This ColorSound Wah that people rant and rave about, does that employ the inductorless wah schematic that I have seen floating around on the net? Anyone know anything about the ColorSound wah circuits?
All sussed out here:
http://diystompboxes.com/sboxforum/viewtopic.php?t=25279
I love the inductorless one myself. I think that's the most common one, the re-issues were inductorless.
Thanks! That answers my question. I'm going to build this one tonight and play around with it. Oh boy! :lol:
I have an swell fuzz supra wha colorsound and it have inductor. and use tropical fish and polypro box caps.
Quote from: cdAll sussed out here:
http://diystompboxes.com/sboxforum/viewtopic.php?t=25279
I love the inductorless one myself. I think that's the most common one, the re-issues were inductorless.
That is kick*ss! I HAVE to try that one. Thanks for the link. That was all talked about a year before I joined the forum so I never saw that post and didn't know there was such a thing as an inductorless wah.
cd, were the values NS gave you ever verified?
Quote from: Fret Wirecd, were the values NS gave you ever verified?
Yup. I checked it against a re-issue and the values were pretty much the same. I think the 5M7 was a 3M3 (to account for a different transistor) but other than that no significant difference.
I can't remember why I got rid of mine. Probably for $$$ to get other pedals, but I vaguely remember either the throw of the foot pedal was too large and the wah sweep too small, or the throw of the foot pedal was too small and the wah sweep was too large. If you're putting it in a Crybaby enclosure it may require some tweaking - easy with the single resistor Q adjustment.
Oh yeah if you look at the sweep on the second page of the thread I posted above, I *think* the sweep range (of the graph, not the actual Q of the wah) is 10hz to 10kHz, with the frequency scale (x axis) being logarithmic. I'll see if I can dig out my original simulation file but I'm pretty sure that's right since I do 99% of all my sims 10-10kHz.
Verified, that's great. :) Yeah, it does appear to have quite a sweep. I've never tried one, but I remember reading that the original had a long pedal throw. Probably best suited to the Vox shell then. Who knows, someone else might prefer it with the Crybaby's shorter throw. I wonder if the long throw was sore point, or part of it's charm as the "funky wah".
Almost forgot, I wonder if the Hotpotz, having a quicker taper than the "Icar types", might be help or hinderance to this ckt?
Well, I made up a little PCB (1-3/4"x1-5/8") and populated it tonight. In the morning I will test it out. Gotta go to bed now, I'm beat!
Paul, let us know how it sounds. :)
Quote from: Fret WireAlmost forgot, I wonder if the Hotpotz, having a quicker taper than the "Icar types", might be help or hinderance to this ckt?
IIRC the pot in the re-issue was linear taper :(
I wonder what the original pot taper was? That wah had enough of a unique sound where just cloning the original would be good. But, it looks like you could experiment a bit with short throw/long throw enclosures, plus quick (Hotpotz) and slower (Icar) pot tapers.
Tested it out this morning, seems to sound pretty cool. Woke up with an idea of how to make my own wah body and stuff, so I'm currently in the process of building it. I have created the base and footpaddle arrangement in the space of 2-1/2 hours. Now I just have to figure out how to make it all work. At least I have a wah to use as a guide.
Anyhow, I am curious about the pot, too. I have a Hot Potz from a CryBaby that I was using for testing. I'm not sure that the actual pot is really terribly important on this circuit, though, since it's a different animal from a inductor based wah. In this circuit, it's just a variable resistor, so it seems to me that the main question is: linear or log?
I'll post pictures of my creation in the next few days. 8)
FYI on the RI, the resistance goes from 36k (pulled up) to 0k (pushed down).
That's with the lin 100k?
OK, I have the basic wah assembly done. It took about half of my day today, but I am pretty happy with the results thus far. 8)
Check it out: http://www.diyguitarist.com/DIYStompboxes/DIY-Wah.htm
Addendum: BTW, does anyone know the taper on one of those 100K Hot Potz?
That has to be the most professional looking DIY wah shell I have ever seen.
Good work Paul.
Thanks nelson! :wink:
I'm working on the pot arrangement right now. With some luck, I'll have it wrapped up by tonight. I'll let y'all know when I'm done, and I'll update that webpage, too. 8)
Pretty sure it's a linear taper, I replaced the pot in my RI a few months back with a Bourns pot from wah-wah.co.uk
Well, I am 98% complete now. I just have to mount the bypass switch. :)
OK. one last question: Does anyone else experience a drop in volume with this circuit? The bypassed signal is considerably louder than the effected signal. BTW, I used a 2N5089 transistor. I am thinking that maybe it's due to my battery being down to slightly less than 8 volts. Any second opinions?
