Behringer - Hellbabe Wah

InTelejens · Post by **InTelejens** » 01 Mar 2011, 01:42

Hi, I just recently acquired one of these pedals and it makes a popping noise when the effect is engaged.

Anyone have any ideas on how to remedy this problem?

pinkjimiphoton · Post by **pinkjimiphoton** » 08 Nov 2011, 02:21

hey jIm,
any chance you have a schematic for the colorsound fuzzphaze?

JiM · Post by **JiM** » 08 Nov 2011, 21:13

pinkjimiphoton wrote:hey jIm,
any chance you have a schematic for the colorsound fuzzphaze?

Hmmm, nope. It was just a joke !

I guess that you may achieve something similar with your favorite tonebender followed by a Phasex http://analogguru.an.ohost.de/193/schem ... Phazex.gif

But if you find it, please report here !

pinkjimiphoton · Post by **pinkjimiphoton** » 09 Nov 2011, 01:35

i'm looking, JiM...if i find it, it'll be here!!!!!!!!!!!!!!!!

gotta couple other things i hope to contribute...

like a ps systems power tool...if i can get the fuggin' case open!!

demym · Post by **demym** » 09 Nov 2011, 19:44

Hi,

i have this wah too... in the past i had the Morley Steve Vai 1, but had to sell it for money... so,when i recently purchased the behringer, i really was looking for the sensor on/off behaviour similar to the Morley... you know, no switches to push, and very natural wahing when in the need

but... as you already know, even when this pedal is in off position, the sound is not the same as not having it at all in the chain.. i mean, i always hear such of a subtle little wahed sound even when in bypass position...

installing a tbp switch would be the obvious solution; but i'm asking myself, isn't there a way to make it true bypassable continuing to use the LDR sensor ??

Thanks in advance

JiM · Post by **JiM** » 09 Nov 2011, 20:56

demym wrote:installing a tbp switch would be the obvious solution; but i'm asking myself, isn't there a way to make it true bypassable continuing to use the LDR sensor ??

You may hack something with a relay instead of the JFET switches. The LDR and CMOS inverter stuff remains mostly the same.
You can get inspiration in the Behringer AB200 i've traced here

skylark44 · Post by **skylark44** » 23 Nov 2011, 01:57

varimac wrote:
nsn3 wrote:Hi there

Is there anyway to improve this pedal (swapping components mainly, the enclosure is pretty solid).

Thanks in advance

I acquired a Hellbabe very cheaply and came to the same conclusion as most others, ie:- too little travel.
After trying the 'rubber stop slicing' and the 'triangle extension', I found a tiny improvement but not enough to call the mod a success IMHO
After a few minutes watching how the pedal operated (with the baseplate removed) it became obvious that the pedal simply could not move any more - it needed to move beyond the limit of travel both forward and backward.
So using my trusty Dremel I sliced off angled strips from the front, back and sides. Take a look at the pics and you'll see what I mean. The Pic with 'Audio Fanzine' in the background is one I Googled of a standard Hellbabe. The othe pic is my modded HellBabe. You can see the much greater angle in the fully back position (this makes the biggest difference) - the angle in the toe-down position is also greater (but not quite so much).
Inside I lengthened the bigger aperture by about 3 - 4mm (so the pedal activates earlier) and lengthened the small triangle slot by a massive 4 - 6mm so the sweep feels about double the previous length.
Put it back together and Wow! Or should I say 'Wah!' Chalk and cheese! No comparison! Much, much more usable. Feels like a good, mid-quality wah now.

I only registered here to share this, so I hope it's of some interest/help to someone

Great idea Varimac, would it be possible for you to posr pics of your modded plastic/cardboard, so we could see exactly how different it is compared to the stock piece? Thanx!

skylark44 · Post by **skylark44** » 23 Nov 2011, 02:12

Does anyone know if it's possible to add a couple of Shottkey diodes...for a clipper, to the boost section (to make it more of an overdrive, instead of just a boost)? I think that would be way better than just a boost function (anybody else think the same?).

