the frequency) goes thru zero.
a part of that rectangle signal is then mixed thogether with the RAW-SAW to center it around 0V. |
|
Back to top
|
|
|
Grumble
Joined: Nov 23, 2015 Posts: 1294 Location: Netherlands
Audio files: 30
|
Posted: Wed Mar 07, 2018 9:29 am Post subject:
|
|
|
Haha, no I mean the voltages you place at the opamps, like vcc, vdd, 15v and -15v.
Some just seem to float and not connected to anything _________________ my synth |
|
Back to top
|
|
|
gabbagabi
Joined: Nov 29, 2008 Posts: 651 Location: Berlin by n8
Audio files: 23
|
Posted: Wed Mar 07, 2018 10:20 am Post subject:
|
|
|
got it,
thx for the head up.
will be better in comming schemos.
cu |
|
Back to top
|
|
|
elcoco
Joined: Feb 12, 2016 Posts: 8 Location: London
|
Posted: Tue Mar 13, 2018 2:00 am Post subject:
|
|
|
Wow these look great, I'll have to give them a try to hear tem in person. Any idea if running this off 12v would work as well as 15? |
|
Back to top
|
|
|
gabbagabi
Joined: Nov 29, 2008 Posts: 651 Location: Berlin by n8
Audio files: 23
|
Posted: Wed Mar 14, 2018 12:18 pm Post subject:
|
|
|
u need a dual supply
they are designed for +/-15V
it will run from +/-12V
only the amplitude wil not be 5Vpp
a bit less
please let us know how it turned out
at the moment i have no energy in the workshop
so i cant go for further testing these days
the triangle versions are all fully tested
only the first saw version i had on breadboard, like u can see there is a "real-life-scopie"
cheeres, bb
gabbagabi |
|
Back to top
|
|
|
|