Let's talk wahs

[Exactopposite]

There is a lot of info scattered about this forum about wahs, but I don't recall there bing a good wah thread for some time now. I have developed somewhat of a fascination when it comes to wahs, and having built/modded  a bunch of them I was hoping to start up a wah discussion here.

A few questions for the wah lovers among us:

Which pot do you prefer and why? Which inductor do you prefer and why? What transistors do you prefer and why?

The fulltone pot (and those "clyde" pots on ebay are identical) is the only pot that really does it for me as far as a current production pot. The hotpotz II has a spot in it where the change is too rapid, so the sweet spot is verry narrow. The so called icar taper pots sold at smallbear (and various other places) seem to have the sweet spot all bunched up at the toe down end. I recall reading something where G. Teese was saying that the fulltone pot was the only pot other than his that is a true Icar taper pot. I'll take his word for it. All i know is that the fulltone is the hands down winner in my book.

I'm a big fan of the whipple inductor. I like red/yellow fasel reissues also depending upon the particular wah. The whipple sounds more clear to me. i think the fasels can get a little muddy particularly in a wah that is voiced to have a darker or fatter sound already.

I pretty much always use bc108b transistors. I have tried bc547b's also and they sound pretty much identical to the 108's also. My #1 wah has a bc109c in q1 and a 108b in q2. Some people say they prefer bc109b's, but considering they have pretty much identical specs I'm not sure it makes a difference. I know i can get the 108b's from smallbear anytime, so that's what I've been sticking with. 

For anybody working on a colorsound, the bc109c just has too much gain for a colorsound. When I tried them in mine I would get feedback. Switching to 108b's fixed that for me.


I don't want to get into the whole "which _____  is the best" thing because it's all subjective and we have different goals for our sound, but I'd like to hear what you guys are using. Share your preferences with us.

[petemoore]

There is a lot of info scattered about this forum about wahs, but I don't recall there bing a good wah thread for some time now. I have developed somewhat of a fascination when it comes to wahs, and having built/modded  a bunch of them I was hoping to start up a wah discussion here.

A few questions for the wah lovers among us:

Which pot do you prefer and why?
  Quality...CB pot may be a lemon, nearly new with open. 
  And one I got for 15buxx [SB] has no opens, the V847 it's in needs GnoiZe fix.
  ...The pot that works well with the rest of the circuit.
  Which inductor do you prefer and why?
  R and Y Fasels, because they allow the dern wah to sound right [IMlimtedE].
  What transistors do you prefer and why?
  HG/LN [2n5088/MPSA18] for the boost position, BCxxx or any...that works well with the circuit for the other transistor.
The fulltone pot (and those "clyde" pots on ebay are identical) is the only pot that really does it for me as far as a current production pot.
  Well...you have better and more experience with the pots than I do.
  The hotpotz II has a spot in it where the change is too rapid, so the sweet spot is verry narrow.
  That's what my wah pots have.
  The so called icar taper pots sold at smallbear (and various other places) seem to have the sweet spot all bunched up at the toe down end.
  This one has no opens here...bunched up a little yupp...does sweep fine, a bit too coarse in the 'sweet zone' [mid/treble portion] to easily pick the %^&*wah setting.
  I recall reading something where G. Teese was saying that the fulltone pot was the only pot other than his that is a true Icar taper pot. I'll take his word for it.
  Wah pots...they get expensive...hard to pick out...they wear out...need to be 'fit' [may require circuit tweeks]..
  All i know is that the fulltone is the hands down winner in my book.
  At least your book has one, I have trouble with even full sentence without having doubts !
I'm a big fan of the whipple inductor. I like red/yellow fasel reissues also depending upon the particular wah.
  Since I'm not versed in the quality pot dept., whatever the fasel comments are should be heeded in a rather tempered fashion. The Fasels I found easy to work with and provided more 'WAH' instead of just 'whi' [as in whimpy, barely sweeping].
The whipple sounds more clear to me.
  i think the fasels can get a little muddy particularly in a wah that is voiced to have a darker or fatter sound already.
  It takes 'upgrade' components to make a better, more reliable, fine sounding wah.
  Tweekin' might not hurt. The "CB with R/Fasel" I bought is great, other than the pot. I bought, then tried out after take-back-no-tag-back period [1 month] had passed before I found the open spot in the pot.
  I pretty much always use bc108b transistors.
  +1 [...HG/LN in the boost position is nice].
  I'd say talk about the transistors as individuals since the jobs they perform are quite different.
  I have tried bc547b's also and they sound pretty much identical to the 108's also.
  BCxxx make a non-linearity that sounds like BCxxx to me, other than that the gian of course matters...
  My #1 wah has a bc109c in q1 and a 108b in q2.
  Close enough for me to to put a pretty solid ~1+ with that, the BC's, regarding gain but besides just have a tone to 'em the others don't. Not an end all...a different sound.
   Some people say they prefer bc109b's, but considering they have pretty much identical specs I'm not sure it makes a difference. I know i can get the 108b's from smallbear anytime, so that's what I've been sticking with. 
  IIRC the 109's are higher gain, nice feature for the boost tranny, high-ish gain seems to do 'it', MPSA18 for boost position Will be enough gain, I think slightly less gain transistors are or can be plenty too though.

