Another New Design.. i present you the "DUI distortion"

[dschwartz]

Hello world!!
i´m so happy to present to you my new baby.. the DUI Distortion!


I called it DUI as Driving Under the Influence, cause it sounds like my mayor influences (satch, van Halen, SRV), and at the same time, it has design influences that jump to the eyes..

It has a little of BSIAB, a little tubescreamer (not so much) AMZ BMP tone control..

How It sounds??
Well, i was blown away when i tried this configuration, i tried for days and days different gain stages and values, i started to hear that u-amp clipping wasn´t really nice, so i lowered the gain of those, and the input section is a blasted tubescreamer-like overdrive, with leds for a harder clipping, and a lot of more gain..

The sounds, i would define it as NO FUZZ ALLOWED!..the sound is very soft, touch sensitive, dynamic, with a lot of bite and sparkle. For me, it gives the perfect brown sound.. very transparent, you can hear the guitar through the distortion, but very overdriven and compressed..van halen fans..this is it!...

With a strat and the gain at half or less, it gives very texas blues sounds..overall, it sounds very tubey to me..

gain control is very effective it goes from full clean, to some compression, to blues grit to heavy overdriven..i just love it..

i´ll post a soundclip asap.. i invite you to breadboard/build it and enjoy!

[Arn C.]

Looks great!   So, you used leds ,  what kind?  Red? 5mm or 3mm?
Really want to give this a go, sounds like a great pedal!

Peace!
Arn C.

[dschwartz]

i used 5mm leds..i don´t think there´s too much difference with 3mm leds..

[Ice-9]

Hi, Congrats that looks like a nice circuit to breadboard, I like the op amp front end as it would seem as the one big drawback of the gain section on the bsiab2 is that it doesn't change the amount of drive it just alters the level of the drive into the second stage. With you op amp design you can back the gain off to a cleaner signal to drive the rest of the fet stages. I hope i am explaining myself correctly. thanks for the diagram.

[Arn C.]

Thanks Daniel !    Red ones?

Peace!
Arn C.

[ayayay!]

Thanks Daniel !    Red ones?

Yeah what type of LED?  Water clear vs. diffused can make a huge difference.

This looks really cool and not too difficult!!!  I'll have to try it.  Thanks for your continuing contributions dschwartz!!!!  Wow, 4 J201s... Interesting

You might label the Gain pot on the schem.   

[dschwartz]

Hi, Congrats that looks like a nice circuit to breadboard, I like the op amp front end as it would seem as the one big drawback of the gain section on the bsiab2 is that it doesn't change the amount of drive it just alters the level of the drive into the second stage. With you op amp design you can back the gain off to a cleaner signal to drive the rest of the fet stages. I hope i am explaining myself correctly. thanks for the diagram.

exactly, that´s what i wanted the gain control to do..at zero, the sound is clean-clean..a little dull, but clean, when you increase the gain, you add treble and harmonics, and the signal starts to compress..u-amps do that job very well..i found the gain control a lot like tube amps gain..

[dschwartz]

Thanks Daniel !    Red ones?

Yeah what type of LED?  Water clear vs. diffused can make a huge difference.

This looks really cool and not too difficult!!!  I'll have to try it.  Thanks for your continuing contributions dschwartz!!!!  Wow, 4 J201s... Interesting

You might label the Gain pot on the schem.   

i forgot to label that..but hey..there are 4 pots, and 3 are labeled..a little logic, and anyone can see which is the gain pot..

about the leds...there´s no critical part here, use any led you have and chose the one one you like most.. i used red 5mm clear leds, the typical, just cause they where handy...

for the opamp, you can use a 741, or a 4558, or any opamp, i used tl082..

i think the only part is not easily changeable are the fets.. i´m quite sure j201´s are big part of the sound ..you can change the upper fets, since they only work as current sources, and they dont amplify..

one thing i love about it is the lack of trimpots..

[Arn C.]

