Way Huge pcb...

Started by amz-fx, February 12, 2004, 06:58:14 PM

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aron

Try Duncan's tone stack simulator and your ears  :)

RDV

Hey, I never saw no 'tone switch' on the Swole Pickle!

Regards

RDV

WGTP

If I did the tone stack right, there is a big ass notch around 800Hz?
Stomping Out Sparks & Flames

bwanasonic

Quote from: RDVHey, I never saw no 'tone switch' on the Swole Pickle!

I was wondering about that. Just in fooling with values in the Duncan Tone Stack, it seemed like some sort of switch/ push-pull pot deal would be a good idea to switch the mid-notch in/out. Never saw any reference to the SP having a push-pull tone control.

Kerry M

Mark Hammer

One of the things about this forum is that it invites an extremely broad range of expertise and perspectives.  At one end we have actual cutting-edge designers, whose products we see in glossy full-page (sometimes two-page) full-colour ads.  At the other end we have kids who simply want a fuzz box for the fewest bucks so they can sound more like somebody they admire.  In between, of course, is a universe of levels of expertise and motives.

In some respects, one of the things that makes this forum different from something like, say, the amp forum at Ampage, is that the financial outlay for getting into building tube amps is pretty substantial, and the safety-related knowledge and theory necessarily high.  As a consequence the range of expertise there strikes me as being narrower, with more folks often having insight into the business and design aspects than they might here.  If I was 17, I could probably get into building myself pedals for the price of a couple of evening shifts at my crappy job.  I could probably not do that for tube amps.  This cost differential creates a kind of selective filter for the amp forums but no filter whatsoever for stompboxes.

That creates more noise than signal here sometimes (and a whole lot of repeating oneself), but at the same time the opportunity to bring light to those who are normally so far away from its source as to not know much about it is a truly delightful thing.

One of the value-added things about visits from folks like Ton, Jeorge, Zach, TomP and Howard Davis (come back, Howie! we miss ya) is a sense of how business and design and component manufacturers and consumer relations/feedback interact.  Much like a visit to your political representative's office and a day spent following them around can stop you from slipping into an X-Files mentality about how government works, speaking to people who depend on pedal design for their livelihood (as opposed to wanting their amp/guitar to sound like one they can't afford) does much to eradicate (or at least hold at bay) the kinds of naive beliefs many hold about the world of FX.

As I am fond of saying, wherever transparency does not go, fear, loathing, and paranoid conspiracy theories are more than happy to fill the void.

puretube

...Howie does visit HC`s FX-forum frequently these days...

SoundTech

Well, I don't get around here much, as other things in life have cut into my DIY time (all my projects are on the back burner, and the burner is set to "Barely any heat"), so I guess I get to chime in late.

*Mr. Huge: Thank you for this learning opportunity.  It was, well, very HUGE of you.


Quote from: Mark Hammer
It's a fuzzbox lads.  Get over it.
*Yeah, Mark, but as we all know, sometimes the journey is worth more than the destination.

*Mr. Coffee: Switch to decaf, man.  There's no need to start slamming someone who's trying to help people learn.

There's been a lot going on in my absence, and I gotta try to get back here more.  Thank you all for your wonderful contributions.
Sound Tech
  (((O)))

Joep

after 160+ replies still no partlist.....looks like I've drawn up the schem for nothing.... :(

Mr.Huge

"what kind of research did you do to end up with those values"
Honestly, I don’t remember. I’m sure I did a bunch of tweaking and listening, as well as trying to develop it with standard values.

"Hey, I never saw no 'tone switch' on the Swole Pickle!"
I added the switch because it sounds cool. I’ve done that mode on some custom pedals.

"after 160+ replies still no partlist.....looks like I've drawn up the schem for nothing.... "
Ask Jack.

"It's a fuzzbox lads. Get over it."
I agree!

-Mr. Huge[/quote]
BEN:   Mos Eisley Spaceport. You will never find a more wretched hive of scum and villainy. We must be cautious.

LUKE:   But I was going into Toshi Station to pick up some power converters...

VADER:   I find your lack of faith disturbing.

RDV

Quote from: Mr.Huge"Hey, I never saw no 'tone switch' on the Swole Pickle!"
I added the switch because it sounds cool. I’ve done that mode on some custom pedals.
Hey, what about instead of a switch, put a 100k pot wired as a variable resistor? Instant mid contour control! That is a very cool BMP tone control variation and I for one am thankful for the posting of it!

