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nicolas3141
Joined: May 25, 2007 Posts: 185 Location: Christchurch, New Zealand
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Posted: Sun Feb 22, 2009 3:31 am Post subject:
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LetterBeacon wrote: | nicolas3141 wrote: | The interest is encouraging me to tidy up and share more of my modules. |
Please do! |
My super simple LFO design is up and I will also post a voltage controlled LFO in the next few days:
http://electro-music.com/forum/topic-32372.html
Cheers,
Nicolas |
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rubendelacosta
Joined: Dec 25, 2005 Posts: 153 Location: lisbon
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Posted: Mon Feb 23, 2009 9:19 am Post subject:
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got your adsr working and i'm planning to build a few more
can't wait to see you voltage controlled lfo! |
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Pehr
Joined: Aug 14, 2005 Posts: 1307 Location: Björkvik, Sweden
Audio files: 2
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nicolas3141
Joined: May 25, 2007 Posts: 185 Location: Christchurch, New Zealand
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nicolas3141
Joined: May 25, 2007 Posts: 185 Location: Christchurch, New Zealand
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Posted: Fri Mar 06, 2009 4:07 am Post subject:
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I have been thinking about the +/-15V question. It might be okay, but you may need to put in an additional protection diode for the transistor. At +/-9V supply it gets subjected to up to 7V of reverse voltage which it seems to handle in practice, but is actually slightly in excess of what the datasheet recommends. With higher power supply voltages the extra reverse voltage might be too much for it.
Cheers,
Nicolas |
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camelneck
Joined: Sep 27, 2008 Posts: 68 Location: KY (USA)
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Posted: Wed Apr 01, 2009 12:18 am Post subject:
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nicolas3141 wrote: | Here's my ultra simple ADSR that can also retrigger itself to behave like an LFO . . . |
Nicolas,
I really like this simple one chip design, and may build several of these myself. I have 3 questions I'd like to ask just in case you happen to know the answers.
1) Using the same component values that are shown on the schematic, what is the maximum attack time, decay time, and release time you get? (It don't have to be exact since the pot tolerance can effect this by 10 to 20%.)
2a) In regards to the trigger switch and the diode it is connected to, what is the minimum voltage that must be applied to the diode (cathode end) in order for the ADSR to re-trigger?
2b) Instead of the retrigger out signal, have you ever tried to apply a 8V - 12V "keyboard trigger" signal to the cathode of the diode instead?
I think this would allow this ADSR to work with keyboards that have both "gate" and "trigger" outputs provided the trigger pulse is wide enough. (Otherwise, the trigger input would need some processing.)
If only a gate input is applied to the ADSR, it would function in "single-trigger mode" (with the 10nF cap providing the trigger signal each time the gate signal is applied.). On the other hand, if both a gate and trigger input are applied to the ADSR, it could be "multi-triggered" (the trigger signal could re-trigger the ADSR independent of the gate signal.)
Better yet, the SPST Switch could be replaced with a DPDT switch (on-off-on) that could be labeled something like this: Multi-Trigger/Single Trigger/Re-trigger. In the first position, "multi-trigger", the diode is connected to the trigger input. In the third position, "re-trigger", the diode is connected to the "retrigger" out signal. In the center position, "single trigger", the diode receives no input signal.
David |
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nicolas3141
Joined: May 25, 2007 Posts: 185 Location: Christchurch, New Zealand
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Posted: Thu Apr 02, 2009 2:22 am Post subject:
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camelneck wrote: |
1) Using the same component values that are shown on the schematic, what is the maximum attack time, decay time, and release time you get? (It don't have to be exact since the pot tolerance can effect this by 10 to 20%.) |
On my prototype the attack ranges from very quick through to nearly 10s. Decay is similar. Release can extend out to about 30s. Fairly typical sort of values I think. For some things like handclap type percussion or space music type pads you might want faster or slower than this can do, but not for most things and adjusting a few resistors you could move the range anyway.
Cheers,
Nicolas |
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nicolas3141
Joined: May 25, 2007 Posts: 185 Location: Christchurch, New Zealand
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Posted: Thu Apr 02, 2009 2:40 am Post subject:
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camelneck wrote: |
2a) In regards to the trigger switch and the diode it is connected to, what is the minimum voltage that must be applied to the diode (cathode end) in order for the ADSR to re-trigger?
2b) Instead of the retrigger out signal, have you ever tried to apply a 8V - 12V "keyboard trigger" signal to the cathode of the diode instead?
I think this would allow this ADSR to work with keyboards that have both "gate" and "trigger" outputs provided the trigger pulse is wide enough. (Otherwise, the trigger input would need some processing.)
If only a gate input is applied to the ADSR, it would function in "single-trigger mode" (with the 10nF cap providing the trigger signal each time the gate signal is applied.). On the other hand, if both a gate and trigger input are applied to the ADSR, it could be "multi-triggered" (the trigger signal could re-trigger the ADSR independent of the gate signal.)
