Zvex - Distortron  [traced]

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Mich P
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Post by Mich P »

Any update on this one ?
Thanks !
Mich P.

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BrownMagic
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Post by BrownMagic »

Since this forum has taught me so much, and given me so many awesome effects, I just went out and bought a Distortron and cracked it open so that I could investigate the implementation of the Hi/Lo and Subs switches for you guys.

If you look at the AWESOME schematic of the box of rock in the other thread for reference...

-The High/Low switch shorts out the 330ohm resistor connected to the 3rd mosfet. I dunno if I can say this is verified, but I traced it to be this, and I run my continuity checker on the 330ohm resistor with the switch in both positions. When the switch was set to Hi, my meter told me that the 330ohm resistor was shorter. Good enough for me!




-The Subs switch is a spdt on-off-on switch.
The switch is connected to what WOULD be the 1uf coupling cap that connects gain stage 2 to gain stage 3, but this cap is cannot be 1uf any longer. I don't know the exact value. But in the center position (subs 1), it is just 1 coupling cap. Positions 2 and 3 each add in a different value capacitor in parallel to the coupling cap. Zvex says that position 3 is the stock BoR setting.

Using everything that we know, I'm going to assume that the coupling cap between stage 2 and 3 on the distortron is .47uf, and Subs 2 adds in a .22uF cap, and Subs 3 adds in a .47uf cap. I


I'm assuming this because .47uf in parallel with .47uf is close to 1uf, which is the stock box of rock coupling cap between gain stages 2 and 3. And adding in .22uf seems like a pretty decent halfway point.

I hope this clears up some of the confusion for you guys! Thanks again for everything!! :D

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Mich P
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Post by Mich P »

Many thanks BrownMagic .
Mich P.

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Mich P
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Post by Mich P »

Hi brownMagic
Pictures maybe ?
Mich P.

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BrownMagic
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Post by BrownMagic »

It really wouldn't be worth it. It's SMT, and I could barely see the traces myself. I'm positive my camera would fail at even picking up the resistor codes. But if you really want it just to see the build quality, I'll try.

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Mich P
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Post by Mich P »

Yes please, it just curiosity !!
Mich P.

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caspercody
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Post by caspercody »

Are you saying that the cap between stage 2, and 3 is 470n instead of the BOR value of 22n (looking at the BOR schematic)? Than the switch would in the first position be straight thru, second position add in parallel a 220n, and than in the third position add in parallel a 470n capacitor?

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BrownMagic
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Post by BrownMagic »

OMG! I messed up! Good call!

I meant between stage 3 and the Tonestack!!!! I will edit the post ASAP! Thanks caspercody!

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BrownMagic
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Post by BrownMagic »

BrownMagic wrote:Since this forum has taught me so much, and given me so many awesome effects, I just went out and bought a Distortron and cracked it open so that I could investigate the implementation of the Hi/Lo and Subs switches for you guys.

If you look at the AWESOME schematic of the box of rock in the other thread for reference...

-The High/Low switch shorts out the 330ohm resistor connected to the 3rd mosfet. I dunno if I can say this is verified, but I traced it to be this, and I run my continuity checker on the 330ohm resistor with the switch in both positions. When the switch was set to Hi, my meter told me that the 330ohm resistor was shorter. Good enough for me!




-The Subs switch is a spdt on-off-on switch.
The switch is connected to what WOULD be the 1uf coupling cap that connects gain stage 3 to the tonestack, but this cap is cannot be 1uf any longer. I don't know the exact value. But in the center position (subs 1), it is just 1 coupling cap. Positions 2 and 3 each add in a different value capacitor in parallel to the coupling cap. Zvex says that position 3 is the stock BoR setting.

Using everything that we know, I'm going to assume that the coupling cap between stage 3 and the tonestack on the distortron is .47uf, and Subs 2 adds in a .22uF cap, and Subs 3 adds in a .47uf cap. I


I'm assuming this because .47uf in parallel with .47uf is close to 1uf, which is the stock box of rock coupling cap between gain stages 2 and 3. And adding in .22uf seems like a pretty decent halfway point.

I hope this clears up some of the confusion for you guys! Thanks again for everything!! :D
NOTE: This is the edited and correct version of my initial post. Disregard that one.

Can anyone tell me how to edit posts? Heh...

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jfk1063
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Post by jfk1063 »

Hi,

Does this cap between gainstage 3 and the tonestack have to be a polarized cap (elco) or is MKT-cap ok?

Thanks!

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dune2k
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Post by dune2k »

Hi,
both are fine.

Cheers,
dune2k
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chris_d
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Post by chris_d »

Thanks for this BrownMagic!

I will have to open up my BOR build at some point and experiment with these. :thumbsup

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Post by jfk1063 »

dune2k wrote:Hi,
both are fine.

Cheers,
dune2k
Yeah thanks!

I allready tried it with the first filter cap, but then there is very little difference.

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BrownMagic
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Post by BrownMagic »

Anytime Chris!

And Mich, I can't get pics, sorry! Camera's being stupid. But yeah. Here's a link to the vexter box of rock http://www.beavisaudio.com/gg/images/zv ... vexter.jpg . It's similar to that, but SMT. The jacks are OK quality, not something I'd use in my own builds. The switch is cheaper too. But a decently solid pedal, and great sound for the money.

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steveb
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Post by steveb »

jfk1063 wrote:
dune2k wrote:Hi,
both are fine.

Cheers,
dune2k
Yeah thanks!

I allready tried it with the first filter cap, but then there is very little difference.
Please let us know the results. I'm curious to know if changing the 1uf cap to .47uf will decrease the low end. I just bought one, & would like to decrease the lows a bit.

Thanks,
Steve

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Post by jfk1063 »

Hi,
Just finished building a BOR/Distortron. Pics will follow.
It sounds great, but I don't hear any difference when using the sub-switch (between gainstage 3 and tonestack). I used a 0.47uf and then in parallel another 0.47 or a 0.22. Should the values be lower or is it something else?
Thanks

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Mich P
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Post by Mich P »

Hi, same problem here with this values
So i change for :
0.056uF parallel with 0,82uF = position 3 (BOR stock)
0.056uF parallel with 0,047uF = position 2
0,056uF alone = position 1.
It works better for me like this.
Mich P.

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BrownMagic
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Post by BrownMagic »

Like I said. I couldn't read the values at all, So I just guessed some values that made sense on paper. But if you got some good values Mich, I guess those are a great jumping off point for tweakers.

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culturejam
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Post by culturejam »

BrownMagic wrote:Like I said. I couldn't read the values at all, So I just guessed some values that made sense on paper. But if you got some good values Mich, I guess those are a great jumping off point for tweakers.
Most SMD resistors have a code printed on them that is for the value. Check out this page to "decode":
http://www.hobby-hour.com/electronics/4 ... istors.php

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BrownMagic
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Post by BrownMagic »

culturejam wrote:
BrownMagic wrote:Like I said. I couldn't read the values at all, So I just guessed some values that made sense on paper. But if you got some good values Mich, I guess those are a great jumping off point for tweakers.
Most SMD resistors have a code printed on them that is for the value. Check out this page to "decode":
http://www.hobby-hour.com/electronics/4 ... istors.php
Yeah, I used the resistor codes to verify that the distortron is the Box of Rock minus boost + switches. I'm very certain that I have the switching setups pegged correctly, but if someone disproves me, I'll commit effects hari kari. The values of the caps, I can't tell because they're not marked. And it's not possible to read with my DMM w/o desoldering them. In either case, you can mess with your own cap values. Why make a straight clone when you can do better? Heh

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