Thanks

RDV

Doug H

Quote from: Jason StoutI wish matched jfet arrays were made.....  :(

I hear ya! Especially if you could get them matched. I would have a lot of uses for that...

Doug

Doug H

Quote from: erix
Quote from: Jason StoutI wish matched jfet arrays were made.....  :(

Ask and you shall recieve!

http://www.linearsystems.com

ok,
erix

Oops! I should have kept reading! :D

Doug

Doug H

Quote from: aronTry Duncan's tone stack simulator and your ears  :)

Okay, I plugged in the original BMP values along with Jeorge's into TSC and came up with this:



The original BMP has a center freq around 1khz. The Pickle with .0033u has a center freq around 500-600hz with a much deeper scoop. I suspect this gives it a more "modern" sound with the deep scoop and (IMO) much more reasonable center freq. With the .01u switched in it has a shallower scoop, like the original BMP, but the center freq is down around 300hz. I suspect this gives it more of a "vintage" sound. My opinions come from looking at amp tone stacks and plugging them into TSC as well as my experience and ears.

I have found the stock BMP tone control to be fairly useless- too woofy on one extreme and too screechy on the other- just my opinion. It appears Jeorge did some nice tweaks to it to make it more useful and flexible.

I think the bottom line here is, if you are building a BMP circuit, tweak this tone control a -lot- until you are satisfied with it. Make sure it sounds good to you.

Jeorge has graciously provided his tweaks to this circuit, and I appreciate his contributions to this forum. Jack has already written about different ways to get different things out of this control too. Now it's up to you to take this info and tweak your gear for your own personal sound.

As a side note: I know I'm late to the party here, but just had to comment- Ebay prices are absolutely meaningless, aside from the collectors market.

Doug

rockstrongo

Hey, sorry to resurrect an old thread.....


I just had one quick question. I've plugged in all of my favorite Big Muff component values into this schematic, and I'm going to start working on it. The only question that I had was for a value that I could use for R2, the first component that the input hits, a resistor that goes to ground. I haven't seen this extra resistor on any other Big Muff schematics, so I'm not sure what I should try here.

Skreddy

That's what's called a "pulldown resistor."  It simply bleeds off any residual charge on the input cap so that when the effect is switched "on," it doesn't pop.  I generally see 1 Meg used here, but you could certainly go higher than that too.  Actually, if you just wire the bypass switch to short out the input going to the circuit when in bypass mode (I always wire my effects this way), you won't need a pulldown resistor.

puretube

I disagree: I do short the input @ bypass, but nevertheless discharge any given cap with a pulldown-R...

Skreddy

Out of habit?   :wink:

When off, wouldn't shorting it directly to ground discharge it plenty good?  When it's in use, it doesn't really need to be discharged, does it?

puretube

at the moment I break the contact to the input-jack, the outer "plate" of the cap is at a certain voltage (Vsignal in) - when I disrupt this, and discharge the cap to zero, there`ll happen a "voltage jump"...
if the output half of the footswitch isn`t faster than the input half,
that spike can appear at the output, in many cases amplified...

and, err, yes, ehh, out of habit... :?

cd

Quote from: SkreddyWhen off, wouldn't shorting it directly to ground discharge it plenty good?  When it's in use, it doesn't really need to be discharged, does it?

Yes, but the POP occurs when you turn the effect ON.  The input/output caps leak a bit of DC - when the effect is switched on, the voltage difference from the leakage and the caps charging up result in a pop.  The pulldown resistors send the leakage to ground so when you switch the effect on, there's no pop.

Skreddy

At the risk of sounding either stupid or like I'm trying to accuse you of being so, I must admit that didn't make any sense to me.  

If the cap's shorted to ground on one side (by the bypass switch) when it's off, and the input bias resistor (100k to ground in the case of the BMP) keeps the other side of the cap discharged... what DC leakage?  Sure; the cap charges up with the first input signal that's applied to it, but that's just the input signal; there's no residual charge hanging around anywhere.  And even if there was, how would a 1M to ground send that to ground instead of the input of the circuit?

And, Puretube, far be it from me to challenge your work habits.  Keep on doing what works for you.  And thanks for your cool freaking tube circuits.  What the hell are you working on right now?  You're getting ready to unleash something new on the world, aren't you?  I knew what it was a few months ago from your clues, but I forgot; sorry.  Another clue please?

Oh; and sorry about our election.  :oops: