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Ilanode
Joined: Sep 14, 2007 Posts: 80 Location: Berlin/FRG
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Posted: Sat Jul 12, 2008 6:09 am Post subject:
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Fonik, any chances that there will be PCBs for the LPG-project? |
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fonik
Joined: Jun 07, 2006 Posts: 3950 Location: Germany
Audio files: 23
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Posted: Sat Jul 12, 2008 8:21 am Post subject:
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Ilanode wrote: | Fonik, any chances that there will be PCBs for the LPG-project? |
no, not from me. i won't do that since this is peter grenader's circuit. actually he's making money from it now. he once published his circuit on the web so i did a DIY layout and that's it. _________________
cheers,
matthias
____________
Big Boss at fonitronik
Tech Buddy at Random*Source |
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Fernando
Joined: Dec 30, 2006 Posts: 286 Location: Barcelona & Emporda, Spain
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Posted: Tue Jul 15, 2008 6:42 am Post subject:
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zthee wrote: | I just started to build 2 of these, but with the old documentation
Just need the vactrol and the usual wires to pots and stuff like that. Hope to be done within a week or so!
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I love your panels
very inspiring, thank you |
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vtl5c3
Joined: Sep 08, 2006 Posts: 425 Location: PDX
Audio files: 13
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Posted: Wed Jul 23, 2008 9:06 am Post subject:
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Does anyone have a mouser part number for a good switch for this module?
I've been playing with my quad LPG* a lot this week and am completely in love with its sound. It gives my modular a very warm, accoustic instrument quality that it's never had before.
*(different layout, too many parts - that's why I want to the Fonik version) |
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fonik
Joined: Jun 07, 2006 Posts: 3950 Location: Germany
Audio files: 23
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Posted: Wed Jul 23, 2008 9:15 am Post subject:
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vtl5c3 wrote: | Does anyone have a mouser part number for a good switch for this module? |
actually not.
i was thinking of doing another version with a voltage controlled switch? _________________
cheers,
matthias
____________
Big Boss at fonitronik
Tech Buddy at Random*Source |
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ericcoleridge
Joined: Jan 16, 2007 Posts: 889 Location: NYC
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Posted: Wed Jul 23, 2008 11:17 am Post subject:
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That would be really cool Fonik. It would just be a button to toggle through, with LED indicators for mode? |
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ericcoleridge
Joined: Jan 16, 2007 Posts: 889 Location: NYC
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Posted: Wed Jul 23, 2008 11:21 am Post subject:
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vtl5c3 wrote: | Does anyone have a mouser part number for a good switch for this module? |
I had a rather hard time sourcing this switch also. The problem is, I couldn't find them at an affordable price. I finally took my search to e-bay and got them very inexpensively. But some of the distributors were charging as much as $20 a piece!
vtl5c3 wrote: |
I've been playing with my quad LPG* a lot this week and am completely in love with its sound. It gives my modular a very warm, accoustic instrument quality that it's never had before. |
I completely agree. There's something alchemical about this circuit. |
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zthee
Joined: Feb 20, 2008 Posts: 414 Location: Stockholm
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Posted: Wed Jul 23, 2008 11:41 am Post subject:
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fonik wrote: | vtl5c3 wrote: | Does anyone have a mouser part number for a good switch for this module? |
actually not.
i was thinking of doing another version with a voltage controlled switch? |
Using a 4016 instead?
That would be great!
Atleast you'll save a few $$ on it. (The switches I bought were really expensive... and they were the only ones I could find..)
