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The Synthasystem Discussion and Appreciation Thread |
Rod Serling Fan Club aquatic hitchhiker
Joined: 14 Dec 2009 Last Visit: 21 May 2013
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Posted: Sun Mar 04, 2012 1:20 pm Post subject: |
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| diophantine wrote: | | Rod Serling Fan Club wrote: | | diophantine wrote: |
I have also finished building a Triple EG - EGs 1 & 3 work great, but EG2 seems busted... I need to debug more, but I think it is a bad cap. Anyhow, it seems to be a really cool module!
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Odd I have the same problem with mine. Please let me now what you find. I am curious to see how your 3eg panel w/bananas since there is some normalization. |
Curiouser and curiouser... how does your EG2 behave? Mine just outputs a gate, as if Attack=0 & Decay=0. The level is affected by the Duration Level pot, but the Attack and Decay pots don't do anything (nor do any of the switches).
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It's been a while since I played with it. That system isn't set up at the moment but I've started working on it again. I will let you know when I get back to it. _________________ DIY panels and PCBs for Buchla and Euro format: http://synthpanels.blogspot.de/
youtube channel: http://www.youtube.com/user/MrPalebluedot |
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Rod Serling Fan Club aquatic hitchhiker
Joined: 14 Dec 2009 Last Visit: 21 May 2013
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Posted: Sat Mar 10, 2012 9:05 pm Post subject: Re: The Synthasystem Discussion and Appreciation Thread |
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| Isaiah wrote: |
VCO - LINEAR FM
I spoke to Dr. Sketch-n-Etch a while ago about the possibility of implementing Linear FM on the Synthasystem VCOs.
Referring to the VCO A schematic:
| Dr. Sketch-n-Etch wrote: | I'm not completely sure I understand the functioning of this oscillator completely, but I'm pretty sure that I know how to apply Linear FM.
Basically, you should try sending an attenuated signal through an 8.2k resistor in parallel with R14 into the common emitters of Q6. I believe that R14 sets the servo current into the VCO core, so modulating this current should give you Linear FM.
Give it a try and let me know how it works. |
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I got back to completing my VCO and thought I'd try the lin fm mod. Just to make sure I understand: Just solder another 8.2k from the input jack to the point on the PCB where R14 connects to the emitters of Q6? _________________ DIY panels and PCBs for Buchla and Euro format: http://synthpanels.blogspot.de/
youtube channel: http://www.youtube.com/user/MrPalebluedot |
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Isaiah Ultra Wiggler
Joined: 02 Jun 2010 Last Visit: 21 May 2013
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Posted: Sun Mar 11, 2012 4:56 am Post subject: |
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Yes, connect to the junction where R14 joins the Emitters of Q6.
Could also try decoupling the input signal with a capacitor first too. AC/DC Lin FM.
I'd maybe connect a pot as a variable resistor in series with the 8.2K.
Though a variable potential divider might work too, I just have a feeling that the Lin FM input should be 'floating' like the Var. CV input on the VCO.
Very interested to hear how you get on with it!
Hope it works well! |
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Isaiah Ultra Wiggler
Joined: 02 Jun 2010 Last Visit: 21 May 2013
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Posted: Fri Mar 16, 2012 3:35 am Post subject: |
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RSFC
Did you have any joy with the Lin FM mod? |
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MechaSeb Super Deluxe Wiggler
Joined: 02 Apr 2010 Last Visit: 21 May 2013
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Posted: Fri Mar 16, 2012 6:13 am Post subject: |
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Just received two of my big orders. One from David himself and the other from FPE. David is really professional and it's a pleasure to deal with. First time i receive something from FPE too but it blew my mind how the front panel are quality made. Really happy for the moment !
Wil post some ugly pics tomorrow just for fun.
