freestompboxes.org

Bernardduur wrote:I think he used Tantalum caps for space as this caps were placed under a jack

I just used normal film caps and am very fond of my build; in a short while I need to A/B it with a friends original


Question; how would someone add a true stereo function on this pedal? I like it a lot but would love to use it in stereo with my (homebuild) Dumble and Trainwreck amps........ any ideas on this?

Ok, here's one of my first tries on schematics. Using the information from the site I listed in my first reply, I implemented stereo functioning! I honestly don't know how great my endeavors were. I would LOVE LOVE LOVE for someone to go over these and confirm and critique anything they want. I made changes based on those made by R. G. Keen on the site I listed. I wasn't sure what to do about the tremolo feed as Keen's stereo mods are for the original Univibe. Also, I swapped the 100k resistor and 0.1u cap around and added a 100k resistor for the second output mixer just where the dry signal from the preamp feeds into the "chorus/vibrato/tremolo" switch. This was to stay consistent with the original mods and original univox design, although I was simply guessing at what to do. The second output mixer was sort of a cut and paste, so it's a bit spread out and big for space. It's also a bit choppy. The univox did not have output buffers, so neither did the mods. I went ahead and treated the center wipers on the "output level" pot as the tips of the output jacks if there weren't buffers. Once again, I was simply guessing. Note that "ouput level" will have to be a concentric pot or two separate pots, if two are useful. The mode switch will need an extra pole. I made new lines in blue, and actual changes in.. magenta? Some sort of dark pink color to stand out. Please give me suggestions and feedback. Like I said, this is my first go with schematics. I've worked with diagrams for guitar guts, but not circuits. It was definitely fun, although I really just used the elements given to me. I'll see if I can get a pan function in here and a sweep control...

Nanoo

Not to get ahead of myself, but I had another question as well, which was addressed earlier to some extent. Instead of having different speed "ranges," couldn't you have just one single control for the whole range of speed? I read this today: http://www.geofex.com/circuits/ldrlfo.htm Can this be implemented? The next problem is how to get those extra waveforms without the standard design.

Nanoo

modman wrote:Roger Mayer's Voodoo Vibe - traced by Kaputepalla

Alessandro sent the files to me. Above 4 zipped pdfs:

VOODOOVIBE DELUXE LAYOUT.pdf 48K
VOODOOVIBE PCB LATO A.pdf 31K
VOODOOVIBE PCB LATO B.pdf 29K
VODOOVIBE LAYOUT CONNECTIONS.pdf 49K

Note that the little Voodoo Vibe is exactly the same circuit, on smaller pcbs. The original unit uses a double-sided pcb.

Alessandro in private mail to me wrote:This is by now a gift for you experienced dyer! I did't build this original version because i never make a double faces pcb! This costed me months of hard work but i think it's the king of cloned pedals! The components and the schematic are the same of the little voodoovibe (and now you'll know because mine is called 'little')

don't thank the messenger!
Noboby dare build this one without leaving us with a build report !

The link took me to some girly place ! Not that thats a bad thing but just thought you would like to know.

I finally finished it! I used the vactrols and it works fine. I wasn't sure if the 4.7k pots needed to be installed or not so I just used resistors 3.3k and 1.5k resistors. I don't plan on using an expression pedal for speed so I jumpered the two "x" pads. I rigged up a switch to do the RM, Univox and Bajaman cap values. I think I will most likely figure out which set I like best and leave them in. There is already enough controls on this thing and its a tight fit. Thanks Kaputepalla and KT66 and all who contributed for an awesome, great sounding project!

Does anyone know wich LDRs should be used?
Maybe these would fit:
light: 10k-27kOhm
dark: 1MOhm.

Those LDRs should work. The neat thing about this circuit is that it has that bias control in addition to the depth. You can tune in any decent LDR. I have ones in there that go down to 2k and up to 500k or so. This is in bright light in my shop, not sure what they go to in the circuit.

