|HOME| |DIY FAQ| |GEO FAQ| |Debugging Page| |Links| |Schematics| |Wiki| |Layouts Gallery| |STORE|
|AMPAGE| |GEOFEX| |AMZ|

Welcome, Guest. Please login or register.
Did you miss your activation email?
April 24, 2014, 06:25:46 PM
946650 Posts in 101637 Topics by 31731 Members
Latest Member: davizerrat
Home Help Login Register
DIYstompboxes.com  |  DIY Stompboxes  |  Building your own stompbox  |  Presenting the Qi-Gon : Envelope Filter/ Envelope Controlled Auto-Wah/Tremolo 0 Members and 1 Guest are viewing this topic. « previous next »
Pages: [1] 2 Go Down Print
Author Topic: Presenting the Qi-Gon : Envelope Filter/ Envelope Controlled Auto-Wah/Tremolo  (Read 3157 times)
drolo
Posts: 346


David R. (Brussels)


WWW
Presenting the Qi-Gon : Envelope Filter/ Envelope Controlled Auto-Wah/Tremolo
« on: January 18, 2013, 04:49:59 AM »





<a href="http://www.youtube.com/watch?v=JhZxvOCUoRI" target="_blank">http://www.youtube.com/watch?v=JhZxvOCUoRI</a>

Qi-Gon is an envelope filter/auto-wah with envelope controlled LFO speed/tremolo
As you can see it is based on the Lovetone Meatball, with modified envelope follower. I borrowed biasing idea from the Dr Quack, which allows using any kind of opamp.

It has a continuous sweep direction pot, similar to the Y-triggered Filter. I have no idea if it works the same way technically but the results are the same. I know that Mark Hammer is quite knowledgeable about the Y-Triggered and may be able to tell. I possess one but have never managed to understand that crazy circuit …
Turn to the left, the sweep goes up, then as you turn to the middle position the sweep gets weaker until there is no sweep at noon. Then the sweep gradually goes down as you turn to the right.

The filter LDR’s can be controlled either by the envelope follower or the LFO. When in LFO mode, the envelope follower controls the LFO speed. Depending on the sweep pot position, the attack will slow down the LFO speed or speed it up. Sweep pot and Intensity of the envelope follower change the speed interactively.

Apart from the usual frequency range selection, there is one position where the caps are replaced by a resistor and the feedback resistor upped for a quite convincing tremolo effect in LFO mode. Works similar to the Tremvelope from Pigtronix. In regards to the Meatball’s State Variable Filter, I changed the first opamp to be non-inverting, so that the low pass and high pass positions are in phase with the blended signal and only the bandpass is out of phase. (instead of the opposite on the meatball)

The pedal is using buffered bypass, so that the pedal connected in the send/return path is still active when in bypass mode. I modified the blend pot to blend between send/return signal and filtered signal instead of clean/filtered. Made more sense when using distortion.

I have also included an external expression control jack connected to the outer lugs of the sweep pot. I have only tested it with a manually turned pot as I have no expression pedal available, but it should work, provided the contacts of the expression pedal are isolated from ground.

Any suggestions or comments are more than welcome  Smiley

P.S. I did it on perfboard, YES, I am THAT crazy… icon_mad
Logged

"The inventor of the bagpipes was inspired when he saw a man carrying an asthmatic pig under his arm. Alas, the manmade sound never equalled the purity of the sound achieved by the pig."
H i t c h c o c k

www.davidrolo.com
http://drolo.bandcamp.com
~arph
Posts: 1362


Arnoud P. - The Netherlands


WWW
Re: Presenting the Qi-Gon : Envelope Filter/ Envelope Controlled Auto-Wah/Tremolo
« Reply #1 on: January 18, 2013, 05:24:56 AM »

Nice I like it.. sounds very good!
Logged

StripMagic: FREE, Vero, Perf and Breadboard layout software: http://www.friedair.com/stripmagic/start.jnlp  Opens and saves DIYLC files. Click to start!
digi2t
Posts: 2514


Burning stuff, since 2009.


Re: Presenting the Qi-Gon : Envelope Filter/ Envelope Controlled Auto-Wah/Tremolo
« Reply #2 on: January 18, 2013, 05:34:55 AM »

Quote
P.S. I did it on perfboard, YES, I am THAT crazy…

PHHHHHTTTTTTT!!!! Please... I'm doing an Infinitphase on vero.

http://www.diystompboxes.com/smfforum/index.php?topic=100664.0

You're a long way from crazy Mister.  icon_lol

Nice effect btw, me likey.
Logged

"No matter how many times I cut it.... it's STILL too short!!

