BLACK FOREST High Gain Preamp - Based on the Bogner Uberschall

[j2sip]

A newbie very late to the party..

Does the BOOGAZY layout contain/includes a clean channel? I'm very keen on a clean-crunch-more crunch pedal based on this very awesome design..

Thanks to JOK3RX!

Did I make a Boogazzy layout, I don't remember? Got a link?  

http://www.diystompboxes.com/smfforum/index.php?topic=98954.380

There you go, kind Sir. reply #386.. I'm kinda stoked by your enthusiasm about these pedals. And uh, i also want the new layout of the BF5, if I may.
Thanks!

[selfdestroyer]

J0K3RX,
DId Arzone make this layout available? I made your 1590B Triple Wreck and I would love to build this one also.

Cody

Yup! I gots it... Ya want it?

Perty Please. I am itching to start a build tonight.

Check yer email...   Anybody else wants it PM me.. not gonna post it here

I doctored it up a bit, not much... Just tried to make more clearance on some of the traces. Watch out for shorts!

Thanks so much, To the cave to etch!

Cody

[J0K3RX]

J0K3RX,
DId Arzone make this layout available? I made your 1590B Triple Wreck and I would love to build this one also.

Cody

Yup! I gots it... Ya want it?

Perty Please. I am itching to start a build tonight.

Hey man, if you build it hows about a sound demo? Also, I would like to hear the triple wreck if it wouldn't be too much of a problem? You don't even have to post it here if you don't want to, you can just send me a couple chuggin power chords or whatever... The same goes for anybody who builds the 1590b layout...please

[Maik]

Thanks JOK3RX 

[J0K3RX]

Trying the Black Forest with MOSFET... I think it will be the most brutal of all!....?  See any problems with it? 

https://dl.dropboxusercontent.com/u/11178619/BF_MOSFET/Black%20Forest%20Mosfet%20Basic%202.pdf

[duck_arse]

erm, those mosfets, they'd be wanting some positive bias voltage?

[J0K3RX]

erm, those mosfets, they'd be wanting some positive bias voltage?

Yes, and they do...

[duck_arse]

did you just add a line right the way across the bottom, or was I just not paying attention again?

yr last mosfet still no dc bias.

that first jfet wiring is frejking me out, now. what's the 50k pot control?

[stormbringer79]

Its a trimpot, to adjust the bias.

Jfets are not very reliable in manufacturing, hence the biasing by trimpot.

[J0K3RX]

Its a trimpot, to adjust the bias.

Jfets are not very reliable in manufacturing, hence the biasing by trimpot.

yup, what stormbringer79 said... I should have marked it "50k trim" and also it probably looks strange since I connected it using the "non conventional method" with pin 3 to ground.

[J0K3RX]

Still not satisfied with the straight Marshall type tone stack. It's alright but lacks independent frequency control and range. The sweep pot helps a lot but still not quite all there yet, if ya know what I mean...

I have been looking at this, seems like it could be set up to be very functional if you get the right frequencies... Anybody try/use this with any success?





Another more commonly seen approach...



Here are some various older Peavey stacks in a zip. I find these quite interesting! I believe James Brown from Amptweaker designed or co-designed most of these throughout his 18 years at Peavey ... Of course, he's better known for the 5150 amp design. He seems to know how to get "The Tone" being lead engineer with Eddie Van Halen on his amps for 13 years and worked with Joe Satriani to develop the original JSX amp... Pretty damn impressive resume' if you ask me! The man certainly knows his craft! I figure probably a good source to grab some ideas from...
https://dl.dropboxusercontent.com/u/11178619/Peavy_tone_controls/peavey%20tone%20controls.zip

[ggedamed]

Most of the graphic EQ pedals use the gyrator topology depicted in your first schematic (which is from R.G.'s site), although some use op amps instead of BJTs in the gyrators.
Even with standard EQ pedal frequencies, a graphic EQ will be miles ahead of the Marshall tone stack. If you're not sure if it would work for you, it's easy enough to fit an EQ pedal in the appropriate place.
BUT, since a long time ago, I'm carrying this in the back of my mind (from http://geofex.com/ - look for Simple, Easy Parametric and Graphic EQs at the bottom of the page):

Some recent commentary from Ed Rembold, Mark Hammer, and others has suggested that the ideal EQ for guitar use may be a hybrid of the graphic and parametric EQ's. Some players have contended that they need the greatest flexibility and adjustability between 700Hz and 1500Hz, not simply a couple of fixed bands, while they would prefer to have the bands of a graphic EQ bunched up a bit below these frequencies. Instead of a 60/120/240/500 Hz set of bands, perhaps only two or three bands at 80-100/200/400 Hz would be enough; a similar setup above the 700-1500 Hz range would allow adjusting treble. There is still some work going on in these areas.

