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mr.adambeck · September 17, 2009, 08:47:01 PM

I want mine to sound like yours, RouseJeremy!!!!

mr.adambeck · September 17, 2009, 09:11:14 PM

Okay. Ummmn... WOW!

Adding the second knob turned this into my FAVORITE pedal I've built. I can dial it in just perfect to get the glitchy tone I was looking for.

YES!

rousejeremy · September 17, 2009, 09:52:14 PM

Thanks! If you fret very very lightly with a hammer on, you get a really cool lo fi fuzz sound without all the jumping around. That's what i was doing for the melody part. Then when you pick the notes at regular volume, all hell breaks loose. I showed it to a student and he was convinced the pedal was conjuring demons.

Quote from: mr.adambeck on September 17, 2009, 08:47:01 PM
I want mine to sound like yours, RouseJeremy!!!!

mr.adambeck · September 18, 2009, 12:47:08 AM

Anyone know any way to get more "gatedness" out of it? It makes a crazy screeching feedback a second after my notes when I'm not playing anything... If I could get it to stay gated it would be the perfect pedal for my new band...

mr.adambeck · September 18, 2009, 12:56:48 PM

I had an idea, but I have to wait until after work tonight to try it out. So, if the variable resistor (100k linear taper that I replaced the 100k resistor with) is raised to a higher value, would that allow me to get more gate out of it?

rousejeremy · September 18, 2009, 01:59:45 PM

I don't think it will. That resistor is a feedback resistor from one stage to another. Gating is caused by biasing.
I think it's pretty natural that it makes weird wooshing sounds between notes. Mine does and I read a comment from Doug Deeper who designed it stating the same.

Quote from: mr.adambeck on September 18, 2009, 12:56:48 PM
I had an idea, but I have to wait until after work tonight to try it out. So, if the variable resistor (100k linear taper that I replaced the 100k resistor with) is raised to a higher value, would that allow me to get more gate out of it?

mr.adambeck · September 18, 2009, 03:38:38 PM

Yeah, I found that if I adjust my playing style a bit I can control the feedback a little better. It's a pretty fun pedal! Completely insane at times, but very, very fun!

mr.adambeck · September 28, 2009, 05:53:52 PM

Anyone else find that this pedal is INCREDIBLY trebley? Anyone found a way to work this out? I'm thinking of putting something like this at the output, but I'm worried I'll lose too much gain (every time I put a tone control in anything I end up with the world's quietest pedal.)

mr.adambeck · September 28, 2009, 06:16:42 PM

Darn. Tried it, and I now have a 10db in volume drop from the bypassed volume. AAARRRGGGH!

Any help? Please?

Top Top · September 28, 2009, 07:09:58 PM

Quote from: mr.adambeck on September 18, 2009, 12:47:08 AM
Anyone know any way to get more "gatedness" out of it? It makes a crazy screeching feedback a second after my notes when I'm not playing anything... If I could get it to stay gated it would be the perfect pedal for my new band...

I had the same thing and had to experiment with transistors until I got the right combo. If I remember right, it was the last transistor that made the biggest difference in this, though the first one also had a big effect I believe.

Quote from: mr.adambeck on September 28, 2009, 05:53:52 PM
Anyone else find that this pedal is INCREDIBLY trebley? Anyone found a way to work this out? I'm thinking of putting something like this at the output, but I'm worried I'll lose too much gain (every time I put a tone control in anything I end up with the world's quietest pedal.)

Hmmm... mine is pretty unwieldy but I wouldn't say it is too trebley. However, there is a lot of volume coming out the back of this pedal... I think you could add a tone control and still be ok.

CynicalMan · September 28, 2009, 07:27:13 PM

Quote from: mr.adambeck on September 28, 2009, 05:53:52 PM
Anyone else find that this pedal is INCREDIBLY trebley? Anyone found a way to work this out? I'm thinking of putting something like this at the output, but I'm worried I'll lose too much gain (every time I put a tone control in anything I end up with the world's quietest pedal.)

Try playing around with the values. I would suggest using a low resistance and a high capacitance to minimize series impedance. Maybe a 1k resistor and .1u cap. Look here to calculate the cutoff:
www.muzique.com/schem/filter.htm

mr.adambeck · September 28, 2009, 08:01:24 PM

Thanks for the link! That's a really helpful calculator for me!

I ended up just throwing an LPB board that I had laying around in after it. Good to know that the resistor is what causes the volume drop though. Thanks!

mr.adambeck · September 28, 2009, 08:38:56 PM

Quote from: Top Top on September 28, 2009, 07:09:58 PM
Quote from: mr.adambeck on September 18, 2009, 12:47:08 AM
Anyone know any way to get more "gatedness" out of it? It makes a crazy screeching feedback a second after my notes when I'm not playing anything... If I could get it to stay gated it would be the perfect pedal for my new band...

I had the same thing and had to experiment with transistors until I got the right combo. If I remember right, it was the last transistor that made the biggest difference in this, though the first one also had a big effect I believe.

Can I ask what transistors you used? I followed the layout and can't figure out why mine seems so trebley and lacks as much gate as most peoples.

Top Top · September 29, 2009, 07:00:27 PM

Quote from: mr.adambeck on September 28, 2009, 08:38:56 PM
Quote from: Top Top on September 28, 2009, 07:09:58 PM

I had the same thing and had to experiment with transistors until I got the right combo. If I remember right, it was the last transistor that made the biggest difference in this, though the first one also had a big effect I believe.

Can I ask what transistors you used? I followed the layout and can't figure out why mine seems so trebley and lacks as much gate as most peoples.

I will check... I will have to open it up. I know I used a 2n2222 for transistor 2. I think I used 2N3904 or 2N5088 for the first and third ones, and maybe an mpsa13 for the last one? They were all just what I had laying around.

I think I tried the 5088s in the back and it seemed that it would gate immediately after you stopped playing, but the noise would come back after a few seconds.

Transistors 1 & 4 seemed to be the most crucial ones. On mine I had #2 hardwired in because I ran out of sockets when making it, so I didn't experiment with that one.

Dogue · October 03, 2009, 04:11:46 AM

I've tried to build this several times, using the schematic (and also the vero layouts as reference). Each time it sounds pretty good while playing, but it self-oscillates when not playing. I've triple-checked it, so I'm pretty sure I've wired up everything correctly. Any suggestions? A larger feedback resistor?

Top Top · October 03, 2009, 07:18:03 PM

Quote from: Dogue on October 03, 2009, 04:11:46 AM
I've tried to build this several times, using the schematic (and also the vero layouts as reference). Each time it sounds pretty good while playing, but it self-oscillates when not playing. I've triple-checked it, so I'm pretty sure I've wired up everything correctly. Any suggestions? A larger feedback resistor?

I don't know if a larger feedback resistor will do it. I put a pot in place of the feedback resistor, and turning it down doesn't increase the oscillation, it just makes it less controllable and less predictable when you do play through it.

I'd say Experiment with the transistors. I had to swap mine around a bit to get a good combo that sounded good yet didn't continuously make noise. Are you using exactly the transistors shown, or subs?

EDIT:

For those interested, I opened mine up to see what transistors I used:

1: MPS A42
2: 2N2222
3: 2N2222
4: 2N2222

I don't know anything about MPS A42 - It was just one I had laying around from a bunch of surplus electronics I bought a while ago. I swapped out a bunch and it was just the combo I liked the best.

I remember now that it was the last one I had to experiment with a lot to get it to gate properly, so try a 2n2222 or PN2222 if you've got one around.

ONE OTHER NOTE:

I don't actually know if the transistors I said were 2N2222 are actually that... they were in a radio shack package that was marked as that, but the transistors themselves are marked with numbers that don't yield anything when I search on them... They aren't typical transistor looking numbers though. My guess is that they are manufacturer numbers or something like that, and that they are indeed 2N2222 transistors.

Dogue · October 03, 2009, 08:44:55 PM

The transistors I used were as in the schematic: 2N4401, 2N2222, 2N3904, 2N3904. They were from Radio Shack in a package of fifteen containing five of each transistor (part 276-1617). I also tried different combinations but the circuits in the end all exhibited the same behavior. I'll try putting a 2N2222 at the end and report back.

Dogue · October 04, 2009, 01:37:01 AM

Well, I replaced the last 2N3904 with a 2N2222, and it works as expected now!

Top Top · October 04, 2009, 01:58:50 AM

Quote from: Dogue on October 04, 2009, 01:37:01 AM
Well, I replaced the last 2N3904 with a 2N2222, and it works as expected now!

Great, I am glad my info helped! (might be a first time

)

Dogue · October 04, 2009, 02:01:26 AM

Quote from: Top Top on October 04, 2009, 01:58:50 AM
Quote from: Dogue on October 04, 2009, 01:37:01 AM
Well, I replaced the last 2N3904 with a 2N2222, and it works as expected now!

Great, I am glad my info helped! (might be a first time )

Thanks. And since I built several copies, it would be especially nice if putting a 2N2222 at the end fixed them all...we'll see.

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