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My weener needs help

Started by octa805, December 13, 2012, 06:33:43 AM

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joegagan

Chordball, thanks.

A lower gain transistor for Q1 makes it easier to get an even response across the band and makes a more interesting texture to my ears.

One thing that spice modeling / real building back and forth ( i will often do a second round of tweaks in spice after the wah is built to further refine) is that we can make almost any part work, for example high gain trans , but when one part is changed it often requires five  or more other component changes to get back to a 'correct' frequency plot. Hence my reference to playing three games of chess at one time. I am currntly developing a wah that uses a joystick pot from sony playstation controller . The whole thing happens between 5k and10k on a 10k pot!

ch1naski

Your chess analogy perfectly describes my frustration.:)

Time to go to stock values and try some of your suggestions. As it stands now, I have very low output with the pedal heel-down. As I move to the toe-down position, the output increases, but it is a very clean sound, not unlike a tone control on a guitar. It actually resembles my Rosac NuWah more than my vox or Thomas.

Sent from my Nexus 7 using Tapatalk 2
one louder.

madbean

I've re-wired mine today to remove the Frequency pot. In its place I put a 2-pole 3 pos. rotary with the following values: 5n, 10n, and 20n. I also changed the emitter resistor of Q1 to 470R. I had a lower value in it before. 10n works well for me, but having the other options is nice.

Overall, I think it is an improvement and I'm going to stick with it. I think Joe is right with his observation of sticking in a lot of trimmers being the cause for less consistent builds. On the other hand, it's hard to predict exactly what features will work best for different ears....hence the feature creep that often comes into play in some of my projects :)

Anyway, mine currently has the output buffer hard-wired in, but I might add the switch in for it.

joegagan

Cool, brian, i thnik this good. Will the caps have 1 meg resistors to prevent popping while turning?
I have seen name brand wahs that do the switching without resistors, the popping is quite loud.

ch1naski

Quote from: madbean on January 13, 2013, 07:01:58 PMI've re-wired mine today to remove the Frequency pot. In its place I put a 2-pole 3 pos. rotary with the following values: 5n, 10n, and 20n. I also changed the emitter resistor of Q1 to 470R. I had a lower value in it before. 10n works well for me, but having the other options is nice.

Overall, I think it is an improvement and I'm going to stick with it. I think Joe is right with his observation of sticking in a lot of trimmers being the cause for less consistent builds. On the other hand, it's hard to predict exactly what features will work best for different ears....hence the feature creep that often comes into play in some of my projects :)

Anyway, mine currently has the output buffer hard-wired in, but I might add the switch in for it.
I am a victim of feature creep, myself.



"inductor mh and sweep cap are both doing pretty much the same job. once you get the gain dialed in, you can assess changes to the  overall freq curve using either mh or sweep cap changes.
you can move the mh up or down as much as 200mh with polepiece magnets in various configs applied to the sides or top or both. radical mh changes can occur when forcing two polepiece magnets into north/north config ( which they will not do unless taped or glued together)"

^^ this is something I've never heard before. Just strap on a couple magnets from an old pickup?

As for the freq pot, do I need to jump the pads on the board when removing it?
one louder.

madbean

#65
Quote from: joegagan on January 13, 2013, 07:33:35 PM
Cool, brian, i thnik this good. Will the caps have 1 meg resistors to prevent popping while turning?
I have seen name brand wahs that do the switching without resistors, the popping is quite loud.


I noticed the pop. Yeah, some resistors would be good here. I'll add those in tomorrow and report back. I'm really in overdrive mode here...trying to get all my gear together for a recording session next weekend!

It's easy enough to modify the existing layout for the three caps, but I'll consider re-tooling the layout in the future so this will involve less off-board wiring. Or, maybe a breakout board like the Fulltone one.

Here are some sweet small rotary switches I've started using, BTW:

http://www.mouser.com/Search/ProductDetail.aspx?R=SR1712F-0204-20F0A-N9-9virtualkey14860000virtualkey105-SR1712F-24NS

joegagan

Quote from: madbean on January 13, 2013, 11:38:58 PM
Quote from: joegagan on January 13, 2013, 07:33:35 PM
Cool, brian, i thnik this good. Will the caps have 1 meg resistors to prevent popping while turning?
I have seen name brand wahs that do the switching without resistors, the popping is quite loud.


I noticed the pop. Yeah, some resistors would be good here. I'll add those in tomorrow and report back. I'm really in overdrive mode here...trying to get all my gear together for a recording session next weekend!

It's easy enough to modify the existing layout for the three caps, but I'll consider re-tooling the layout in the future so this will involve less off-board wiring. Or, maybe a breakout board like the Fulltone one.