Asian Icemen rise again...
http://www.soundclick.com/bands/default.cfm?bandID=903467
drolo
Posts: 346


David R. (Brussels)


WWW
Re: Presenting the Qi-Gon : Envelope Filter/ Envelope Controlled Auto-Wah/Tremolo
« Reply #3 on: January 18, 2013, 06:08:04 AM »

Quote
P.S. I did it on perfboard, YES, I am THAT crazy…

PHHHHHTTTTTTT!!!! Please... I'm doing an Infinitphase on vero.

http://www.diystompboxes.com/smfforum/index.php?topic=100664.0

You're a long way from crazy Mister.  icon_lol

Nice effect btw, me likey.

impressive !
i bow down unworthily ...

No pictures of the final build?
Logged

"The inventor of the bagpipes was inspired when he saw a man carrying an asthmatic pig under his arm. Alas, the manmade sound never equalled the purity of the sound achieved by the pig."
H i t c h c o c k

www.davidrolo.com
http://drolo.bandcamp.com
digi2t
Posts: 2514


Burning stuff, since 2009.


Re: Presenting the Qi-Gon : Envelope Filter/ Envelope Controlled Auto-Wah/Tremolo
« Reply #4 on: January 18, 2013, 08:35:29 AM »

Not finished yet. LED driver and power boards are done. Main board is missing some resistors. Still waiting on my enclosure as well. I`m starting to wire now. I`m hoping that it will be operational within the next week or two. Hen`s Tooth Cafe video will follow suit.
Logged

"No matter how many times I cut it.... it's STILL too short!!

Asian Icemen rise again...
http://www.soundclick.com/bands/default.cfm?bandID=903467
bluebunny
Posts: 1262


Marc B.


WWW
Re: Presenting the Qi-Gon : Envelope Filter/ Envelope Controlled Auto-Wah/Tremolo
« Reply #5 on: January 18, 2013, 09:05:02 AM »

This is the coolest thing I've seen today!  I have only one suggestion: please show us your layout!  I might have to build this...   Grin
Logged

[M][a][r][c]
Ohm's Law - much like Coles Law, but with less cabbage...
drolo
Posts: 346


David R. (Brussels)


WWW
Re: Presenting the Qi-Gon : Envelope Filter/ Envelope Controlled Auto-Wah/Tremolo
« Reply #6 on: January 18, 2013, 10:42:02 AM »

This is the coolest thing I've seen today!  I have only one suggestion: please show us your layout!  I might have to build this...   Grin

there ya go :-)

Logged

"The inventor of the bagpipes was inspired when he saw a man carrying an asthmatic pig under his arm. Alas, the manmade sound never equalled the purity of the sound achieved by the pig."
H i t c h c o c k

www.davidrolo.com
http://drolo.bandcamp.com
deadastronaut
Posts: 8766


Rob H. LONDON


WWW
Re: Presenting the Qi-Gon : Envelope Filter/ Envelope Controlled Auto-Wah/Tremolo
« Reply #7 on: January 18, 2013, 10:49:55 AM »

cool, love it.... Cool Cool Cool
Logged

moosapotamus
Posts: 1588


New Hampshire USA


WWW
Re: Presenting the Qi-Gon : Envelope Filter/ Envelope Controlled Auto-Wah/Tremolo
« Reply #8 on: January 18, 2013, 12:09:40 PM »

Nice! I love the combination of filter and tremolo. Sounds awesome! Cool

~ Charlie
Logged

moosapotamus.net
"I tend to like anything that I think sounds good."
StephenGiles
Posts: 5398


Re: Presenting the Qi-Gon : Envelope Filter/ Envelope Controlled Auto-Wah/Tremolo
« Reply #9 on: January 18, 2013, 03:12:12 PM »

This has an amazingly smooth sweep until it is swept right up to the high end, which impresses me greatly - now I was going to finish my tax return this weekend!!

Now might I suggest 2 parallel filters icon_biggrin
« Last Edit: January 18, 2013, 03:16:25 PM by StephenGiles » Logged

If you don't go when you do want to go, then when you do go you'll find that you've gone.
Mark Hammer
Posts: 21509


WWW
Re: Presenting the Qi-Gon : Envelope Filter/ Envelope Controlled Auto-Wah/Tremolo
« Reply #10 on: January 18, 2013, 07:32:26 PM »

The sounds starting around the 9:50 mark really show off what it is capable. of.

The Depth control's ability to differentiate between envelope influence on LFO and filter  is very nice.  The sweep control is also quite clever.  As for the Y-triggered filter, one of the worst-drawn schematics anywhere.  I know what the bidirectional sensitivity control does, but I'll be damned if I can point to the components that do it.  That said, I gather that all such bidirectional controls function by setting inverted versions of an envelope signal against each other.  Depending on which polarity "wins", and by how much, that sets the direction of sweep.