Edit : here they are
| Isaiah wrote: | RSFC
Did you have any joy with the Lin FM mod? |
would like to know too  _________________ Drone/Dark Ambient EPs : TheSunAlsoRises
Random tracks & wip |
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Rod Serling Fan Club aquatic hitchhiker
Joined: 14 Dec 2009 Last Visit: 21 May 2013
   Posts: 3431 Location: Germany
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Posted: Fri Mar 16, 2012 9:40 am Post subject: |
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| MechaSeb wrote: |
| Isaiah wrote: | RSFC
Did you have any joy with the Lin FM mod? |
would like to know too  |
I added the mod but I haven't tried it yet. The module wired and ready to go but I am missing the trimmer for the high-freq tracking PCB. I might calibrate this weekend and install the hi-freq tracking later. I'll let you know. _________________ DIY panels and PCBs for Buchla and Euro format: http://synthpanels.blogspot.de/
youtube channel: http://www.youtube.com/user/MrPalebluedot |
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Isaiah Ultra Wiggler
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Posted: Fri Mar 16, 2012 11:41 am Post subject: |
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| MechaSeb wrote: | | Just received two of my big orders. One from David himself and the other from FPE. David is really professional and it's a pleasure to deal with. First time i receive something from FPE too but it blew my mind how the front panel are quality made. Really happy for the moment ! |
Wowee zowee, congratulations!
That'll keep you busy for a while!
I couldn't agree more about David, such a gentleman. |
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Isaiah Ultra Wiggler
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Posted: Sat Mar 17, 2012 9:03 am Post subject: |
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| Rod Serling Fan Club wrote: | | MechaSeb wrote: |
| Isaiah wrote: | RSFC
Did you have any joy with the Lin FM mod? |
would like to know too  |
I added the mod but I haven't tried it yet. The module wired and ready to go but I am missing the trimmer for the high-freq tracking PCB. I might calibrate this weekend and install the hi-freq tracking later. I'll let you know. |
Exciting!
How did you decide to implement the mod? |
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e-grad Super Deluxe Wiggler
Joined: 07 Oct 2008 Last Visit: 21 May 2013
    Posts: 2235 Location: Berlin
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Posted: Sat Mar 17, 2012 9:12 am Post subject: |
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Any first hand experiences on the Triple EG?
How does it compare to function generators such as the Buchla 281? _________________ elektrograd |
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diophantine Super Deluxe Wiggler
Joined: 10 Jan 2011 Last Visit: 14 May 2013
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Posted: Sat Mar 17, 2012 8:35 pm Post subject: |
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| e-grad wrote: | Any first hand experiences on the Triple EG?
How does it compare to function generators such as the Buchla 281? |
I actually just finished debugging the second EG earlier this afternoon (was a busted pad!). I haven't played around with a whole lot, but a bit.
It is something of a hybrid between a traditional ADSR and a AD/AR, but with a number of extra & interesting features. Not sure if I'd compare it to a 281, but they do both allow AD and AR (though AR just on EG3), and you can combine envelopes.
Triple EG allows for more ADSR-style envelopes, but with less knob-fiddling than traditional ADSRs. It also allows a fixed sustain time on EG3, and delays on EGs 2 & 3. The damp & qtn functions also allow for the creation of interesting envelopes.
281 has the quadrature mode, CV attack/decay, repeat mode, and trigger output.
I think they're both interesting & worthwhile! I am considering building both into my MU modular, even.
It has been a while since I've seen it, but I seem to recall that in this video David did shows most all the features of the Triple EG:
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e-grad Super Deluxe Wiggler
Joined: 07 Oct 2008 Last Visit: 21 May 2013
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Posted: Mon Mar 19, 2012 9:16 am Post subject: |
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Thanks!
I've still some 281 in the pipeline and have finished one 281 which is a blast. At least for the kind of stuff I do.
However, the Triple EG seems to add some really unique features which would blend nicely with my system. ATM I must resist but guess I'll end up with one Triple EG.
Nice work, David! Thanks for making it available. _________________ elektrograd |
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Rod Serling Fan Club aquatic hitchhiker
Joined: 14 Dec 2009 Last Visit: 21 May 2013
   Posts: 3431 Location: Germany
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Posted: Tue Mar 20, 2012 12:44 pm Post subject: |
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I wonder if there would be any interest in a group buy of MPC euro panels for the synthasystem? Right now my panels are etched but I wouldn't mind some professional panels if there was enough interest to make it feasible.
They would be the standard euro-silver (aluminum) color with black print. This is also how the earlier synthasystems looked. _________________ DIY panels and PCBs for Buchla and Euro format: http://synthpanels.blogspot.de/
youtube channel: http://www.youtube.com/user/MrPalebluedot |
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Isaiah Ultra Wiggler
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Posted: Tue Mar 20, 2012 1:05 pm Post subject: |
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RSFC
Sounds like a good idea!
I'll post photos of my panels soon.
I used David's FPD files and had them machined by thebeast.co.uk on natural aluminium with black in-fill.
They look very handsome!
I have an alternative VCO A panel that I made using David's as my starting point.
It's much more like the early, silver Synthasystems.
I'll check with David, but I'm sure he won't mind me posting it. |
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Isaiah Ultra Wiggler
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Rod Serling Fan Club aquatic hitchhiker
Joined: 14 Dec 2009 Last Visit: 21 May 2013
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Posted: Wed Mar 21, 2012 6:06 pm Post subject: |
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| Isaiah wrote: | | Rod Serling Fan Club wrote: | | MechaSeb wrote: |
| Isaiah wrote: | RSFC
Did you have any joy with the Lin FM mod? |
would like to know too  |
I added the mod but I haven't tried it yet. The module wired and ready to go but I am missing the trimmer for the high-freq tracking PCB. I might calibrate this weekend and install the hi-freq tracking later. I'll let you know. |
Exciting!
How did you decide to implement the mod? |
I got started on trimming the VCO last night. I'm not done but I tried both FM inputs. I think the suggested resistor value is too high, it was FMing it through the linear mod but it was doing so as if it was very attenuated and there was no attenuation. exp FM and the oscillator in generaly sounds very nice so far. _________________ DIY panels and PCBs for Buchla and Euro format: http://synthpanels.blogspot.de/
youtube channel: http://www.youtube.com/user/MrPalebluedot |
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negativspace Manhattan Analog
Joined: 13 Apr 2010 Last Visit: 21 May 2013
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Posted: Thu Mar 22, 2012 5:38 am Post subject: |
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I really do love the VCO, David has it right that Nyle outdid himself with that design. Next to my Z3000 it's the one I go to most often and it never disappoints me. It tracks very well (even without the hi-freq tracking PCB, which I received after the fact and have not installed) and it always manages to sound alive no matter the waveform I use. The sawtooth cuts like a knife. I think I'll leave this one in my general Euro racks even when I pull the trigger on the standalone 9U I'm planning.
(I sent my case pattern off to my woodworker buddy a short while back so the wheels are finally turning... we bought some nice curly maple for it - exciting times!) _________________ Analogue Haven ∙ CTRL ∙ EquinoxOZ ∙ EFN ∙ Foxtone Music ∙ PostModular ∙ Schneidersbüro |
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Isaiah Ultra Wiggler
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Posted: Thu Mar 22, 2012 1:51 pm Post subject: |
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| Rod Serling Fan Club wrote: |
I got started on trimming the VCO last night. I'm not done but I tried both FM inputs. I think the suggested resistor value is too high, it was FMing it through the linear mod but it was doing so as if it was very attenuated and there was no attenuation. exp FM and the oscillator in generaly sounds very nice so far. |
Glad to hear your VCO is working and the Lin FM mod works (to some degree).
How does the Lin FM sound? |
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Rod Serling Fan Club aquatic hitchhiker
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Posted: Thu Mar 22, 2012 2:13 pm Post subject: |
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very attenuated
It’s hard to tell at that level. I need to finish adjusting trimmers and then get back to it. I might just try it without a resistor at all and work back from there. _________________ DIY panels and PCBs for Buchla and Euro format: http://synthpanels.blogspot.de/
youtube channel: http://www.youtube.com/user/MrPalebluedot |
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Rod Serling Fan Club aquatic hitchhiker
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bleeps Ultra Wiggler
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Posted: Sun Mar 25, 2012 12:38 pm Post subject: |
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I have some questions about the VCO-A. I'm looking for a solid DIY VCO for subtractive synthesis and I think this one will fit the bill. But, I want to slim down the panel or perhaps fit 2 or 3 behind a panel the same size as the traditional panel. Would I be missing out on any of the core features or patching potential if I did the following:
1) One output jack per waveform
2) Removed the waveform output attenuators
3) Reduced the number of CV inputs to one jack
I'm also curious about the Selective Inverter. That sounds like it could be fun to play with. |
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