so has anyone built that fancy BERGFOTRON VCO?

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Norman_Phay

so has anyone built that fancy BERGFOTRON VCO?

Post by Norman_Phay » Thu Jun 30, 2011 11:42 am

This, specifically, I mean:

http://hem.bredband.net/bersyn/VCO/vco_advanced.htm

It looks interesting ("Interesting" is an understatement, maybe) It also looks...challenging ("challenging" may also be an understatement I fear).

It offers:
Buchla VCO core
Octave quantizer
Advanced VCO waveshaper
Woodwind waveshaper (? espcially intrigued by this)
VC divide by N
Two channel, eight position VC waveform selector

I note that there are full docos on the page, including PCB overlays by the look of it. I cannot find anywhere on the guy's site where he offers PCBs for sale. Has anyone contaced him w/r/2 making a run or two, maybe? Maybe also for some of his other circuits. Or, does he actually offer PCBs and I am too DUMM to find the page :D

List of DIY modules & standards here:

http://hem.bredband.net/bersyn/amore.htm

Supply voltage standards look a bit unusual?

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Hi5
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Post by Hi5 » Thu Jun 30, 2011 11:48 am

I have lusted over such a vco but it is a challenge beyond my abilities now.
Beautiful design though.

Norman_Phay

Post by Norman_Phay » Thu Jun 30, 2011 12:04 pm

There is an earlier take as well, the "complex VCO":

http://hem.bredband.net/bersyn/VCO/vco_complex.htm

I saw this years ago - I don't like to think how many - wanted to make one so bad, but it was way, way beyond my capabilities. 3 PCBs! It still looks awesome.

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mono-poly
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Post by mono-poly » Thu Jun 30, 2011 12:11 pm

I am really intriged by the woodwindwaveshaper.
Love to see it as a standalone pcb.
The farad is the captain of my print.

http://www.mono-poly.nl
http://www.noodlebar.org

WTB blue lantern purple vco

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J3RK
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Post by J3RK » Thu Jun 30, 2011 1:17 pm

I'm quite interested in just the triangle core. Another wiggler and I have been trying to get proper simulations of it before building, but the outputs always behave very strangely. It may just be a limitation in the sim though, so building one may work better. I plan to do it when I have time. Seems like a good core to build on. I haven't taken a look at his site in a while, but I wonder how well it tracks. If I remember correctly, it's a PNP based expo-converter, (like the 258ish clone uses,) so may not be the most amazing V/Oct tracking in the world. (the 258ish gets around 3+) I think he uses a MAT though, so that may help a little.


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JRock
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Post by JRock » Fri Jul 01, 2011 12:03 am

I got the impression that he etched all that stuff himself :hmm:
Been a little while since I checked it out. Way too much to handle when I first started. Have to revisit .

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Luka
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Post by Luka » Fri Jul 01, 2011 1:00 am

i have been tempted on ocassion but never took the plunge - i agree with dennis about interest in a standalone woodwind shaper

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Peake
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Post by Peake » Fri Jul 01, 2011 12:49 pm

Gotta build other things first. :hihi:
This is not the place I'd imagined it to be.

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Bergfotron
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Post by Bergfotron » Mon Aug 29, 2011 3:10 pm

If I do a simpler VCO with the Woodwind Waveshaper, what VCO core do you prefer?
The Buchla triangle core that the Bergfotron Advanced and Complex VCOs use does have it's limitations. It's a quite decent core but triangle cores have some inherent drawbacks. It doesn't have to be a triangle core but I do think that the Woodwind Waveshaper should be accompanied with it's own VCO core.
So is there a consensus as to which is the best VCO core that still isn't too complicated and doesn't use too exotic parts?

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Hi5
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Post by Hi5 » Mon Aug 29, 2011 3:33 pm

triangle or saw is fine by me. anything to get all the shapers in your design.

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Dego
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Post by Dego » Mon Aug 29, 2011 4:23 pm

Hi5 wrote:triangle or saw is fine by me. anything to get all the shapers in your design.
+1

Less exotic parts sounds good.

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Post by emdot_ambient » Mon Aug 29, 2011 9:19 pm

+1 I have no clue what advantages either would have, so either will do :mrgreen:

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Neutron7
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Post by Neutron7 » Mon Aug 29, 2011 10:27 pm

the circuit for the woodwind waveshaper should be dooable quite easy, people with modulars can probably do it without buying anything,

one idea is sync a pulse VCO with a narrow pulse width(narrower than the time of your highest note) that is at a fixed frequency lower than your lowest note, and is synced to the tuned one. you will get a fixed width pulse and "woodwind waveshaper" sound, sync 2 and invert one of them, for more fun!