Because downward sweep is NEVER the exact opposite of upward sweep, when it comes to range, setting the starting point is critical, and I gather that's what you did in your choice of zener.

This is smart.  A little busy to be a stopbox  icon_lol but definitely smart.
Logged
alparent
Posts: 972

Alain (Gatineau Québec Canada)


Re: Presenting the Qi-Gon : Envelope Filter/ Envelope Controlled Auto-Wah/Tremolo
« Reply #11 on: January 18, 2013, 09:10:03 PM »

OK! I need to make a PCB of this. And that layout is just the inspiration I need.
This thing sounds amazing!
Logged

I'm french....If I make any mistakes....feel free to point them out!
jrod
Posts: 322


Re: Presenting the Qi-Gon : Envelope Filter/ Envelope Controlled Auto-Wah/Tremolo
« Reply #12 on: January 18, 2013, 09:18:27 PM »

Very cool! Love it!!!
Logged
Keppy
Posts: 693



WWW
Re: Presenting the Qi-Gon : Envelope Filter/ Envelope Controlled Auto-Wah/Tremolo
« Reply #13 on: January 18, 2013, 09:57:42 PM »

Nice work!
Logged
Ronan
Posts: 632

Ian


Re: Presenting the Qi-Gon : Envelope Filter/ Envelope Controlled Auto-Wah/Tremolo
« Reply #14 on: January 18, 2013, 10:45:20 PM »

Sounds very good, and has lots of control options to dial in what you want, very nice...
Logged
alparent
Posts: 972

Alain (Gatineau Québec Canada)


Re: Presenting the Qi-Gon : Envelope Filter/ Envelope Controlled Auto-Wah/Tremolo
« Reply #15 on: January 19, 2013, 07:09:25 AM »

Ok, I'm putting this schematic in Eagle so I can make my PCB.
A couple of things I don't get:
1. 2 brakes in the signal. One after the return jack and one after the SP3T switch
2. Where are all the LED and LDR on your layout?
Logged

I'm french....If I make any mistakes....feel free to point them out!
drolo
Posts: 346


David R. (Brussels)


WWW
Re: Presenting the Qi-Gon : Envelope Filter/ Envelope Controlled Auto-Wah/Tremolo
« Reply #16 on: January 19, 2013, 07:47:01 AM »

Ok, I'm putting this schematic in Eagle so I can make my PCB.
A couple of things I don't get:
1. 2 brakes in the signal. One after the return jack and one after the SP3T switch
2. Where are all the LED and LDR on your layout?

Yep, the layout was for personal use only initially. I did not think people would want to build this.
The brakes are where the signal gets routed on the bypass switch. I did not want to include the whole bypass switching but needed something to remind me where the ins and outs were :-)

For the LED/LDR i rolled my own from regular 5mm LEDS and Morley-Style LDRs.
The 2 for the filter are located right next to the 330k resistors north of IC1
The 1 for the LFO is located right under the 560k south from IC2.

Hope this helps.
Show me the results if you build it :-)
Logged

"The inventor of the bagpipes was inspired when he saw a man carrying an asthmatic pig under his arm. Alas, the manmade sound never equalled the purity of the sound achieved by the pig."
H i t c h c o c k

www.davidrolo.com
http://drolo.bandcamp.com
alparent
Posts: 972

Alain (Gatineau Québec Canada)


Re: Presenting the Qi-Gon : Envelope Filter/ Envelope Controlled Auto-Wah/Tremolo
« Reply #17 on: January 19, 2013, 12:05:10 PM »

I don't want to impose. But do to my low IQ I would really appreciate if you could put out a complete schematic.
And maybe some pics of the LDR/LED setup.
My special educator says that pictures or good for me! 
Logged

I'm french....If I make any mistakes....feel free to point them out!
mipo
Posts: 18


Re: Presenting the Qi-Gon : Envelope Filter/ Envelope Controlled Auto-Wah/Tremolo
« Reply #18 on: January 19, 2013, 10:11:16 PM »

I've never been interested in an EF/AW type pedal. . .   Undecided

I am now.   icon_biggrin
Logged
Mustachio
Posts: 627


Jim


Re: Presenting the Qi-Gon : Envelope Filter/ Envelope Controlled Auto-Wah/Tremolo
« Reply #19 on: January 19, 2013, 10:20:14 PM »

Sounds great! lots of cool sounds you got going on there!

Well done nice work  icon_wink
Logged

"Feed me or feed me to something, I just want to be part of the food chain"
Pages: [1] 2 Go Up Print 
« previous next »
Jump to: