Sunking, everything works great, but I have a squeal with gain on zero!

Started by Cortexturizer, January 15, 2013, 10:53:34 AM

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Cortexturizer

I built mine last night, boxed it, and I must say it sounds GREAT. I was under the impression that the Klon is a fantastic booster and a tone tightener but that it has a medium to low quality overdrive. Not the case with my unit, at least to my ears, it sounds great, the sustain is wonderful, and the overdrive sound is pretty sweet I like it, kinda like a tube screamerish type of mid-boost but less compressed and with much more headroom, of course, this is with gain on half or more.
There is a lot of treble. Is this normal? I mean, I keep my Tone control on zero [all the way left] if I am using gain of 9 o clock or higher. If not, then I even might turn it up a bit [the treble], but still, a lot of treble, I don't know if this is normal?

I do have a slight problem with my build - usually people have problems with gain on max, I have a problem with gain on minimum! as soon as I turn the gain a tad up [like 3-5%] the scratching squeal stops.
So 100% clean, gives me problems, I can hear a squealing scratching noise it's kinda like a radio signal squeezed through a high-pass filter with added white noise on top. Marvelous...I wonder what I did wrong, I checked the wiring a hundred times, everything is okay. Maybe I have a faulty pot? [the pot is brand new]

I used the NE5532 for IC1/2 and ICL7660SCPA for the IC3.

Thanks!
https://kuatodesign.blogspot.com - thoughts on some pedals I made
https://soundcloud.com/kuato-design-stompboxes - sounds and jams

madbean

That is an unusual problem. Aside from re-checking your resistor and cap values, I would verify you are getting the VB voltage to the gain pot (follow the schematic to see which lugs it goes too). Maybe spray some contact cleaner in the pot, too.

As far as treble, most people raise that 3n9 tone cap a bit. I like 5n6 and some like 6n8. I do find it trebly otherwise through my Vox setup.

Cortexturizer

Thank you so much for the response.
I've read that some people get squeals and oscillations with the charge pump/NE5532 combo on a regular basis, I gotta try some TL072s in there asap.
It is an unusual problem, but I just can't seem to find the problem. Now this was far too late last night while I was troubleshooting and not sleeping obviously and getting my strength back for an early morning job, but I THINK, I THINK, I could hear a slight crackle while I was turning the Gain pot [similar to the SHO crackle but way less pronounced]. I am not sure, but I think I could hear that.
I'll check the resistor and cap values again, and as far as the wiring goes I consider this to be my magnum opus in that area haha, I really took my time. I will post pictures later.

As far as treble goes, I'm gonna record a clip when I get home, and I am sure that you will be surprised with the amount of treble on tap.
https://kuatodesign.blogspot.com - thoughts on some pedals I made
https://soundcloud.com/kuato-design-stompboxes - sounds and jams

midwayfair

Quote from: Cortexturizer on January 15, 2013, 10:53:34 AM
I used the NE5532 for IC1/2

There's your problem. Or at least one of them.

The 5532 will work "okay" in IC1, but it's not ideal. However, the 5532 has all sorts of problems in IC2, starting with biasing, white noise, inability to handle supply voltages above +15 ... Edit: This last one is important. Always check the datasheet before substituting. It's right there on the second page: 15V max.

Use a FET-based chip in both. The only real substitutions I'm aware of are some of the Burr Brown chips. Just use the TL072s.

Cortexturizer

Hm...okay. I was a moron not to check that out in the datasheet. Will try Tl072s and report back.

The craziest thing about this is that it sounds great, just trebly. And I mean GREAt. I get more gain than other people with clips of their clones on youtube. Fantastic sustain as well. I'll record a clip before the TL072 substitution and after and you will see what I mean.

I did use a burr brown chip on my Zendrive build, worked great and sounded amazing. I regret selling it to a friend. Of course, where I live, you cannot find a burr brown, so I will go with the TL072 and post back.

Thanks guys. You are the best.
https://kuatodesign.blogspot.com - thoughts on some pedals I made
https://soundcloud.com/kuato-design-stompboxes - sounds and jams

Cortexturizer

Hi guys!
I swapped the NE5532's with the aforementioned TL072's and everything worked as a charm, the squeal on the beginning of the Gain pot disappeared as is the excessive treble. Great. Pedal sounds even better now.

I immediately messaged the forum member Ward that had EXACTLY the same problem as I had, and today he told me that he got his going in full as well. Yay!

Here's a couple of pictures.















and a short demo of my uninspiring playing with a Strat [I'm mainly an SG player]

[soundcloud]https://soundcloud.com/earthless/lots-of-gain-with-centaur[/soundcloud]

Long live DIY!
https://kuatodesign.blogspot.com - thoughts on some pedals I made
https://soundcloud.com/kuato-design-stompboxes - sounds and jams

madbean


pickdropper

That looks really cool.  For some reason, the straight lines remind me of Tron.
Function f(x)
Follow me on Instagram as pickdropper

Cortexturizer

Thnx people, much appreciated!
If you're wondering what Kuato is all about, you may remember him as a baby coming out of that guy's stomach in Total Recall haha. Open your miiiiiiiiind!

:D
https://kuatodesign.blogspot.com - thoughts on some pedals I made
https://soundcloud.com/kuato-design-stompboxes - sounds and jams

Liustucru

This is a how-to-wire-perfectly-your-pedal lesson !!!!!!!!!!!!!!!!

midwayfair

Wow, that's clean inside. Excellent graphic (is that gold ink?!) and knobbage.

(Nice playing on the clip, too!)

Cortexturizer

Thank you guys for the kind words.
Yeah, I really took the time to wire this nicely. I enjoy wiring a lot, and populating the board. I love designing the finish, but HATE doing the finish! It's because I never found a way to do it and be absolutely satisfied, while keeping the process relatively simple [you cannot buy waterslide decals in my country, yep, living in a cave...]
As for the graphics, I did the design, and what that essentially is, is a gold self-gluing glossy paper, really thick, and on top of that I did a transparent dark blue folie that covered the gold paper in certain areas but not all of them. On top of that I poured some epoxy resin, like this



While it does look great, I wouldn't recommend it for professional purposes [i.e. you're building for sale], I mean, I like the little amount of sloppiness [it enforces the DIY spirit] but some of you may not.

Really a great sounding effect.

Cheers good people!
https://kuatodesign.blogspot.com - thoughts on some pedals I made
https://soundcloud.com/kuato-design-stompboxes - sounds and jams

pickdropper

Quote from: Cortexturizer on January 16, 2013, 01:35:46 PM
Thnx people, much appreciated!
If you're wondering what Kuato is all about, you may remember him as a baby coming out of that guy's stomach in Total Recall haha. Open your miiiiiiiiind!

:D

Quaaaaaaaade.  Turn the machine on......
Function f(x)
Follow me on Instagram as pickdropper

Ward

Quote from: Cortexturizer on January 16, 2013, 01:21:14 PM

I immediately messaged the forum member Ward that had EXACTLY the same problem as I had, and today he told me that he got his going in full as well. Yay!

Yes indeed, thanks again Cort, it has been a year and a half since I threw the pedal in a box and wrote it off as something I would never fix. I had the wrong charge pump apparently but even after finally ( 3rd time lucky ) acquiring the correct chip the problem was still there. For some reason which I have no memory of why, I had put one NE chip in there along with one TL072, no idea why I did that but after I swapped it out the thing works right now. Who'd av thunk it.
You want HOW MUCH to fix it.

Cortexturizer

https://kuatodesign.blogspot.com - thoughts on some pedals I made
https://soundcloud.com/kuato-design-stompboxes - sounds and jams