For anybody working on a colorsound, the bc109c just has too much gain for a colorsound. When I tried them in mine I would get feedback. Switching to 108b's fixed that for me.
  This is a completely different circuit? no inductor ?
I don't want to get into the whole "which _____  is the best" thing because it's all subjective and we have different goals for our sound, but I'd like to hear what you guys are using. Share your preferences with us. .
  I think I maybe could be all or most of the way there with a decent pot in this CB with RF  wah...great sound, just has that little glitch in it.
  Potless...that'd be my preference, not having to change the pot would reduce the repairs...tweeking...expense...etc.
  I like the inductor wahs'...just certain ones, 'stock' whatever inductor wasn't going to do 'wah' I decided [after much tweekins]...Fasel opened the whi to become WAH.
  Other than that it's tweeking the shape and...that can be one thing wrong sets the whole thing 'off center'...finding the one tweek that lets all the other tweekin' get results can be hard to find.
  I messed and messed around, put pots/switches/sockets///tweeks on the 847...then tried out the CB, which at this point wins in reliability despite the pot which'd've been ok if it wasn't the victim of a manufacturing fault...which I didn't catch until it was perfectly new, out of the box, and out of warranty.

[shredgd]

In my (very little) experience, the yellow fasel was a big improvement over the stock inductor.
Regarding transistors, I once extensively tried some BC109s, but the tone just wasn't of my likings.. so I came back to the MPSA18.

[Exactopposite]

In my (very little) experience, the yellow fasel was a big improvement over the stock inductor.
Regarding transistors, I once extensively tried some BC109s, but the tone just wasn't of my likings.. so I came back to the MPSA18.

if they were bc109's without the  b or c suffix the gain may not have been high enough. the mpsa18's are VERY high gain transistors in comparison. Pardon me if you already know this, but a 109b means that the gain is in a certain range. A 109c is higher gain than a 109b (which would be higher than a 109a).

[.Mike]

I've been breadboarding wahs lately. I'm getting ready to build a wah that is actually two switchable wahs in one-- a Colorsound inductorless on one side and a typical inductor wah on the other.

I bought about four dozen new BC10x transistors from Newark (Multicomp brand). I tested them all in a Tech of the FF type tester, and here are the results.

Part #	# Tested	Low	High	Avg
BC109c	4	470	490	479
BC109	18	221	414	313
BC108c	2	464	486	475
BC108	12	178	208	194
BC107	11	152	167	157

Not a huge sample set, I know, so take the results with a grain of salt. Also, I kicked out one BC107 from my results that was more than 2x the gain of the next highest BC107 (358) and skewed the results.

Mike

[Exactopposite]

thanks for the info

[shredgd]

In my (very little) experience, the yellow fasel was a big improvement over the stock inductor.
Regarding transistors, I once extensively tried some BC109s, but the tone just wasn't of my likings.. so I came back to the MPSA18.

if they were bc109's without the  b or c suffix the gain may not have been high enough. the mpsa18's are VERY high gain transistors in comparison. Pardon me if you already know this, but a 109b means that the gain is in a certain range. A 109c is higher gain than a 109b (which would be higher than a 109a).

Yes, I know, sorry I didn't specify, they were BC109c's...

[Jered]

  Whipple inductor, no question about it.
   Pots, I like the old pots that Ohmite made for wahs
  Transistors depend on which wah board you are using.
  Depending on where your wah is in your signal chain, adding a buffer or boost to your wah can make quite a difference.  All the info is at GGG.

[Gila_Crisis]

while experimenting with transistors i found out that if you use in Q1 a transistor with a lower hfe than Q2 you get a better fat sounding wah!
on mine i have right now a BC107A in Q1 and a BC109C in Q2. the smaller the hfe in Q1 the better.
to me having high gain transistor in both Q1 and Q2 results in a weak sounding effect, you don't get all that vibe.
and i tryed a lot of then (BC550C, BC549B, BC107/108/109, BC239C, MPSA18, 2N3904, ...)

i also like a thing done in colorsound wahs: no resistor in parallel with the inductor and a jumper instead of the 1k res on Q2 collector. it sounds a lot more vocal!

btw i was thinking about changing the inductor (i still have the standard black cilinder in my vox), what are the differences between the red and yellow fasel? (i'm more for the yellow one, though)

[Jered]

what are the differences between the red and yellow fasel? (i'm more for the yellow one, though)

Not much, they both sound good. Don't overlook 2N4401 trans. They sound good. So do 2N2222A.

[Exactopposite]

while experimenting with transistors i found out that if you use in Q1 a transistor with a lower hfe than Q2 you get a better fat sounding wah!
on mine i have right now a BC107A in Q1 and a BC109C in Q2. the smaller the hfe in Q1 the better.
to me having high gain transistor in both Q1 and Q2 results in a weak sounding effect, you don't get all that vibe.
and i tryed a lot of then (BC550C, BC549B, BC107/108/109, BC239C, MPSA18, 2N3904, ...)

This is very interesting because I tend to do the opposite. I prefer to put a bc109c in q1 and a 108b in q2. I've done this in a couple of wahs and they both sound fatter than the ones that have bc108b's in q1 and q2. I've got some bc107a's around here though. I'll try one in q1 and see what happens. I'm not sure that q2 has much affect on the tone at all. I thik RG mentions this in the "technology of".

[Exactopposite]

what are the differences between the red and yellow fasel? (i'm more for the yellow one, though)

Not much, they both sound good. Don't overlook 2N4401 trans. They sound good. So do 2N2222A.

I would agree that the fasels sound very similar.

I'll have to try out a 2n222A also.  I've got some of those floating around here as well.

[Exactopposite]

what are the differences between the red and yellow fasel? (i'm more for the yellow one, though)

Not much, they both sound good. Don't overlook 2N4401 trans. They sound good. So do 2N2222A.

I would agree that the fasels sound very similar.

I'll have to try out a 2n222A also.  I've got some of those floating around here as well.

I replaced the bc108b in q1 of one of my wahs with a 2n2222a, but i really don't notice much (if any) of a difference.

[fNNR]

I've never built a wah but I'm just wondering, are inductors standard in wahs? If so, why? It seems kinda like some unnecessary hassle compared to using resistors and caps. Is it because the filter has a high Q which is hard to obtain (many components) with R and C? Or am I missing something?

[Exactopposite]

I've never built a wah but I'm just wondering, are inductors standard in wahs? If so, why? It seems kinda like some unnecessary hassle compared to using resistors and caps. Is it because the filter has a high Q which is hard to obtain (many components) with R and C? Or am I missing something?

all the answers are right here

http://www.geofex.com/Article_Folders/wahpedl/wahped.htm

[zombiwoof]

Regarding BC108 vs BC109, the BC 109 is supposed to be a low noise transistor and the BC108 is not.  The most important thing to consider IMO opinion is to get them in the 300-400 hfe range to get the vintage sound with the original circuit, your best bet to find those is with the BC109B (the "B" specifies a certain hfe range, "C" is hotter).  Other trannies will work if obtained in the same gain range.  The MPSA18's used in many new wahs are usually very high gain, and they make other circuit changes to make them work.

Al

[fNNR]

I've never built a wah but I'm just wondering, are inductors standard in wahs? If so, why? It seems kinda like some unnecessary hassle compared to using resistors and caps. Is it because the filter has a high Q which is hard to obtain (many components) with R and C? Or am I missing something?

all the answers are right here

http://www.geofex.com/Article_Folders/wahpedl/wahped.htm

Sweet, thanks.

[Exactopposite]

Regarding BC108 vs BC109, the BC 109 is supposed to be a low noise transistor and the BC108 is not.  The most important thing to consider IMO opinion is to get them in the 300-400 hfe range to get the vintage sound with the original circuit, your best bet to find those is with the BC109B (the "B" specifies a certain hfe range, "C" is hotter).  Other trannies will work if obtained in the same gain range.  The MPSA18's used in many new wahs are usually very high gain, and they make other circuit changes to make them work.

Al

Where would you purchase 109b's? I get the 108b's from smallbear but he doesn't have a 109b.

[.Mike]

Where would you purchase 109b's? I get the 108b's from smallbear but he doesn't have a 109b.

I bought mine from Newark. I'm not sure if they have the "mojo" of the Smallbear part, but they're half the price.

Here's a search to their BC10Xx transistors: http://www.newark.com/jsp/search/browse.jsp?N=500003+1001809&Ntk=gensearch_001&Ntt=bc10&Ntx=

If it doesn't work for some reason, you can search for BC10, then click Transistors, and then click Bipolar.

They have the full range for $0.31 - $0.34 apiece.



Mike

[Exactopposite]

thanks for the link