I'm just about to finish my modular, and I'm really glad I've got two 292 in it! |
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vtl5c3
Joined: Sep 08, 2006 Posts: 425 Location: PDX
Audio files: 13
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Fernando
Joined: Dec 30, 2006 Posts: 286 Location: Barcelona & Emporda, Spain
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Posted: Thu Jul 24, 2008 2:17 am Post subject:
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IIRC eBay's HKSuperseller have them, let me check where did I bought them for shure and if they were on/on/on or on/off/on, but they should have both... |
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Ilanode
Joined: Sep 14, 2007 Posts: 80 Location: Berlin/FRG
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Posted: Thu Jul 24, 2008 3:12 am Post subject:
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zthee wrote: | (The switches I bought were really expensive... and they were the only ones I could find..) |
Do they work fine since they have only 6 pins while the LPG wants 9? |
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fonik
Joined: Jun 07, 2006 Posts: 3950 Location: Germany
Audio files: 23
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Posted: Thu Jul 24, 2008 3:25 am Post subject:
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3 pole, on-off-on - that would mean 3 lugs/pins for the three inputs (3-pole) and 6 lugs for the outputs (2 for each pole). so you need 9 lugs/pins.
you want to switch three independent signals to two different outputs each... _________________
cheers,
matthias
____________
Big Boss at fonitronik
Tech Buddy at Random*Source |
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Fernando
Joined: Dec 30, 2006 Posts: 286 Location: Barcelona & Emporda, Spain
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Posted: Thu Jul 24, 2008 5:59 am Post subject:
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guitar parts suppliers are a good place to get both this on-off-on and the on-on-on needed for another version of the LPG |
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doctorvague
Joined: Mar 14, 2007 Posts: 281 Location: new mexico
Audio files: 2
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Ilanode
Joined: Sep 14, 2007 Posts: 80 Location: Berlin/FRG
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ericcoleridge
Joined: Jan 16, 2007 Posts: 889 Location: NYC
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Posted: Sat Aug 02, 2008 11:01 pm Post subject:
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ericcoleridge wrote: | That would be really cool Fonik. It would just be a button to toggle through, with LED indicators for mode? |
Is this the idea Fonik? Instead of using an expensive switch, you'll incorporate CMOS switching with a toggle button for mode (and possibly LEDs to indicate status)? That would be pretty neat. I might have to design a new module for this update. |
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Coriolis
Joined: Apr 11, 2005 Posts: 616 Location: Stilling, Denmark
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Posted: Sat Aug 02, 2008 11:52 pm Post subject:
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Quote: | Instead of using an expensive switch, you'll incorporate CMOS switching with a toggle button for mode |
I believe that is how it is done in the mark verbos clone...
C _________________ Some Rubber Stamp Sound Effects - and other sound effects |
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Ilanode
Joined: Sep 14, 2007 Posts: 80 Location: Berlin/FRG
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Posted: Thu Aug 14, 2008 1:53 am Post subject:
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For some reason I’m able to include a bug even into the smallest circuit. Now it’s the LPG. The PCB has been made by a semi-professional supplier via ebay. It just looks fine so I’m sure the mistake is on my side.
Two of the three modes are working fine. However the LPF remains silent while the Resonance pot has no effect at all. The chip works fine since probing each pin has given the results expected. So I guess the fault is somewhere around the switch however the wiring itself seems to be just fine.
Any help is highly appreciated. TIA, Ingo |
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fonik
Joined: Jun 07, 2006 Posts: 3950 Location: Germany
Audio files: 23
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Posted: Thu Aug 14, 2008 11:53 am Post subject:
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hello ingo,
the fact that you built it with the resonnance option and that the lowpass is not working indicates that something might be wrong wth exactly the resonnance circuit. recheck all the wiring.
the resonnance option is not tested, yet. i am not sure if someone built it in yet. it is the implementation of a guessing i read in this forum somewhere...
since the resonannce option is available for the lowpass mode only, i would recommend to omitt it for now, just to be sure everything else is working fine. (you could just cut the wires and bridge jumper 1 by connecting the appropriate wires with aligator clips.)
hope that helps.
before doing so, recheck all the wiring again. _________________
cheers,
matthias
____________
Big Boss at fonitronik
Tech Buddy at Random*Source |
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Ilanode
Joined: Sep 14, 2007 Posts: 80 Location: Berlin/FRG
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Posted: Thu Aug 14, 2008 12:17 pm Post subject:
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That's it! It works fine without the resonance mod! Could it be that the mod itself is faulty? Someone from a German forum has a similiar prob: LPF-mode almost inaudible.
