Zvex - Box of Rock  [traced]

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paparoni
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Post by paparoni »

mattpas wrote: Since this is somewhat based on the BSIAB I think if you remove one of the .002uf caps it should open it up more. If it is still too bassy remove the other one.
If this does work for you whatever cap you remove you can remove the 10k resistor with it and just jump it.
alright dude, i'll just try that for tomorrow, thanks a lot! :thumbsup

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Mr. G.
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Post by Mr. G. »

Since those are low pass filters, how would they decrease the bass if they were removed? or would it be more of a perceived decrease in bass, rather than an actual decrease?

I left the protection diode off my schematic, because I didn't feel like I needed it. I don't use anything that's not the normal negative ground boss style adapter. It might be a good idea for you to add it, though... simply for the extra protection.

As stated previously in this thread, it doesn't have to be the specified 1N5187. You can also use a 1N400x.

sliberty
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Post by sliberty »

Removing the caps outright might not be the best idea, especially in the case of the 2nd 22n cap (this cap is the only coupling cap in that position - it would change the circuit from capacitively coupled to to directly coupled if it was removed completely).

The Box Of Rock has two such 22n (.022uF) capacitors and a 1uF capacitor acting as coupling caps in the first three stages of the circuit. There is also a 100n cap (.1uF) leading into the 4th stage (if you built that stage).

I would think that the most likely candidate for a bass reduction mod here is the 1uF and also maybe the .1uF (if you have it). Cut these valuse at least in half (1uF -> .47uF or .22uF, and .1uF -> .047uF or .022uF), and see if that reduces the bass enough for you. You can always go farther if you like (.1uF and .01uF).

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Post by mattpas »

sliberty wrote:Removing the caps outright might not be the best idea, especially in the case of the 2nd 22n cap (this cap is the only coupling cap in that position - it would change the circuit from capacitively coupled to to directly coupled if it was removed completely).

The Box Of Rock has two such 22n (.022uF) capacitors and a 1uF capacitor acting as coupling caps in the first three stages of the circuit. There is also a 100n cap (.1uF) leading into the 4th stage (if you built that stage).

I would think that the most likely candidate for a bass reduction mod here is the 1uF and also maybe the .1uF (if you have it). Cut these valuse at least in half (1uF -> .47uF or .22uF, and .1uF -> .047uF or .022uF), and see if that reduces the bass enough for you. You can always go farther if you like (.1uF and .01uF).
If you change the .1uf off the tone control to a .01uf doesn't that give it a more scooped mids type of sound?

sliberty
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Post by sliberty »

Not sure which schematic you have, but the one I have doesn't have a .1uF cap near the tone control.

mattpas
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Post by mattpas »

sliberty wrote:Not sure which schematic you have, but the one I have doesn't have a .1uF cap near the tone control.
If you look at the first and second posts.
The first post schematic shows a 10n at the tone control but the second post states:

Hi friends
One mistake? with the Box Of Crock schematic
The 10n on the tone control should be 100n

sliberty
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Post by sliberty »

Now I remember. I was looking at a raw schematic file that didn't have the correction on it. Thanks for clearing that up.

madbean

Post by madbean »

New layout which includes dirt and boost sides. I have boards ready to ship. If you want one, please email me brian@madbeanpedals.com :block:

Image

Project Files (clickey):

Image

Image

PS looks like I have 10n on the tone control instead of 100n. I'll correct that in a bit.

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Post by SPeter »

Very good job! Thanks! :applause:

fusionid
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Post by fusionid »

quick question
I used a non polarized 1uf for C8. Will that change the tone much?
also as others have mentioned, original Madbean layout has tone lugs reversed :hmmm:

flügenheimer
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Post by flügenheimer »

Which components is used in the real pedal? the brands and so on. hope someone can help.

sliberty
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Post by sliberty »

Image

I got this board from Brian, and here it is populated. I can hardly wait to install in an enclosure, but not tonight. The board is excellent quality, and was a pleasure to work on. My only problem was down on the bottom where the three caps are positioned next to each other. My caps were higher voltage than needed (63V for most, and 100V for those big ones), and a a result, they are fatter and it made it hard to fit in the existing holes. I made it work though. And if you get 16V or 25V or even 63V caps, they should fit just fine.

Thanks Brian - really nice!

Steve

Russ
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Post by Russ »

After reading through this thread and viewing all the schematics and layouts, I'm still confused as to the CORRECT ACTUAL VERIFIED value of the cap across the tone control of the BOR. There's a lot of speculation, and everyone seems to have a different idea about it's value. Is it correctly supposed to be .1(100n) or .01(10n)? Has anyone verified this cap value without a doubt from an actual Box of Rock?
Thanks, Russ

madbean

Post by madbean »

I'm fairly certain that it has been determined to be 100n.

Russ
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Post by Russ »

Still, I'd love to have someone open an actual BOR and verify the 100n tone cap. This circuit is extremely bass heavy, and I wonder what that cap actually does (i.e. would a 10n cap cut some bass). I would swap it out and see, but I built mine very tightly on perfboard with the 100n cap, and it would be a royal pain to tear apart unless I just had to.

I notice that the new ZVEX Distortron pedal (the distortion side of the BOR) that's coming out soon has a 3-way switch to cut the bass, so the issue is obviously being addressed. I wonder what that switch is changing?

Russ

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Post by nooneknows »

Hi
Did you check the value of the .002 caps? in this thread there was someone who wrongly used a .022 instead of the correct .002, reporting the same amount of bass you notice.

Russ
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Post by Russ »

No, all my cap values are correct. I'd just like to know what that cap across the tone control does, and if IT'S the correct value.

Russ

Spewbag
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Post by Spewbag »

Thank you very much Mr Henry! Very helpful and clear instruction.

mrhenry wrote:spewbag,

for a handy guide to wiring up the board in the box with LED status light check out Beavis Audio or Gauss Markov's website.

http://www.beavisaudio.com/techpages/StompboxWiring/

http://gaussmarkov.net/wordpress/though ... p-a-1590b/


They are very clearly written; no need to scroll through multiple posts; the graphics are top notch. It's where I began learning stuff, and eventually, found this place.

-mrhenry

Caferacernoc
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Post by Caferacernoc »

markm wrote:Remember though,
According to Zachary, he does not use any ideas displayed on any of the DIY forums.
He has stated this afterall.
And yet each stage of the BOR is esentially the same as the first stage of the runoffgroove Peppermill.

Barcode
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Post by Barcode »

now now, let's be fair. true they look exactly the same minus 1 resistor value and replacing the source resistor with a pot, but to be fair that is just standard mosfet biasing, you will find that snippet in a million circuits. let's not get so granulated that we start getting down to the point where we start saying, "you know, both these circuits are using a .022uF input cap. CLONER!"

Not trying to defend ZVex, we all know he is a jerk. but let's make sure we pull reasonable evaluations of originality so we don't come off as even jerkier! :)

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