Better yet, the SPST Switch could be replaced with a DPDT switch (on-off-on) that could be labeled something like this: Multi-Trigger/Single Trigger/Re-trigger. In the first position, "multi-trigger", the diode is connected to the trigger input. In the third position, "re-trigger", the diode is connected to the "retrigger" out signal. In the center position, "single trigger", the diode receives no input signal.
David |
The triggering voltage pumped into the diode needs to be at least 0.7V higher than the output voltage of the ADSR at that point in time (and needs to last about half a millisecond or longer). So to guarantee success it needs to 0.7V higher than the maximum output voltage which is determined by the upper trigger level of the schmitt trigger formed by the central op-amp. With +/-9V supply and the two 1M resistors shown in my drawing that means about 4.5V would do it. With the +/-15V and the R4 and R5 values shown in Matts drawing you would need over 10V to guarantee it.
Either way the schmitt trigger on the upper left that we use when in LFO mode will do the trick as its output goes to within a couple of volts of the supply.
So if you want to connect it the trigger output of a keyboard or sequencer it should work too as long the pulse voltage is something approaching the +ve supply voltage and the pulse width is somewhere around the millisecond range.
Cheers,
Nicolas |
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Dego
Joined: Apr 22, 2008 Posts: 139 Location: Sweden
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Posted: Thu May 14, 2009 6:16 am Post subject:
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I am building this project now (ADSR based on LM324).
I will let you now how it works.
Nicolas, did you design a 9 volt VCA as well? |
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nicolas3141
Joined: May 25, 2007 Posts: 185 Location: Christchurch, New Zealand
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Posted: Thu May 14, 2009 1:35 pm Post subject:
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Hope it goes well for you.
Yes, I have filter, VCA and sample/hold/glide designs based around LM13600/13700. But I have been a bit too busy just recently and haven't had time to tidy up the drawings. Will do when I get the chance.
Cheers,
Nicolas |
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nicolas3141
Joined: May 25, 2007 Posts: 185 Location: Christchurch, New Zealand
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Posted: Sat Nov 14, 2009 5:17 pm Post subject:
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Hi smidirin
It should start at 0V, go up to a few V, then settle back to 0V again. For 0-10V output you will need +/-15V power supply or at least +/-12V. LM348 or TL074 are better choices than LM324 at the higher voltage.
Check that the negative opamp power connection is to -15V. Check that all the 0V points in the circuit diagram are properly connected to 0V. And double check the connection of the PNP transistor for wrong way round, dry joint, etc. Hope you find the problem.
Cheers,
Nicolas
> gday,
> over the weekend i have built 2 of your superbly simple lm324 adsr's. Cool
> first one i used tl074 cos i couldnt find my 324 stash.
> after some confusion with the pot connections i got it working.
> i used 2n3906 pnp and also fonik's 390k to up the output.
> the strange thing is i get an output offset about +6v with about 4v envelope.
> so i built another one, i found a lm348 lying around so i used that.
> all same parts as before. and same result.
> is this a offboard wiring issue? or choice of ic? or part of the design? i
> want to use these 2 with a dualvca i built not long ago. lookin for 0-10v swing.
> forgot, i have added the led indicator form fonik schematic as well.
>
> thanks nicolas! |
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smidirin
Joined: May 01, 2007 Posts: 14 Location: analogfx.studio
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Posted: Sun Nov 15, 2009 12:21 am Post subject:
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hey, thanks again..
so..
Quote: | For 0-10V output you will need +/-15V power supply or at least +/-12V. LM348 or TL074 are better choices than LM324 at the higher voltage.
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yeah forgot to mention it is on +/-15V.
2n3906 is double checked for orientation.
opamp is pwr'd.
all 0v are grounded.
both units slightly diff layout (strip vs. proto) with exactly same thing happening though.
so to confirm: offboard i have 2 diodes (1 on attack, 1 on sustain) & 3 resistors (1 on attack, 2 on sustain).
did i miss somethin???
didn't think i could make the same mistake twice.
s. |
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nicolas3141
Joined: May 25, 2007 Posts: 185 Location: Christchurch, New Zealand
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Posted: Mon Nov 16, 2009 12:48 am Post subject:
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smidirin wrote: | yeah forgot to mention it is on +/-15V.
2n3906 is double checked for orientation.
opamp is pwr'd.
all 0v are grounded.
both units slightly diff layout (strip vs. proto) with exactly same thing happening though. |
At the end of the cycle when it should be decaying away to zero, check the output voltage of the opamp handling the gate input (lower left in the diagram) and the flip-flop opamp (in the middle of the diagram). At the end of the cycle they should both be outputting as negative as they can, about -12V. If either of them is outputting a positive voltage that is a problem and you need to review the resistor values connected to the input of that opamp. Remember I worked out the resistor values for +/-9V supply so at +/-15V there may be tweaks required.
And check the voltages on the three legs of the transistor. Remember the 2N3906 has its legs the opposite way around from the BC559. Should be something like: C = zero volts, E = zero or just a few millivolts positive, B = somewhat negative, maybe about a volt or so.
Cheers,
Nicolas |
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slacker
Joined: Nov 18, 2007 Posts: 301 Location: England
Audio files: 11
G2 patch files: 1
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Posted: Mon Nov 16, 2009 6:48 am Post subject:
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nicolas3141 wrote: | Remember I worked out the resistor values for +/-9V supply so at +/-15V there may be tweaks required.