I don't remember any volume drop when I had my RI, nor when I breadboarded the circuit when testing out the circuit values (see old thread). A 2N5089 should have more than enough gain though. If not try increasing the collector resistor.
As for pot taper - my notes only show 0-36k, but again IIRC, the pot was going through a large portion of its rotation, more than 50%. If it was a linear pot, that wouldn't jive with the 36k range (36k in 100k linear pot is approx. 40% rotation). If it was a log pot, 36k would be over 50% of the pot rotation. However with the single variable resistor, you can play around with other resistors in parallel to get the taper you like, so log/linear shouldn't be a huge problem.
Interesting. In a Vox shell, I usually adjust a Hotpotz II to go from about 25ohm to about 95k, in other words, almost full value. That sounds odd, but when you chart out the taper in the Hotpotz, you see that it has a pretty fast taper, then it hits max value pretty early (around 1 o'clock), and holds that to 5 o'clock. Same with the Hotpotz I (120k).
Hmm, I'll try a new battery and see what results that yields. Maybe I'll have to mess with the collector resistor value. I just thought of something - I did use a 5.6M resistor, should that have been a 3.9M instead?
Here's a post from Harmony-Central from a guy who has the reissue. He's complaining about the volume drop when the pedal is engaged.
"The only drawback I found was a very SLIGHT volume loss when the effect is engaged. I have found that most (all that I've played) Crybaby's and Vox's have a short throw (bad for me) but a mid-range bump (good) that lets them cut through the mix. I wish the colorsound had a variable boost-that would be GREAT!"
Maybe we can make that happen for this poor soul...
:lol:
Shoot! Come to think of it, changing the collector resistor won't make a difference since the emitter is already grounded. And my transistor biasing theory is a bit hazy (OK, a lot hazy - what is this scheme called, collector feedback biasing?) but lowering the 5M9 resistor won't make any difference either. The key is the 330k input resistor - make that a 33k (and change the .01u cap to .1u) and the volume should be boosted up BIG time.
Also: for more volume without mucking around with the transistor, change that voltage divider on the output. Make the 47k resistor 100k.
Thanks for the suggestions cd.
EDIT: Had a thought. Won't changing the input resistor and cap change the frequency response of the circuit? I think I'd be more inclined to change that 47K resistor on the output to a 100K, and maybe use a trimpot.
Ummm... off the top of my head, provided you increase/decrease the cap/resistor in equal ratios (decrease one by 10x, increase the other by 10x, and vice versa) the frequency response should not change. But yeah, that divider on the output is the easiest place to start (DUH which is why I thought of it second, I never think of the easiest thing first :) ). There should be more than enough gain from the transistor, so you may find replacing the 100k/47k combo on the output with a 100k trimmer (or a 100k pot) acting as a volume control easier.
Again though changing that voltage divider will alter the frequency reponse (note the cap on the 100k resistor passing highs). If you lower the value of the 100k resistor, increase the cap value.
You know, while you're in there, I'd stick another transistor in there. Wire a 2nd transistor as an emitter follower buffer after the voltage divider (like the output of a TS-9). The output of the stock circuit is pretty high Z and can be loaded down like a regular inductor wah.
Quoteprovided you increase/decrease the cap/resistor in equal ratios (decrease one by 10x, increase the other by 10x, and vice versa) the frequency response should not change.
I was thinking that as I was driving back to work from my lunch break. Although this seems counterintuitive.
QuoteAgain though changing that voltage divider will alter the frequency reponse (note the cap on the 100k resistor passing highs). If you lower the value of the 100k resistor, increase the cap value.
I was thinking of changing just the 47K resistor to ground at the output to a 100K. By doing so, wouldn't that just increase the output level without changing the frequency response (at least by very much)? What I am really shooting for is at least unity. I guess I really need to try a new battery first! 8)
Just for the sake of recordkeeping, last night I changed that 47K resistor on the output to a 150K. That makes the effected signal just about as loud as it is when bypassed. I think with a brand new battery it will be perfect. I can't really say with 100% accuracy if the frequency response has shifted a little or not, but it doesn't appear to have, at least not noticeably.
I like the sound of this wah. It's a different animal than a CryBaby/Vox, though, in a good way. 8)
Very cool. Thanks for keeping us all updated on this, Paul. This one is going on my "to build" list. It looks simple enough for me at my level of experience.
Your'e welcome. :wink:
These twin-T wahs are kind of fun animals. I just had to build one when I learned that you could have an inductorless wah!