I just finished my build of this. I used a slightly modified layout of the one posted here to accommodate bourns style trimmers. It also properly deals with the unused opamp on one of the LM324's.

This thing sounds as good as my Univibe!

Thank you very much!
it works 100%, sounds fantastic!!
the caps switch is very useful
but it sucks out the battery rather fast

Well, I've been doing some interesting thinking on this project and how to make it stereo along with a pan effect with matching speed. Here's what I have come up with. All I will need to do is hook this effect up inside the same enclosure:

http://experimentalistsanonymous.com/di ... eo-box.gif
http://experimentalistsanonymous.com/di ... ox-pcb.gif

And I can do one or both of two things: Leave the speed/depth control of this pan effect out completely and hook the LEDs up to the same LED section in the VooDooVibe, matching the speed and depth of the vibe effect. OR, I could leave that section in there and put a switch in for an option between both speed controls. All you need is to switch the LEDs between the two circuits. Either way, I will also have a switch for a foot controller. I can't wait to really set up the complete design, but it will have to wait as I am procrastinating from a final exam as I type. The ultimate goal for me is to have a Pete Cornish type of setup with all my effects inside of one enclosure, so I don't mind all of the space I need. I do have a question for all of you who actually know about electronics, not just switching like me. Do I need to do anything to the output buffer on the VooDooVibe, or just leave it? I don't know how it matches up with the pan input. Pete Cornish actually uses an interesting technique in his rigs. I couldn't tell you what the actual circuit is, but in between each and every effect he has a preamp that acts like the input of an amp. It's really for impedance matching. The theory is that it makes the guitar act like it is plugged straight into an amp no matter how many effects there are in the chain. I don't know as much about all of that, but I would like to make sure these two effects will match up well feeding straight from one int other other. I assume it will be fine, but it's worth asking all of you here. Also, it doesn't matter that the two oscillators are wired differently as far as LEDs go since I'm just switching them out, right?

Jordan

soundclips?????

Alright friends. I have been pondering and pondering how to get this thing into a stereo version. Yes, I am crazy, and yes, it's complicated. My questions for those of you who know what you are doing:

How can I add an LED to the LFO that will operate twice as fast? How about 1/2 as fast?

The newer Voodoo Vibe + has a pulse function, and Beja mentioned very early on in the thread that our version does not have such a feature. How could it be added? It would make the tremolo effect more distinct. Would you need a different chip?

I can't really build this thing until I go ahead with modifications, so any help would be MUCH appreciated.

Jordan

I just ordered all the parts for this project, planning on building it next week. I decided to entirely copy the design of the enclosure, but I think I'll etch it this time. For anyone who's interested, I attached a PDF with the design. It's for etching, so just reverse the image if you want to use it as a standard decal. Illustrator (CS1) files can be supplied if needed. I'm gonna use a Hammond D, which is 188x120 mm.

Does anybody have a scaled .pdf of the transfer? I've been wasting a lot of ink and paper trying to find the proper scale on this one. Maybe it's easier with photoshop, but I don't have it.

I don't know if this thread is on anyone's radar, but I thought I'd throw this out there. I just assembled this circuit using the Vactrols rather than LED's and LDR's, as I think Greenskull commented, it just seems easier. Anyway, I plugged the circuit into a small Crate amp and am getting very low volume levels. The circuit seems to work, it's just REALLY quite. I have to turn the amp up to 10 to just get a very low volume level. With the circuit on my bench, I can hear local radio stations louder than the effect. Sometimes if I hit the strings rather hard, I get a brief, loud, distorted signal from it. Anybody have any ideas?

The buffer seems to work fine when I bypass the main part of the circuit. I don't think I will end up using that switching method though. I'd rather just wire it true-bypass.