As an aside, I'm experimenting with a LPF for controlling the treble, since I've never wanted more treble than the circuit is capable of providing. I have on my long overdue to-do list an EQ containing a variable HPF (bass), a variable LPF (treble) and 1-3 band parametric EQ for the mids. I even have the HPF+LPF part on a breadboard that I've not touched since the beginning of 2013 .

The last one is a variant of the James tone stack (the "passive Baxandall"). It has big signal loss, its controls interactivity is still significant and the bandwith per control is fairly wide, so it seems not a good match for extreme distortions.

[J0K3RX]

ggedamed - thanks for the input! I too was thinking of a HPF+LPF+parametric EQ type thing.. The best way for me to find out what will be a good choice will be to test and then test and then do some more tests... Been on my "things to do" list along with 1000 other things for quite some time. 

[GORENOISE]

hi all, i'm new in the forum and i been reading this post,.. Tomorrow i'm going to the shop to buy the parts but, what version of bf recommend?

[duck_arse]

well, now, which fets? for the mosfets, you can use 2N7000 or BS170, maybe VN10K. try all three! whichever you buy, get the datasheet and check yr pinouts! (and the last mosfet stage of the last posted version still needs some dc bias, to my eyes.)

as for the jfets, just about anything you can lay your hands on. J201 and 2N5457 are the most popular. they will both sound different. you can also try 2N5458, 2N5484 or 5, BF245A or B, 2N5952 or 3, 2SK30 and loads of other 2SK-types, many others.

some of those are backwards to the others, so you gotta get the datasheet to know for sure. good luck and welcome to the forum.

[verr76]

well, now, which fets? for the mosfets, you can use 2N7000 or BS170, maybe VN10K. try all three! whichever you buy, get the datasheet and check yr pinouts! (and the last mosfet stage of the last posted version still needs some dc bias, to my eyes.)

as for the jfets, just about anything you can lay your hands on. J201 and 2N5457 are the most popular. they will both sound different. you can also try 2N5458, 2N5484 or 5, BF245A or B, 2N5952 or 3, 2SK30 and loads of other 2SK-types, many others.

some of those are backwards to the others, so you gotta get the datasheet to know for sure. good luck and welcome to the forum.

Hi..
Farely new to the forum ... So much info all over the place that I most of the time find the right answer 

I'm giving the BF5 a try ... and I have 2SK30AY's at hand.. but the info about the pinout of these that I've found is moslty SGD, but also DGS.
here it says SGD:
http://www.diystompboxes.com/smfforum/index.php?topic=7497.0
and here DGS:
http://www.diystompboxes.com/smfforum/index.php?topic=54614.0
I've also read that "90% of the time" S and D are reversible.. I measured them with a DMM using this method (found it somewhere around here, just don't remember where):
" ------ 2. For JFETs: Drain and source conduct to each other both directions. Gate conducts to both drain and source one direction (junction forward biased) and not at all in the reverse direction (gate reverse biased). There is a 90% chance that drain and source are interchangeable. ------ "
My K30's read " K30AY  8B" .. Any way to know who the manufacturer is ?

Saludos from Mexico.

[duck_arse]

I would say hello in spanish, but I'd just spell it wrong and look a goose. hello, verr, and welcome.

if you go here:
http://www.datasheetcatalog.com/

they have a load of manufacturers trademarks showing. see if your fet has anything that matches. either way, get your datasheet for 2sk30, they should all be the same. I think it's gate centre, no? there is a thread hereabouts about the interchangeabillity of drain and source, you can search that.

for our purposes, sgd = dgs in this instance.

[candletears7]

Hi guys, I've got an etched board of the layout on page 1 of this thread.
Is this layout verified?
Any changes?
Keen to get into this.
And thanks for all the work on it! 

[Singulano]

Version 5 of Uberschall tested and highly aproved!
Live is much better than the video. And a little tip. The Voice Pot works better for me being 20KA.
Thanks a lot, J0K3RX!!

[Singulano]

https://www.youtube.com/watch?v=rM_3h6TnAOA&list=UUUwEIqPJirqqnKe85ggspRQ