Yeah, me too. I didn't know you could have one without an inductor either. Hopefully I'll have some time to perf this one after I finish building and boxing my two projects (Marsha Valve and Sixteen Overdrive). Man, my setup is changing all the time now. :D
thats a nifty enclosure! Props on that beast; I may have to make a similar one myself... The idea i had was to use a belt sort of set up, kind of confusing... tie one one of a string to each end of the moving portion of the pedal, then tie to seperate holes in the pot shaft, so when it moves, one winds, the other unwinds.. don't know if it'd work in practice though.
PnL,
Jeff
You could try it the way the original Colorsound wah was done.
The method employed on the original Colorsound wah was clever - a fixed lever is attached to the foot paddle which goes up/down into the body. There is a black plastic slotted lever connected to the pot that pivots and slides along a pin in the foot paddle lever which turns the pot.
Here is a side view: http://www.diyguitarist.com/Images/ColorsoundWah2.jpg
I never thought I'd say this but this thing may have too much sweep! I'll see what the potential recipient thinks...But yeah tons more sweep than a crybaby, and mounted in a crybaby shell...This thing sounds pretty great!
Edit: on second thought, maybe my crybaby ain't quite right - in any case thumbs up on the CS....
Does anyone have a practical layout done for this schem that they wouldn't mind posting?? I am not great with making them , even with a simple and small crkt like this but probably could do with a bit of time. Just thought It would be easier to see one that someone else uses to give me a 'template ' to go by or use.
thanks
analog kid-
This is the PCB layout that I created when I built mine:
http://www.diyguitarist.com/PDF_Files/ColorsoundWahPCB.pdf
What would (most likely candidate at least) cause THIS circuit to act as a volume pedal rather than wah with the sweep??
I've built it twice now with two different layouts and both times all I get is a slight Volume effect!
I know with an inductor based wah that the electrolytic cap OR the inductor itself being bad can cause this but with a crkt like this one I just don't know how many things may cause this??
deviations from the schematic are:
a .0082 uf polystyrene cap in place of the .0062 uf called for.
and 150k/33k resistors in series in place of both 180k resistors.
Any ideas??
Paul - Thanks a lot for all the recent wah posts and especally for following up on Commonsound! I am going to perf it tomorrow thanks to your layout diagram. I have been interested in this one for a while because I have heard it has a huge sweep....I am also getting a red and yellow fasel for the moddable wah at over ggg.....so its going to be a wahnnderful weekend. :D :oops: Ya i know...that was bad.
I've got an old Frontline Wah that could do with a good pcb inside it so will give the Coloursound a go. Think I'll socket the output resistor and the jumper to give me the option of allowing for a Q control later
What's a good HFE for the trannie and which caps would I need to change to alter the frequency response? Im thinking of adding a rotary switch to do that ala the vox/crybaby mods.
Quote from: jmasciswannabePaul - Thanks a lot for all the recent wah posts and especally for following up on Commonsound! I am going to perf it tomorrow thanks to your layout diagram. I have been interested in this one for a while because I have heard it has a huge sweep....I am also getting a red and yellow fasel for the moddable wah at over ggg.....so its going to be a wahnnderful weekend. :D :oops: Ya i know...that was bad.
You're welcome. Hopefully you have better luck getting yours to work than analog kid. I know my layout works because I built my own from it. And, yes, it does have a large sweep.
Quote from: chrishopkinsI've got an old Frontline Wah that could do with a good pcb inside it so will give the Coloursound a go. Think I'll socket the output resistor and the jumper to give me the option of allowing for a Q control later
What's a good HFE for the trannie and which caps would I need to change to alter the frequency response? Im thinking of adding a rotary switch to do that ala the vox/crybaby mods.
I used a 2N5089 in mine. Hfe is somewhere around 600-700. On how to shift the frequency response, read the "Technology of Wah Pedals" at www.geofex.com - towards the end of the page.
Quote
I used a 2N5089 in mine. Hfe is somewhere around 600-700. On how to shift the frequency response, read the "Technology of Wah Pedals" at www.geofex.com - towards the end of the page.
Is this the circuit?
(http://www.geofex.com/Article_Folders/wahpedl/twinteewah.gif)
If I want to change the frequency response do I change the 0.1uF in the first T or the two 0.005uFs in the 2nd T? Sorry if I appear to be a complete noob about this (A Level in Electronics and do you think he can remember any of it???)
This brings a couple of questions to mind looking at that TwinT schem shown in RG's article.]
I was really concerned about which component values (especially the ones in the "T" of the crkt) had to be RIGHT ON for the crkt to work and which ones could be played around with a good bit and still have the effect.
The components in this one look almost nothing like the ones in the colorsound! Value wise. For instance I didn't have any 180k resistors for the T so I diddled with some series and parallels to get close. I thought this was keeping it from working. WELL there are 33k resistors in there on this one!!!! and the .0022uf and .0068uf caps in series at the bottom of the schem are replaced with two .005uf's . That makes me think (assuming these two designs are the most part the same)that two .0047uf 's could be used here. And I guess anything between 33k and 180k for the T resistors>?
SO are the values interchangable between the colorsound and RG's Twin T schematic ? or are there other things going on in each that makes the differing values WORK?]
ALSO : Why is there a second transistor in the schem on GEO?? Is it ONLY for adding that Volume control in there?
chrishopkins-
Yep, that's one example of a Twin-T circuit. I believe that you would have to change the resistor and cap values in both Ts to shift the frequency response. I don't really know for sure, though. I'm still trying to fully understand how this type of circuit works.
analog kid-
Yeah, the Colorsound circuit would probably work with a pair of 33K resistors and the .0068uF caps as well. I do think it's important that the values are reasonably close to the schematic in the Ts for it to work as intended. The actual values used will change the sweep characteristics and the frequency response. I think the second transistor shown on that schematic is to make up for losses in the filter section, or probably to provide some amount of boost when the effect is engaged.
I got one of those reissue big red enclosure type.
Yup no inductor in there and its gotta such a wide sweep- so it takes quite a bit gettting used to it !
It kinda of a pain at first but you will get the haNG of it.
Let me know if you wanna a pic of the guts or pcb . !! or any other info.
Quote from: goosoniqueI got one of those reissue big red enclosure type.
Yup no inductor in there and its gotta such a wide sweep- so it takes quite a bit gettting used to it !
It kinda of a pain at first but you will get the haNG of it.
Let me know if you wanna a pic of the guts or pcb . !! or any other info.
I would be interested to see all of the above. 8)
Here you go....
http://photos17.flickr.com/23260381_e3e9b53d7e_m.jpg
http://photos17.flickr.com/23260380_ee5970953e_m.jpg
http://photos19.flickr.com/23260379_d197361256_m.jpg
Sorry for the bad photos ....hope to get you better pics with another camera soon ok. The pot measures 120k one of those 'Bournes' with the left leed cut , mid to ground and the right leed to pcb all this looking from the bottom of pot ... and please ignore the 1/2 watt 2.2k resistor ...it's for the led.
The orange capacitors are 2x10k400 at each end and the middle one being 100k100 . The square one is 15nJ100 (0.015uF)... please stick to this value ... chaging it seems to kill the effect by distrupting the sweep range. Transistor BC1841. The 3 big silver radial caps are 4700 in the middle (big one) and 2200 for the smaller two.
Hope this helps.
buzz me if you any futher specific info.
Btw ... this is a nice wah... have fun building it !! :D
Talking abt the volume drop issue ... its not that a big deal coz when i used it playing loud ... really loud !!! straight after guitar and just before a nice hot dirt pedal - it was smokin. I gave up a Vox reissue for this.. just wanted some'in differant ... :roll:
If this does become an issue for all those building one, just buffer the input ... just a bit not too hot .... ! This circuit seems a bit sensative to me any tweaking seems to spoil it so thats why i have left it as is. !!
But please do go ahead and try what you guys feel would do best .... !! :lol:
Maybe a BC549 !!?? ala BOSS ! or maybe Mr Keens J201 for those who want it hot and fat !!
Hey Paul ... thats rocket science looking at your build .... to me you are an insperation. :wink:
goosonique-
Thanks for the pics. Not quite what I expected to see inside. Looks like a quality PCB and components. I wouldn't exactly call that first project of mine rocket science, but I guess it's a little complex. Have you seen my second DIY wah? It's quite a bit easier to fabricate...
http://www.diyguitarist.com/DIYStompboxes/DIY-Wah2.htm
No problems Paul .... btw i do have a nice piece of aluminium plate which always screams out wah-wah ... so hopefully soon after clearing my repair jobs might answer that calling. Hey nice build on your second wah.
see yas.. :D
goosonique-
Thanks. 8)
goosonique,
Are those axial lead silver caps on that board Polystyrene ??? Might also be a crucial element to the tone of this circuit along with just values , if so?
The one I built "works" but the sweep goes to an awful extreme bass end. I used a .0082 rather than .0068 uf cap and didn't think it would matter much , but I'm wondering if those cap values (.0022, .0068, and .015) might be the most important to be ALL dead on for this thing to have a usable pleasant sweep??First I thought it was the Twin resistors that needed to be Exact but I have them at 183k each now and there's no difference at all from 120-150k in those positions.
I also wish that someone would have that layout worked out as it is in yours ! I can ALMOST see it well enough to get the layout right but I would probably need a closer shot. I really like the long narrow PCB and the way the board is populated.
FYI the re-issue pics that goosonique posted look EXACTLY like the one I traced, so the schem I posted (see page one of thread) should match up.