New boost/over-drive Project: The Vibin' Champ

[Torchy]

Im at work today but I'll post the layout tonight ...

[Torchy]

The unlabelled resistor next to C4 is the status LED series resistor, to suit whichever LED you use.
Anybody see any errors ?

[mojotron]

..
The unlabelled resistor next to C4 is the status LED series resistor, to suit whichever LED you use.
Anybody see any errors ?

That's great! Thanks.

Well here's the sound clips for the Vibin' Champ (VC):
Note 1: I used Torchy's sugestion and made R1=R3=3k and 2 J201s - Sounds the best to me - THANKS!!!

Note 2: Its really hot here today - (no AC and I do these in my attic  - 100+ degrees.. Yikes!) I did these clips quickly so I would not pass out - please excuse the roughness of the sound and playing...

Note 3: In the heat my S470 developed a buzz, so there is some buzz in the HB clips - it's my guitar/playing not the VC

Setup1: Ibanez S470 (w/Gibson Classic '57/'57+ pickups) -> VAMP (for small combo)->computer sound card

Clip 1: Clean Neck HB: VC set to Dr:30%, Tr:50%, B:50%, Vol:70% :I played using the neck HB pickup w/out the VC on for a D-G-D chord set then added it - so you hear the change when activated, then I played the same blues like stuff in all of these clips
http://www.mojotronics.com/images/vibinchamp/vc_4_clean_HB.mp3

Clip 2: Over-Drive Neck HB: VC set to Dr:70%, Tr:70%, B:60%, Vol:50% :I played using the neck HB pickup w/out the VC on for a D-G-D-am chord set then added it -
I play one lick, turn the vol back to 80% on the guitar, play just about the same lick, then turn it back up. The rest of the clip I try to show how the VC cleans up with pick attack when used as an overdrive
http://www.mojotronics.com/images/vibinchamp/vc_5_dirt_HB_N.mp3

Clip 3: Over-Drive Bridge HB: VC set to Dr:70%, Tr:70%, B:60%, Vol:50% :I played using the bridge HB pickup w/out the VC on for a D-G-D chord set then added it... This clip I try to show how the VC has a bit of grit - as an overdrive - I should have turned the bass up a bit...
http://www.mojotronics.com/images/vibinchamp/vc_6_HB_BR_dirt.mp3


Setup2: Warmoth (Swamp Ash) strat (w/Fender Fat '50's pickups) -> VAMP (for small combo)->computer sound card

Clip 4: Squeeky Clean Strat Neck: VC set to Dr:30%, Tr:50%, B:50%, Vol:70% :I played using the neck pickup w/out the VC on for a D-G-D chord set then added it - so you hear the change when activated, then I played the same blues like stuff in all of these clips. In this clip I switch the VC in and out 3 times (the VC level is a bit louder - so you can hear it kick in) in the first 1/2 of the clip, then I use the Guitar's vol control and picking attack to control dynamics in order to demo the sensitivity
http://www.mojotronics.com/images/vibinchamp/vc_7_clran._strat.mp3

Clip 5: Over-Drive Neck Strat: VC set to Dr:70%, Tr:70%, B:60%, Vol:50% :I played using the neck pickup w/out the VC on for a D-G-D chord set then added it - so you hear the change when activated, then I played the same blues like stuff in all of these clips. In this clip I switch the VC in and out a few times (the VC level is a bit louder - so you can hear it kick in) in the first 1/2 of the clip, then I use the Guitar's vol control and picking attack to control dynamics in order to demo the sensitivity
http://www.mojotronics.com/images/vibinchamp/vc_7_dirt._strat.mp3

You can here from this last clip that it does not have a lot of overdrive using vintage strat pickups - but with a FatBooster in front of the VC it sounds very much like a small Fender being over driven with a booster... I really like that sound myself.

Ok dudes, It's HOT - I'm out of here - I need to go to the beach!!

Thanks again everyone for the suggestions 

[newbie builder]

Great clips! Nice sounding little drive, as soon as I can get the parts together I think i'll build it. Great work!

[RedHouse]

Thanks for the suggestions, I made a few updates and reposted the files.

I did not intend for anyone to feel guilty, or for anyone to support something they did not want to...  I expressed this in a way that was inclined to be misunderstood - I think I have made it clearer now that this work is offered free without any obligation for any purpose - personal, commercial or other..... Have fun! There are a few more on the way.

I guess you just didn't get it.

It's great that you reiterate and edited the disclaimer...but... the religous slant in your disclaimer is still there, doesn't belong in this forum, please post your invitations of support for your favorite ministries in the Lounge forum, leave the schematics/layouts religion free is that asking too much?.

[tungngruv]

mojotron, thanks for the project, layout, soundclips and all your work. I was not bothered or offended at all.

[mojotron]

Thanks for the suggestions, I made a few updates and reposted the files.

I did not intend for anyone to feel guilty, or for anyone to support something they did not want to...  I expressed this in a way that was inclined to be misunderstood - I think I have made it clearer now that this work is offered free without any obligation for any purpose - personal, commercial or other..... Have fun! There are a few more on the way.

I guess you just didn't get it.

It's great that you reiterate and edited the disclaimer...but... the religous slant in your disclaimer is still there, doesn't belong in this forum, please post your invitations of support for your favorite ministries in the Lounge forum, leave the schematics/layouts religion free is that asking too much?.

Yes

[newbie builder]

RedHouse: I'm not religious, but I think he can put whatever he wants on his schem. I'm just glad that he is willing to share something he has worked on- lots of guys won't share stuff for fear of it getting ripped off (talked about in the naming thread) Just my .02

[Xavier]

Thanks Mojo for the project . Sounds like an interesting OD. I'll give it a try.

And, thanks also Torchy for the layout. Looks fairly easy to build.

I consider myself an atheist, but hey, mojo's contribution is great and we should show respect at the least, I don't have any problem with what he's trying to promote. Keep up the good job Mojo

[george]

Thanks for the suggestions, I made a few updates and reposted the files.

I did not intend for anyone to feel guilty, or for anyone to support something they did not want to...  I expressed this in a way that was inclined to be misunderstood - I think I have made it clearer now that this work is offered free without any obligation for any purpose - personal, commercial or other..... Have fun! There are a few more on the way.

I guess you just didn't get it.

It's great that you reiterate and edited the disclaimer...but... the religous slant in your disclaimer is still there, doesn't belong in this forum, please post your invitations of support for your favorite ministries in the Lounge forum, leave the schematics/layouts religion free is that asking too much?.

This is is the problem with a country that enshrines free speech in it's constitution - pesky people that insist on exercising their constitutional rights!

Maybe you'd feel more comfortable living in a country where such freedoms don't exist?

[Cliff Schecht]

Well seeing how he changed it without anybody asking, I must assume mojo is a reasonable man. I probably wouldn't have said anything if my day hadn't gone so bad. It's his right (and duty) as an American to express himself however he pleases. Censorship is a huge problem already in America.

[MartyMart]

Why can't we just "ignore" the religious slant and accept a very nice circuit, which has already been verified
and made into an easy vero layout, that we can all build and enjoy ?

I don't see any problem ( that's my own personal opinion )

It's like a "bad TV show"   .... if you dont like it ..... then DONT watch it !   why "complain about it"  ??

MM.

[Toney]

+1 Totally.
In Australia we call it whinging.

The man is dedicating his work to his beliefs and exercising his right to free speech whilst similtaneously NOT standing over anyone............so whats the problem? If your beliefs are different....just let it go.

Mate, that's a lovely contribution and I think 99.9% of the people here really appreciate your fine work.

[nelson]

Praise jebus, Allah akhbar, I am dedicating this post to Isis, thor and venus, the league against religious violence and Bob the satanist. They need a new spaceship to escape the madness. Also, please support your local athiests, they have the strength to face their eventual personal abyss.