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If it's any help I built mine with the standard resistor values and it works fine at +/-15 volts. The only change I made was to replace the 1M resistor in the feedback loop of the middle opamp with a 470k to get the peak output up to about 10 volts.
If you like I can measure the voltages off mine if that will help with the debugging. |
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smidirin
Joined: May 01, 2007 Posts: 14 Location: analogfx.studio
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Posted: Mon Nov 16, 2009 5:52 pm Post subject:
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@slacker, that would be useful to me.
i built another (my 3rd) on a breadboard last night.
just gotta find some more pots and hook up the power.
previous layouts are both way too tight to measure (no gator clips here).
Quote: | middle opamp with a 470k to get the peak output up to about 10 volts.
If you like I can measure the voltages off mine if that will help with the debugging. |
i used 390k like fonik but yeah same here.
i measured 6.43v instead of zero! peak between 9.2 & 9.4.
@nicolas
Quote: | Hope you find the problem.
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not given up yet! pesky though..
s. |
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smidirin
Joined: May 01, 2007 Posts: 14 Location: analogfx.studio
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Posted: Tue Nov 17, 2009 3:28 pm Post subject:
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well,
i haven't fixed the first 2 but the breadboard worked first go.
i reused the same pots with their parts and wiring so it's looking like a botched resistor value in the others.
at least i can take some voltages and compare resistor stripes, then should be sorted.
you can get some nice shapes outta this little adsr!
thanks all. |
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smidirin
Joined: May 01, 2007 Posts: 14 Location: analogfx.studio
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Posted: Tue Nov 24, 2009 1:31 am Post subject:
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solved.
C&E were the culprit..
on the indicatorLED tranny
had checked everything else x3
s. |
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rehibot
Joined: Feb 27, 2010 Posts: 2 Location: Australia
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Posted: Tue Apr 20, 2010 5:23 am Post subject:
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Quote: | It might be okay, but you may need to put in an additional protection diode for the transistor |
Is this what you meant Nicolas?
----image deleted-----
Edit: deleted incorrect diagram to avoid any possible confusion. (I had the diode drawn in anti-parallel to the transistor's BE junction) Last edited by rehibot on Tue Apr 20, 2010 6:52 pm; edited 1 time in total |
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nicolas3141
Joined: May 25, 2007 Posts: 185 Location: Christchurch, New Zealand
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rehibot
Joined: Feb 27, 2010 Posts: 2 Location: Australia
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Posted: Tue Apr 20, 2010 6:53 pm Post subject:
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Thanks Nicolas, I appreciate your work |
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adamon
Joined: May 15, 2009 Posts: 96 Location: Lawrence Kansas
Audio files: 3
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Posted: Wed May 19, 2010 10:35 pm Post subject:
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Any thoughts on getting an ADSR like this to run on a +/-4.5V (0-9V) supply? I've been dead set on keeping my system running on a 0-9V supply, but I'm really starting to want/need some envelopes! The simplicity of Nicolas' stuff is very appealing, but I don't have the know-how to figure out if this could work or what would need to be changed if it is possible...
One thing I should mention is that I'd like to just drive an LED only at the output; I'll just be driving the LED end of a vactrol with this, so I'm not too concerned with the output level. _________________ www.soundcloud.com/adamon |
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nicolas3141
Joined: May 25, 2007 Posts: 185 Location: Christchurch, New Zealand
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adamon
Joined: May 15, 2009 Posts: 96 Location: Lawrence Kansas
Audio files: 3
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Posted: Thu May 20, 2010 10:25 am Post subject:
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Wow, that looks great Nicolas! Yes, I'm planning on using a virtual ground. I figured the circuit should run fine but was concerned with what would be coming out of it. Looks like the transistor should give me enough control over it though. Will my inputs need to be adjusted as well?
thanks for your help Nicolas, it is greatly appreciated! _________________ www.soundcloud.com/adamon |
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oozitron
Joined: Apr 02, 2007 Posts: 38 Location: USA
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Posted: Wed Feb 02, 2011 10:13 am Post subject:
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I've built this ADSR on protoboard, and now that I have Q1 oriented the correct direction (!) it's behaving much better, but still not right.
I think it might have to do with how the pots are wired. I've been going by Fonik's very nice schematic, but then when I look at his PCB picture I get confused.
The Decay pot wiper (marked pin #3?) connects to LM324 Pin 12. But on the PCB image it appears that the Decay wiper connects to the Diode.
I guess I'm confused by the [1, 2, 3] that identify the pins on the pots. Shouldn't the wiper (center) pin always be #2?
thanks in advance!
Drew |
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cypher
Joined: Dec 08, 2010 Posts: 12
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Posted: Wed Feb 09, 2011 12:12 am Post subject:
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Hi all!
Please, I am looking for a very simple design ADSR with current only 5-6 V DC supply. Please can someone give some advice, which of the design can be usable on such a such low (5V) power supply (preferably 555 based one)?
Thanks very much for any advise. |
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