JiM · Post by **JiM** » 23 Nov 2011, 19:20

skylark44 wrote:Does anyone know if it's possible to add a couple of Shottkey diodes...for a clipper, to the boost section (to make it more of an overdrive, instead of just a boost)? I think that would be way better than just a boost function (anybody else think the same?).

I had the same idea, but i did not try yet.
Go on !

xfree · Post by **xfree** » 22 Jan 2012, 20:10

AndyPederson wrote:I have a Thomas 95-910511 cry baby and a Behringer HB01 Hellbabe wah.
I like both but prefer the sound of the cry baby.
I calculate that a mod (changing HB01 C19 to 5.6nF) would make them sound more similar.
My reasoning is as follows:

I set the HB01 to boost off, Q = cw, fine = cw, range = ccw
which I found to most closely mimic the cry baby.
I applied a 200 mv p-p sine wave and swept the frequency,
watched for resonance (max amplitude) on an oscilloscope,
measured frequency with a multimeter and measured amplitude with the scope.
With 200 mv p-p in I found the pedal up vs pedal down resonant outputs to be
820 mv @ 517 Hz to 1360 mv @ 2292 Hz for the cry baby and
800 mv @ 475 Hz to 1850 mv @ 1859 Hz for the HB01.
Note the lower pedal down resonant frequency on the HB01.

On the cry baby with the pedal down the wah pot is ccw and there is low resistance from wiper to ground,
and there is 100k from the wiper to the top of the pot.
On the HB01 this corresponds to low resistance of illuminated LDR2, and 100k at R9.
In either wah with the pedal down there is minimal negative feedback from the second transistor
(T3 on the HB01) and the resonant frequency is mainly determined by the inductor and the
capacitor in series with the inductor (L1 and C19 on the HB01).

The cry baby has a 510mH inductor and .01uF (10nF) capacitor.
In this thread the HB01 was said to have 900mH inductor, and C19 is 8.2nF.
The formula for resonant frequency is F = 1 / (2*pi*(sqrt(LC))).
For the cry baby with 510mH and .01uF (10nF) F calculates to 2230 Hz, which is close to what I measured.
For the HB01 with 900mH and 8.2nF F calculates to 1854 Hz which again is close to what I measured.
This also supports the 900mH inductor value for the HB01.

The HB01 has a lower pedal down resonant frequency because the LC product is higher.
The inductor value is 76% higher but the C19 value is only 18% lower.
To achieve a pedal down resonant frequency similar to the cry baby
the HB01 should have a .0056uF (5.6nF) at C19.
Then the HB01 resonant frequency calculates to 2243 Hz.

C19 is an 0603 surface mount capacitor (.06" x .03").
Changing this might be a more effective route than enlarging the cutout,
especially if you want to increase the resonant frequency to match a classic cry baby.
If LDR2 is already sufficiently lit to get minimum resistance then further enlarging cutout
will not further increase the pedal down resonant frequency.

The HB01 is said to be a clone of the Dunlop cry baby from hell, which I do not have.
My comments are geared to the Thomas 95-910511 cry baby which I do have.

Thanks to Jimmy for posting the Behringer wah schematic.
I found some spots that I think are not correct:
1: R16 (11k) in the boost circuit goes to pin 13 on the op amp, not pin 14.
2: R9 (10k) goes to +9V, not X8 pin 6; and X8 pin 6 goes directly to CD4069 pin 9.
3: The junction of LD2 cathode and LDR1 should be connected to ground.
4: The 470k resistor network R35 should have pins 5,6,7,8 tied to VB (+4.5V).
5: IC1 is the CD4069 and IC2 is the TL064.

I did this! It's great!
next is modding it to true bypass

skylark44 · Post by **skylark44** » 22 Jan 2012, 21:49

Cool, how does the Hellbabe sound now? (compared to before the mod) I'm all for improving it.

xfree · Post by **xfree** » 23 Jan 2012, 08:50

The frequency range now has more bite!

focusing on makin truebypass next

anybody knows how?

xfree · Post by **xfree** » 23 Jan 2012, 13:57

We know that the out/bypass loss a lot of tone

what I did to compensate I put a 100pf capacitor parallel to the output jack

try and let us know

xfree · Post by **xfree** » 27 Jan 2012, 14:25

demo of the hellbabe mod. courtesy of the article I've read here

skylark44 · Post by **skylark44** » 28 Jan 2012, 08:06

That sounded cool, I'll have to try the same mods on mine

...cool guitar riff, on the video too.

BigKen · Post by **BigKen** » 16 Feb 2012, 08:04

xfree wrote:The frequency range now has more bite!

focusing on makin truebypass next

anybody knows how?

What value cap did you use?

iluvchiclets · Post by **iluvchiclets** » 10 Apr 2012, 02:56

Could someone post a picture of the modified cut-out optical sensor opening?

I would rather get it right the first time, as opposed to making different cuts and using tape to repair them! I am having trouble imagining which sides need to be opened, or which direction the "trumpet" shaped cut is oriented.

A picture would be fantastic!

If one enlarges the optical opening, is that enough to increase the "wah" effect, or is it also recommended to lose the rubber feet/shave the pedal down at either end mod?

Thanks in advance!

skylark44 · Post by **skylark44** » 12 Apr 2012, 01:42

I did both mods to my Hellbabe (enlarging the triangle cutouts...and trimming the rubber stops), and it definately helped out with the wah effect. Just be slow...and very careful, when trimming the cutouts (I just scraped a little bit away at a time). I'm also swapping out the stock LED (with a clear/yellow, "Ultra bright" LED), for the optical sensor...to hopefully improve the wah effect further. Good luck with the mods, I'm sure you'll like the improvements.

iluvchiclets · Post by **iluvchiclets** » 12 Apr 2012, 18:44

Thanks for the reply, skylark44,

Ok, I understand that trimming the rubber feet will allow me to get more travel out of the pedal. I think I will do that as well.

In terms of cutting out the "triangle", which side am I enlargening or making longer? Do I:

- lengthen the beginning of the triangle (i.e., extend/lengthen the small end where the trumpet player puts his mouth);
- do I lengthen and widen the large end of the triangle (the area of the trumpet where the sound comes out);
- or am I increasing the area of the entire perimeter of the triangle?

I guess I could open it up and sit and watch it operate to figure out what to do - I just don't want to make a mistake.

And, BTW, mine doesn't sound too bad out of the box! If I can improve the smoothness of the wah effect it will be even better!

Thanks for reading!

iluvchiclets · Post by **iluvchiclets** » 12 Apr 2012, 20:30

Okay, I figured it out,

It was pretty simple to see once you opened the pedal up. The very small triangle is what controls the wah, and the small end of the triangle (where the mouth goes on a trumpet) is where the light begins to shine on the optical sensor. As the pedal travels, it moves along the trumpet until it ends on the large opening allowing the most light to shine through.

I could observe this effect with the pedal open, even with ambient room light exposed on the optical sensor. I could see that I needed to extend the small end of the triangle. I did not find it necessary to lengthen or enlarge the wide end of the triangle, as the maximum effect was already being obtained (as I noted by completely removing the light shield to obtain full LED brightness and maximum wah)

I did the cut very carefully and have made a difference by improving the point where the wah effect occured, and by making the effect a smoother transition. Before I did this "lengthening" of the opening, about 1/4 of the pedal's travel in the bass end did nothing. The finished cut is impossible to discern from the factory cut, as it was a marginal cut (approx 1 or 2mm)

I was surprised how good the Hellbabe sounded, even right out of the factory. Mine sounds very good - not at all like some of the demos I'd heard on Youtube. Perhaps it has been improved over the years? My date code is 0809.

Very pleased to read all about it on this forum!