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PF
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Post by PF » Tue Aug 30, 2011 12:50 am

Bergfotron wrote:If I do a simpler VCO with the Woodwind Waveshaper, what VCO core do you prefer?
The Buchla triangle core that the Bergfotron Advanced and Complex VCOs use does have it's limitations. It's a quite decent core but triangle cores have some inherent drawbacks. It doesn't have to be a triangle core but I do think that the Woodwind Waveshaper should be accompanied with it's own VCO core.
So is there a consensus as to which is the best VCO core that still isn't too complicated and doesn't use too exotic parts?
:hail: :hail:

As mentioned already saw and tri..

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3vcos
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Post by 3vcos » Tue Aug 30, 2011 1:07 am

Bergfotron wrote:If I do a simpler VCO with the Woodwind Waveshaper, what VCO core do you prefer?
The Buchla triangle core that the Bergfotron Advanced and Complex VCOs use does have it's limitations. It's a quite decent core but triangle cores have some inherent drawbacks. It doesn't have to be a triangle core but I do think that the Woodwind Waveshaper should be accompanied with it's own VCO core.
So is there a consensus as to which is the best VCO core that still isn't too complicated and doesn't use too exotic parts?
People on various forums (including this one) are making a big deal about triangle core vcos these days. They do sound nice when used with buchla type waveshaping. That said buchla never comes to mind when I think of woodwind type sounds.

I'd rather hear what suggestions you have for vco cores that would compliment the sound of your woodwind waveshaper.

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Post by ultrashock » Tue Aug 30, 2011 4:22 am

Triangle core is good at Buchla stuff (famous expo. fm, phase lock (sync) that inverts wave direction instead of restarting the cycle etc.) but it's quite decent and needs some quality pars (at least 2 matched npn for expo-converter, 2 pnp for ota, high quality capacitor for intergrator parts).

@ Bergfotron:
Could you answer how many octaves can your triangle vco keep hold of?
People are reporting that their 258 by M. Verbos tracks up to 3 octaves which is rather not good (esp. when using at woodwind waveshapers).


I would like you all to pay attention to one more interesting osc - the Basic VCO based on 4027 - I would like to admit that Bergfors is one of the few people in the world :woah: who repeated this ARP VCO (after AnalogMetropolis and one of my friends as well :mrgreen: ) - this core doesn't need matching and doesn't requires rare parts (a few jfets and some transistors arrays and 2k tempco)

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Bergfotron
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Post by Bergfotron » Tue Aug 30, 2011 8:32 am

ultrashock wrote:@ Bergfotron:
Could you answer how many octaves can your triangle vco keep hold of?
People are reporting that their 258 by M. Verbos tracks up to 3 octaves which is rather not good (esp. when using at woodwind waveshapers).
I fired it up and measured the frequencies below, when the CV was increased in 1 volt steps:

50
100
200
401
803
1617
3270
6601
13150
26110

I haven't tuned it in a couple of years, so maybe the tracking could be improved further by adjusting the oct/V trimmer.

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Post by forbin » Fri Jun 07, 2013 12:27 am

Kept waiting to see if anybody had built it! Anyway have plowed on myself and it is starting to come to life! I put a picture here: http://forbinthesynthesizer.blogspot.com of progress so far and will keep a list of tweeks to the documentation that may be of some help to others... It is quite challenging and had some :deadbanana: along the way but mostly my stuff ups...

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Post by monstrinho » Fri Jun 07, 2013 11:40 am

This may be a silly question (if so, my apologies), but is there anything preventing using the woodwind waveshaper as a standalone device with any waveform from any VCO? Or does it function in such a way that it needs to be wired directly to the VCO core?

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Post by thermionicjunky » Fri Jun 07, 2013 3:11 pm

monstrinho wrote:This may be a silly question (if so, my apologies), but is there anything preventing using the woodwind waveshaper as a standalone device with any waveform from any VCO? Or does it function in such a way that it needs to be wired directly to the VCO core?
It uses the square wave, so add a comparator if you want to use any waveform. I'm planning on doing a module based on the WW shaper, along with the other shapers in this VCO.

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Post by murray » Fri Jun 07, 2013 5:58 pm

Gathering parts and planning to build the "complex vco" in a buchla format.. never attempted such a complex module, but everything to know is provided!

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Post by Luka » Fri Jun 07, 2013 7:33 pm

If anyone can get it going forbin you can
Looking forward to hearing your version

I always wanted this one but i have enough vcos for my system. Id be intersted in a standalone waveshaper section.

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Post by keninverse » Fri Jun 07, 2013 8:36 pm

I too would love to see a standalone project for all the wave shaping on this module. There's ome really interesting sounds from coming from it. The woodwind portion doesn't seem too complex to make a smaller board but having all the wave shaping capabilities on one standalone board would be awesome.

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Post by Nantonos » Fri Jun 07, 2013 9:19 pm

The woodwind shaper looks interesting, as does the other shaper in particular the "evens" waveform. For modular use, a standalone shaper would probably be more popular than a combined VCO and shaper.

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