Sine I checked the wiring various times before posting I suspect the resonance mod is buggy.
Anyhow, thanks for your assistance and making the pcb layout available. Highly appreciated! |
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fonik
Joined: Jun 07, 2006 Posts: 3950 Location: Germany
Audio files: 23
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Posted: Thu Aug 14, 2008 1:58 pm Post subject:
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so you've been a beta tester - sorry.
found the source of the modification. mark verbos wrote:
Quote: | If you increase the gain going through the .0047 uF feedback capacitor, you will get resonance. In practice, this can be done by adding an opamp gain stage between the ouput opamp and that capacitor. Just intercept the line between the switch and the .0047uF cap. Send the switch side into the + input and put a 50k pot with the wiper to the - input, the CCW end to the ouput and the CW side thru a 50k resistor to ground. Send the output of that opamp through the .0047uF cap.
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did i misunderstood his suggestions? can't see why. anyone? _________________
cheers,
matthias
____________
Big Boss at fonitronik
Tech Buddy at Random*Source |
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guitarfool
Joined: Feb 26, 2007 Posts: 160 Location: Maryland
Audio files: 8
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Posted: Thu Aug 14, 2008 4:11 pm Post subject:
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fonik wrote: | the resonnance option is not tested, yet. i am not sure if someone built it in yet. |
It's tested I was going to build a classic LPG using an older layout, and yours came out right after I'd finished the panels. So I built my first one without the feedback.
I've since built a second one WITH the feedback option, and it is wonderful. Now I have to do a new panel, so if anyone wants a couple of Moog/Dotcom format panels for a classic LPG...
Anyway, there is absolutely nothing wrong with the schematic or layout.
If yours works without the option (jumper between "A" amd "B" on JP1), then the switch is probably okay. In this configuration, JP2, R18 and P2 are not needed. For the resonance option, point "A" of JP1 is jumpered to point "A" of JP2, and point "B" of JP1 is jumpered to point "B" of JP2. Maximum resonance occurs when the wiper of P2 is at the R18 end of the pot. At the other end, feedback is unity and the circuit behaves exactly like one without the resonance option. I tried both of mine (the first one without the option) and the second one side by side in the same patch, and with the resonance set to minimum, they sounded identical. I hope to get a sound file up this weekend to demonstrate.
With the resonance control above about two thirds, it will self resonate.
The resonance control only affects the LP mode: it does nothing in Gate or Both modes.
I heartily recomend adding it |
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guitarfool
Joined: Feb 26, 2007 Posts: 160 Location: Maryland
Audio files: 8
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Posted: Thu Aug 14, 2008 4:13 pm Post subject:
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fonik wrote: | did i misunderstood his suggestions? can't see why. anyone? |
No. You did good |
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neandrewthal
Joined: May 11, 2007 Posts: 672 Location: Canada
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Posted: Thu Aug 14, 2008 10:10 pm Post subject:
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Every single LPG I've seen has no CV attenuators. Is there just no need for them in the way it is typically used, or is everyone using external attenuators? _________________ " I went through quite a few trannies til I found one I liked" - Wild Zebra |
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cbm
Joined: Oct 25, 2005 Posts: 381 Location: San Francisco
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Posted: Thu Aug 14, 2008 10:21 pm Post subject:
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neandrewthal wrote: | Every single LPG I've seen has no CV attenuators. Is there just no need for them in the way it is typically used, or is everyone using external attenuators? |
I'm using cascaded LPG sections, one set to filter and another set to amplitude. I use external attenuators on the filter LPG.
-C _________________ Chris Muir
http://www.eardrill.com <– My jobby (more than a hobby, less than a job) |
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