Dr Jones wrote:I don't know if this thread is on anyone's radar, but I thought I'd throw this out there. I just assembled this circuit using the Vactrols rather than LED's and LDR's, as I think Greenskull commented, it just seems easier. Anyway, I plugged the circuit into a small Crate amp and am getting very low volume levels. The circuit seems to work, it's just REALLY quite. I have to turn the amp up to 10 to just get a very low volume level. With the circuit on my bench, I can hear local radio stations louder than the effect. Sometimes if I hit the strings rather hard, I get a brief, loud, distorted signal from it. Anybody have any ideas?

The buffer seems to work fine when I bypass the main part of the circuit. I don't think I will end up using that switching method though. I'd rather just wire it true-bypass.

Dr Jones,

I also built this pedal using vactrols, and trust me if you use the recommended yellow leds and LDR's it'll sound much better. I didn't think it would make a difference, but it did!!

goodluck

Frank

frankgb wrote:

Dr Jones wrote:I don't know if this thread is on anyone's radar, but I thought I'd throw this out there. I just assembled this circuit using the Vactrols rather than LED's and LDR's, as I think Greenskull commented, it just seems easier. Anyway, I plugged the circuit into a small Crate amp and am getting very low volume levels. The circuit seems to work, it's just REALLY quite. I have to turn the amp up to 10 to just get a very low volume level. With the circuit on my bench, I can hear local radio stations louder than the effect. Sometimes if I hit the strings rather hard, I get a brief, loud, distorted signal from it. Anybody have any ideas?

The buffer seems to work fine when I bypass the main part of the circuit. I don't think I will end up using that switching method though. I'd rather just wire it true-bypass.

Dr Jones,

I also built this pedal using vactrols, and trust me if you use the recommended yellow leds and LDR's it'll sound much better. I didn't think it would make a difference, but it did!!

goodluck

Frank

Hey Frank,

Do you remember which LDR's you used? I'd like to find something from Mouser. Earlier in this thread people posted that the type of LDR's used doesn't matter because the Bias control accounts for differences, but then others commented that the type of LDR does matter. That's one of the reasons I used vactrols. That, and I was too lazy to find a black tube to glue the LEDs and LDRs into. Thank you for the tip. I'll give the LEDs and LDRs a try. I wish I'd known this sooner - those vactrols weren't cheap.

As far as troubleshooting this circuit goes, I think I can use the circuits buffer as a sort of signal probe. I'm going to connect to the input cap of the buffer, plug into my cheap Crate amp, and poke around until I find the problem. I think I may have a transistor biased wrong. I probably put the wrong value of resistor in or something like that.

Thanks,

Dr Jones

Dr Jones,

I live in Australia, so just got what I could from my local suppliers, but they looked like the following from Small Bear : http://www.smallbearelec.com/Detail.bok?no=711

the 5mm ones.

I just placed the led and ldr as close as I could and used black heatshrink tubing.

regards

Frank

I started with this great proyect (thanks Alessandro, Baja and all contributing members), but have some doubts yet.

1) How to properly "close" the unused opamp?

As a voltage follower, with a voltage divider in the non-inverting input is correct?

2) How to properly eliminate the trimm pots?

Since I don't want to use that option, I save trimms and jacks for another work.
Both trimms are inserted in a voltage divider, so... I just can take the trimms off and left the voltage divider as it is, or I need to tame the resistors values?

Thanks for your help

1) How to properly "close" the unused opamp?

http://www.analog.com/static/imported-f ... op-amp.pdf

Thanks, jonasx26, I've seen that article before when I was looking for info so, I'll stay with this configuration 1) it's solved.

Now, what about the trimmpots? Anybody?

The first one I built, I just used four 2.2k resistors and put them in place of the trims, though there is probably an easier way to forget these altogether. I don't see a good reason for the expression control as it is limited to the speed setting's min and max. I am in the middle of building my second one this time with LEDs rather than the vactrols, based on the suggestion above. Frank, did you use the original cap values or bajaman's modded cap values?