[RedHouse]

Why can't we just "ignore" the religious slant and accept a very nice circuit, which has already been verified
and made into an easy vero layout, that we can all build and enjoy ?

I don't see any problem ( that's my own personal opinion )

It's like a "bad TV show"   .... if you dont like it ..... then DONT watch it !   why "complain about it"  ??

MM.

I wasn't meaning to "complain" about it, I was hoping we just wouldn't get started with religion in our stompbox forum, it's not the appropriate place. Having been hangin out here for about 5 years now I've been quite happy it (was) a non-political non-religous forum. Again, I'm a Christian too, don't have anything against that (obviously), and I'm all into American freedom (having been born here in the USA 47 years ago) it's just that there is a time and a place for everything, but I'll say no more of it so as not to cause any further waves..

Peace out.

[MartyMart]

No worries , I think this has ended well, with another cool circuit designed and ready to go

Peace ,
MM.

[QSQCaito]

nice soundings!, but ive got one tiniy question.. can it be used as a preamp/booster, just to boost signal, no distortion, clena sound


thanks

bye bye
DAC

[mojotron]

...
ive got one tiniy question.. can it be used as a preamp/booster, just to boost signal, no distortion, clena sound
...

Thanks.
Yes - IMHO, I think that this pedal is well suited as a preamp/booster if you want a Fendery sound - mostly becasue as an 'overdrive' it does not come close to the levels of gain you get from other devices that are called an 'overdrive'. What you hear on the clips is as much overdrive as it will muster by itself without putting a booster in front of it.

It does fendery clean sounds very well if you leave SW1 open - or if you don't use SW1 and use a 2n5457 for JN2.

[QSQCaito]

Very cool! Im going to build this one then.. its excellent to have a switch to select, i love that..

Which are the mods that made it sound better, r1+r3=3k..something else??

and.. regarding the j201, i can't find that one, have you got any replacement??

and.. last question,

what are the trimpots for??
thanks a lot

bye bye

DAC

[mojotron]

Very cool! Im going to build this one then.. its excellent to have a switch to select, i love that..

Ya - I like switches too - there is another mod where you can put a 1kB pot in series with Sw1 between the 2 V2 connections - this allows you to adjust the level of overdrive that kicks in - and if one makes Sw1 a stomp switch - that will allow for an adjustable "solo boost".... I'm not altogether crazy about an extra knob and stomp switch for this mod because the boost level is not that huge on this pedal - although it is very similar to the overall volume differenced with the 'boost' control on the Fulltone FD2.

Which are the mods that made it sound better, r1+r3=3k..something else??

Yes, use 3k resistors for R1 and R3. I will update the schematic to indicate this as soon as I can.

These resistor values are most important if you are using a JFET like the J201 - with a lot of gain. With the J113 and 2N5457 parts the values of R1/R3 did not seem to matter as long as they were  between 1-3k.

and.. regarding the j201, i can't find that one, have you got any replacement??

J201 JFETs are kind of unique in that they offer a lot of gain, low Vp (~.75v which I think aids a most natural breakup of the signal when being overdriven) and make a bit more of a darker sound - and they are relatively common. In my experiments 2N5457 parts sounded nice too - but the 2nd stage (JN1) sounds much better with a J201

and.. last question,

what are the trimpots for??
...

I got this info from the fetzer valve article at runoffgroove.com (this is a great read as it distills the work of Dimitri Danyuk, and others I believe, into a 'what you need to know format' - thought out and presented from the perspective of building a stomp-box circuit)

You really want your drain voltage (Vd) set to:

Vd = .6 * Vcc + .7 * |Vp|

Which for a J201 in this circuit this would be:

Vd = .6 * 9v + .7 * .75 = 5.925

It is common to see trim pots used on JFET circuits like this as most people want to try lots of different parts as each part offers it's own bit of 'mojo' - plus no one really wants to stop and measure Vp on all of their JFET parts... it's just a convenience and worth a $1 - or two - to me.