Here are some sweet small rotary switches I've started using, BTW:

http://www.mouser.com/Search/ProductDetail.aspx?R=SR1712F-0204-20F0A-N9-9virtualkey14860000virtualkey105-SR1712F-24NS

sounds cool brian.

those switches look good.

if people are interested in a more old style switch, i can send the following for 6$ each ( current similar grayhill part is over $12 ) it has 10 positions but you can find ways to put stops on the knob, or use all 10 positions!
6$ shipped in US.  if you buy more than 6, price goes down to 4.00 each, mailed in the US. note: 1/8"
shaft. 1/2" diameter, 5/8" deep including solder tabs. nut / washer included.


octa805

this thread sure evolved.

people love talking about my weener

I wish I could fix mine

ch1naski

still no love for your weener, huh?  i am gonna try going back to stock values, without freq pot, and start all over from there. I am pretty new to building stuff, so i may have to go over the values on the components again, just to rule that out. Since i've started building this thing, i've managed to build a silicon fuzzface, and a Ge Rangemaster from scratch on perf and vero, respctively, so i have a little more confidence / knowledge.

Plus, the wisdom of  these guys in this thread helping.  ;)

dont give up, man. we can do this.  I've already got two circuits in the "fail box" ( both of them octave devices....hmmm), but I will not put another board in there without a fight. especially a wah.
one louder.

octa805

Quote from: ch1naski on January 14, 2013, 04:41:14 AM
still no love for your weener, huh?  i am gonna try going back to stock values, without freq pot, and start all over from there. I am pretty new to building stuff, so i may have to go over the values on the components again, just to rule that out. Since i've started building this thing, i've managed to build a silicon fuzzface, and a Ge Rangemaster from scratch on perf and vero, respctively, so i have a little more confidence / knowledge.

Plus, the wisdom of  these guys in this thread helping.  ;)

dont give up, man. we can do this.  I've already got two circuits in the "fail box" ( both of them octave devices....hmmm), but I will not put another board in there without a fight. especially a wah.


Yea, it works but i want to love it and i dont yet.

I'm gonna build mine straight to jakefuzz specs. I love that sound. Trimpots are overkill for me

ch1naski

I was pretty close to those specs, but nothing like that sound. Hmmm

Please keep us posted on results. If I can get a good sound going, I can tweak it from there.

Why i started doing drugs and dropped out of college and electronics 101, I'll never figure out.  Sheez.....

Sent from my Nexus 7 using Tapatalk HD
one louder.

JakeFuzz

Quote from: octa805 on January 14, 2013, 05:10:35 AM
Yea, it works but i want to love it and i dont yet.

I'm gonna build mine straight to jakefuzz specs. I love that sound. Trimpots are overkill for me

Just let me know if you need some values or voltages. I have made a few minor changes I think since then but it should mostly be the same. I will be away on business for the next week but let me know and when I get back ill get you some data.

jkokura

Quote from: octa805 on January 14, 2013, 04:31:59 AM
this thread sure evolved.

people love talking about my weener

I wish I could fix mine

They say %40 of men...

Jacob
JMK Pedals - Custom Pedal Creations
JMK PCBs *New Website*
pedal company - youtube - facebook - Used Pedals

octa805

Quote from: JakeFuzz on January 14, 2013, 06:08:34 AM
Quote from: octa805 on January 14, 2013, 05:10:35 AM
Yea, it works but i want to love it and i dont yet.

I'm gonna build mine straight to jakefuzz specs. I love that sound. Trimpots are overkill for me

Just let me know if you need some values or voltages. I have made a few minor changes I think since then but it should mostly be the same. I will be away on business for the next week but let me know and when I get back ill get you some data.

sweet, thanks! I'm drowning at work as well so it will be a while on my end too.

ch1naski

So i've made some progress.

I was using a yellow Fasel and an inductor fro a JH-1 (whipple is in my Vox).
At first they were switchable. then for troubleshooting-sake, i removed the daughterboard and just installed the JH-1 inductor (the Fasel would'nt fir on the board with the bottom plate on).

no real wah, just more like a mild tone control and a lot of volume swell.

so after double checking trannie voltages and component values, solder koints, and wiring, i ripped out the inductor. it's a four-pin, but upon examination the  connection pins are caddy-corner from each other, not two-in-front with the two no-connection pins in back. Had to use a magnifying glass to actually see the wires.

turns out the fasel was bad, also. which is why it didnt work when i switched between them.
what are the odds?  :-[

so now i've got a whole lot of wah. i've got it mixed up in there with a jakefuzz suggestion on R5 (1k5), 150R on R4 (really dirty) and the freq pot disconnected.
Still seems to get a wear clicking sound with the buffer engaged, when i get near the heel-down position....gotta work on that.

just waiting to get back to the local electronics store to grab some various value caps (they have a lot of mojo-ish components in there, it's an old mom and pop style store) and i'll be rocking it out, right next to my rosac, vox, thomas, and 535q.

thanks for the help, everyone. I didnt mean to hijack the thread so much....


octa, now it's your time. let's get yours going, buddy.
one louder.