Thanks!!!!!!!!!!


Arn C.

[ayayay!]

one thing i love about it is the lack of trimpots..

I noticed that.  Very cool.  I'll have to try this guy out. 

[Ice-9]

Hi, Congrats that looks like a nice circuit to breadboard, I like the op amp front end as it would seem as the one big drawback of the gain section on the bsiab2 is that it doesn't change the amount of drive it just alters the level of the drive into the second stage. With you op amp design you can back the gain off to a cleaner signal to drive the rest of the fet stages. I hope i am explaining myself correctly. thanks for the diagram.

exactly, that's what i wanted the gain control to do..at zero, the sound is clean-clean..a little dull, but clean, when you increase the gain, you add treble and harmonics, and the signal starts to compress..u-amps do that job very well..i found the gain control a lot like tube amps gain..

Thats exactly what I'm experimenting on at the moment, I was a bit disappointed at the bsiab gain control just being a volume control to stage 2, although i still love the sound of Ed guidry's design. I also wanted to lose the trim on the last section, so replaced the last jfet with an op amp feeding a marshall type tone stack. I'm still playing with these ideas and your circuit  gives me more areas to look at.

[kurtlives]

Would it be correct to assume this circuit has a lot of gain on tap?

[JDoyle]

..you can change the upper fets, since they only work as current sources, and they dont amplify..

Not quite - you may want to check out some of R.G.'s articles on JFETs at geofex.

If you remove the caps to the upper JFETs gates THEN you have current sources...

Regards,

Jay Doyle

[Thomeeque]

Is left pin of C6 really connected this way? Shouldn't it be connected to U1 output?

[dschwartz]

..you can change the upper fets, since they only work as current sources, and they dont amplify..

Not quite - you may want to check out some of R.G.'s articles on JFETs at geofex.

If you remove the caps to the upper JFETs gates THEN you have current sources...

Regards,

Jay Doyle

hmm...from RG keen´s "fooli´n with fets", about the u-amp configuration

Connected this way, the upper N-channel JFET is still helping move the load, but is not contributing any gain itself. Also, since its input has to be driven from the drain of the lower JFET, the lower JFET is now driving the bias resistors of the top JFET, but more importantly it's also driving the JFET source impedance. This loading keeps the max gain down to about 90 even with 10M biasing resistors for the upper JFET.

[arawn]

looks interesting, You might try mpf102's  They seem to sound a little more "tubish" to me

[petemoore]

  It has no trimpots, 2 mu amps and an Opamp.
  That means if you wire it right you don't have to fiddle with other Jfets [though they will alter the sound], and trimpots, and working to get ungatey sounds jibing with the bias arrangements.
  I would ground the inputs on the unused side though, or use a single OA.
  The biasing setup is like what I've chosen for later Mu's.
  Am I not seeing a gain pot value ?
  Looks good from here, TIA for any Sounclips ! !

[dschwartz]

as promised..sound demos!!!!

this is at max gain, very "van halen-ish". some metal sounds too...
http://www.goear.com/listen.php?v=40ed9e2

mid gain strat texas boogie:
http://www.goear.com/listen.php?v=e41fd0c

mid to low gain strat, some nice ZZ top bluesy tones:
http://www.goear.com/listen.php?v=0058946

and lo gain (not at zero, but almost)..note the e string tuning at the end..haha
http://www.goear.com/listen.php?v=69fb734

as you can hear, all gain ranges are usable..

recording setup:
gear:
dui distortion (or preamp, whatever) to multicab sim to sound card..
high gain: jackson jdr94..
the rest is a stock standard series squier strat

enjoy!!

[arawn]

that's just freaking brilliant!! I love it might even have to build one soon.!! excellent worker sir!!

[dschwartz]

Is left pin of C6 really connected this way? Shouldn't it be connected to U1 output?

ussually, the output is taken from the output of the opamp, but not in this case..this way, the gain pot acts as a volume control ,too.