Electra distortion Mod (OD and Distortion in one) help me develop

[Rock_on]

that's the image of the modded Electra distortion im following..

what i will do is Mod the modded Electra Distortion

My target:

* Use it as an OD
* Add a Darlington Pair
* many more coming soon

i studied transistors again, so i learned that a feedback can be produced if reconnect the collector to base again (cant explain. just look at the 10 meg)

an OD works by putting diodes on it's feedback.. by searching for an OD pedal based on a single transistor i saw this here

from here

http://www.diystompboxes.com/smfforum/index.php?topic=89658.0

i'll just a switch maybe dpdt (so i can switch to distortion from OD) or maybe not it's up to you.. never heard of an OD and DS working together at the same time.. yeah i never heard and did...

ok so about the clipping threshold.. i'll just use a trimmer instead. thanks to the person who replied to my last thread..

then i'll remove the distortion control since i can use my guitar knob for it..

then i'll be doing the gain control mod.. i'll put 1k pots in the emitter with a bypass cap..

hmm maybe 3pdt switch is needed i think..

so when the overdrive activates the drive control im about to do is activated also but not when the distortion is active..

that's all

my only real problem is making a darlington pair...

any help or suggestion is welcome... :DD ) ^^

[slacker]

This page shows how to make a Darlington pair http://www.kpsec.freeuk.com/trancirc.htm

If you aren't doing so already I would recommend getting a breadboard then you can try out all these ideas until you have something you like, you might find some of the things you're trying don't work or that some controls are more useful than others.

[Quackzed]

you might need a cap in series with the b2b diodes in the feedback path, thats the way they do it in the muffer circuit anyways, also a resistor from the base of the transistor to ground to set a bias point, this may not be needed but offers some control of symmetry vs. asymmetry of the signal and wheather the signal stays clean and inside the power rails or gets clipped at one or the other rails, a 100k or so from base to ground will offer some softish clipping and second order harmonics before the diodes but it might be getting clipped off at the diodes so it may not matter, but if you had a switch taking the diodes to ground in/out of the circuit , without the fb clippers it would have an odish tone with the resistor and no diodes, then a distorted tone with the diodes in...
if you try it and its too much clipping in od mode you'd swap that 10M for a 1M, that might be a good idea anyhow, 10M might be a bit overkill and not be any different than a 1M anyhow... just some thoughts ,hope it helps. experiment and see what works, in my experience ,with the 100k/ 1M changes and no diodes in the fb loop or to ground youll get a nice compressed overdrive tone that stays on the cleanish side... and with either diodes-cap(10uf) in the fb loop or diodes to ground itll have plenty of distortion either way... moreso than an overdrive would i'd think. hope this helps or gives you some ideas anyhow...

[Rock_on]

you might need a cap in series with the b2b diodes in the feedback path, thats the way they do it in the muffer circuit anyways, also a resistor from the base of the transistor to ground to set a bias point, this may not be needed but offers some control of symmetry vs. asymmetry of the signal and wheather the signal stays clean and inside the power rails or gets clipped at one or the other rails, a 100k or so from base to ground will offer some softish clipping and second order harmonics before the diodes but it might be getting clipped off at the diodes so it may not matter, but if you had a switch taking the diodes to ground in/out of the circuit , without the fb clippers it would have an odish tone with the resistor and no diodes, then a distorted tone with the diodes in...
if you try it and its too much clipping in od mode you'd swap that 10M for a 1M, that might be a good idea anyhow, 10M might be a bit overkill and not be any different than a 1M anyhow... just some thoughts ,hope it helps. experiment and see what works, in my experience ,with the 100k/ 1M changes and no diodes in the fb loop or to ground youll get a nice compressed overdrive tone that stays on the cleanish side... and with either diodes-cap(10uf) in the fb loop or diodes to ground itll have plenty of distortion either way... moreso than an overdrive would i'd think. hope this helps or gives you some ideas anyhow...

so you mean by changing the 10m to another lower value you can make the distortion softer? well if yes.. i'll remove my trimpot and i'll just a pot in place of 10m...

[Quackzed]

well sort of, you also need a 100k from base to ground... then yeah, a 1M instead of the 10M, though i'd try it with the 10M first. if its too distorted for you, try a 1M for the 10M. this is all without the diodes though, WITH the diodes it'll be distorted either way...

[Electron Tornado]

you might need a cap in series with the b2b diodes in the feedback path, thats the way they do it in the muffer circuit anyways,

I had an Electra on the breadboard the other week for fun. You will need a cap in series with the diodes if you want to put them between the base and collector. I used 0.1uf, but try different values and see what you like.   

[Rock_on]

i never thought of that.. so maybe i'll just use a pot on it and think it is my distortion/threshold control...

and... i'll put two dpdt switch in this setup


1st DPDT
-o-o-o- (cap going to base from collector's pin - another dpdt switch - after the collector's cap i mean the 0.1uf)
-o-o-o- (base pin - another dpdt switch - to the ground)

2nd DPDT

-o-o-o- (diode's pin - to the other dpdt switch - another pair of diode's pin)
-o-o-o- (diode's pin - to the other dpdt switch - another pair of diode's pin)


ok sa maybe that way i can make it an overdrive/distortion.. do you think it will work?

is it necessary to use the 100k? cause there is no 3pdt switch in here.. so sad..

is there another way to put 100k from base to ground when in overdrive mode without 3pdt switch? i'll use the another row in the 3pdt switch to put the 100k to ground when in overdrive mode but unfortunately there is none available..


unless 100k to ground may still sound good even if it is in distortion mode... i'll just put it there forever..

[Electron Tornado]

ok sa maybe that way i can make it an overdrive/distortion.. do you think it will work?

is it necessary to use the 100k? cause there is no 3pdt switch in here.. so sad..

unless 100k to ground may still sound good even if it is in distortion mode... i'll just put it there forever..

I didn't use a 100k from base to ground and it sounded fine. It might be fun to try it out, though. Try it with the 100k and without and see if it makes any difference.

Regarding the diodes - the 1N34s don't seem to work so well between the collector and base. The 1n4148s work OK. Try other diodes as well.

This is a very simple circuit, but you have a few things to try out, so take notes on everything you do. It's a good habit for this hobby, and will help you a great deal.

Have fun!

[Rock_on]

ok sa maybe that way i can make it an overdrive/distortion.. do you think it will work?

is it necessary to use the 100k? cause there is no 3pdt switch in here.. so sad..

unless 100k to ground may still sound good even if it is in distortion mode... i'll just put it there forever..

I didn't use a 100k from base to ground and it sounded fine. It might be fun to try it out, though. Try it with the 100k and without and see if it makes any difference.

Regarding the diodes - the 1N34s don't seem to work so well between the collector and base. The 1n4148s work OK. Try other diodes as well.

This is a very simple circuit, but you have a few things to try out, so take notes on everything you do. It's a good habit for this hobby, and will help you a great deal.

Have fun!

may i ask.. what's the purpose of that 100k from base to ground anyway? is that the same as the other amp's (transistor base amp) 1M input (base pin) to ground??

anyway, can you pm me your contact? fb, yahoo or gmail.. anything??

thanks for the quick reply

[Rock_on]

well sort of, you also need a 100k from base to ground... then yeah, a 1M instead of the 10M, though i'd try it with the 10M first. if its too distorted for you, try a 1M for the 10M. this is all without the diodes though, WITH the diodes it'll be distorted either way...

hahaaha i did change my 10m to 1m with diodes still connected.. and it sound like the god of the metal god.. super duper duper duper distorted..


im using a s9014 transistor which is a very high gain preamplifier npn transistor. then i tried to make a darlington pair of it.. then it sounds like god of the god of the metal god.. hahahahahahahahhahaha super funny...

[Rock_on]

This page shows how to make a Darlington pair http://www.kpsec.freeuk.com/trancirc.htm

If you aren't doing so already I would recommend getting a breadboard then you can try out all these ideas until you have something you like, you might find some of the things you're trying don't work or that some controls are more useful than others.

i saw this.. and it is same to the one you gave...

but how about this? is this the same?

[Quackzed]

you can think of the transistors base as being somewhere 'in between' +9volts and ground... when the signal (which is around .2 volts big) is exactly in the middle of +9v and ground (at 4.5v halfway between 0v(ground) and +9v(positive) it can swing up and down without hitting +9v or ground and it wont distort at all, its safely away from the rails, but...
if you have a 1M resistor from the base to a 10k resistor(also connected to collector- ignore this for now)  to +9v  then thats 1,010,000 ohms between the base and +9v, so if you put a 100,000 ohm resistor from the base to GROUND, then the signal is basically not exactly in the middle anymore and will distort a little easier because its closer to ground than to +9v(@10 times closer cause 100,000 is @10 times less than 1,010,000 ohms, so if it swings up 100mv and down 100mv (total 200mv signal) it will start to hit the ground rail a bit because its 'biased' closer to ground... this is how the 100k from base to ground works, it pulls the signal closer to ground and away from the middle of 9v and 0v. so as a booster it will work without the 100k from base to ground but it will be clean, no od. but with the 100k it'll distort a bit and you get a bit of overdrive sound from it, you can mess with how much it clips the ground rail by adjusting the 100k or the 1M to change how close or far away the signal will be to/from the ground rail or the +9v rail. if you swapped the 1M and the 100k resistors, the signal would be 10 times closer to the 9v rail than from ground and the opposite half of the signal would clip the 9v rail. it just happens to be the case with  transistors that they clip softer and smoother at the ground rail than they do at +9v, so clipping at the 9v rail is more harsh or edgy, not as smooth, less od more bzzz. hope that makes sense. its those 2 resistors compared to each other that 'bias' the signal and wheather its closer to 0v or 9v or if theyre equal(say both are 1M) exactly in the middle of the rails.

[Rock_on]

you can think of the transistors base as being somewhere 'in between' +9volts and ground... when the signal (which is around .2 volts big) is exactly in the middle of +9v and ground (at 4.5v halfway between 0v(ground) and +9v(positive) it can swing up and down without hitting +9v or ground and it wont distort at all, its safely away from the rails, but...
if you have a 1M resistor from the base to a 10k resistor(also connected to collector- ignore this for now)  to +9v  then thats 1,010,000 ohms between the base and +9v, so if you put a 100,000 ohm resistor from the base to GROUND, then the signal is basically not exactly in the middle anymore and will distort a little easier because its closer to ground than to +9v(@10 times closer cause 100,000 is @10 times less than 1,010,000 ohms, so if it swings up 100mv and down 100mv (total 200mv signal) it will start to hit the ground rail a bit because its 'biased' closer to ground... this is how the 100k from base to ground works, it pulls the signal closer to ground and away from the middle of 9v and 0v. so as a booster it will work without the 100k from base to ground but it will be clean, no od. but with the 100k it'll distort a bit and you get a bit of overdrive sound from it, you can mess with how much it clips the ground rail by adjusting the 100k or the 1M to change how close or far away the signal will be to/from the ground rail or the +9v rail. if you swapped the 1M and the 100k resistors, the signal would be 10 times closer to the 9v rail than from ground and the opposite half of the signal would clip the 9v rail. it just happens to be the case with  transistors that they clip softer and smoother at the ground rail than they do at +9v, so clipping at the 9v rail is more harsh or edgy, not as smooth, less od more bzzz. hope that makes sense. its those 2 resistors compared to each other that 'bias' the signal and wheather its closer to 0v or 9v or if theyre equal(say both are 1M) exactly in the middle of the rails.

so you mean the lesser the closer??

like the 100,000, it is lesser than the 1,100,000 ohms so that means it is closer to ground??

oohhh so that way i can make my distortion less harsh.. i dont like too much rock.. yeah i like metal sometimes but my pedal is far beyond metal...

so is that why when i change 10m to 1m it became more harsh?? cause it is lesser now?? or is it because i did not follow what you told me before to remove the diodes and put 100k to base and ground?


anyway thanks... i understand now.. im a bit confused though, because of the 10m to 1m change...

i'll try..

[Rock_on]

This page shows how to make a Darlington pair http://www.kpsec.freeuk.com/trancirc.htm

If you aren't doing so already I would recommend getting a breadboard then you can try out all these ideas until you have something you like, you might find some of the things you're trying don't work or that some controls are more useful than others.

i saw this.. and it is same to the one you gave...

but how about this? is this the same?

i asked the other forum and told me the second one is not a darlington.. it was stages.. how idiot i am.. sorry..

[Quackzed]

anyway thanks... i understand now.. im a bit confused though, because of the 10m to 1m change...

hmm, not sure about the 1M being more distorted than the 10M... it must be because you also had diodes in it, though if they were back to back to ground after the cap it should still be less gain with 1M.... if they were in the feedback path with a cap they might conduct more with the 10M as the 10M lets less current around the diodes, that must be it... ? not sure.

[Rock_on]

anyway thanks... i understand now.. im a bit confused though, because of the 10m to 1m change...

hmm, not sure about the 1M being more distorted than the 10M... it must be because you also had diodes in it, though if they were back to back to ground after the cap it should still be less gain with 1M.... if they were in the feedback path with a cap they might conduct more with the 10M as the 10M lets less current around the diodes, that must be it... ? not sure.

i didn't change my ds pedal to od.. i just tried lowering 10m to 1m. that's the only mod i did, and i put a 100k from the input to ground (which is connected to the base also)..

well when i put the 100k my ds didnt sound softer still with the 10m...

abotu the 1m, that's a mystery.. it became more distorted.... mystery, let's just call scooby doo or sherlock holmes. hahahaha

[Rock_on]

no.. i was wrong.. when i put 100k with 10m it is much better now

i built the deluxe bass fuss blue led is used and two s9014 is used to make a darlington pair..

i put my guitar's volume all the way down (i have treble bleed mod which means it doesnt lose it's highs) and it's sound is the same with the electra distortion but on the mid gain only or maybe mid of mid gain.... with my volume all the way up....

now i love my electra distortion than before.. hahaha

im building the 5th gear overdrive now.. it is my 3rd pedal...


EDIT:

sorry for many mistakes i always do. now i know why.. i forgot to put an emitter resistor

[Quackzed]

cool glad you got it where you like it. fwiw, the emittor resistor can control the gain, so a bigger emitter resistor = less gain, a smaller one = more gain.
just in case you wanna play with the gain, or even add a gain control.

[phazon]

Knowing that this is an old thread, I have been wondering if you can use diodes for clipping by putting them somewhere in a a mosfet or jfet based circuit similar to these

https://www.tubecad.com/2017/04/blog0377.htm

http://www.muzique.com/lab/boost.htm

[GibsonGM]

Yes, Phazon, you can add clipping diodes at the output of JFET or MOSFET based boost circuits, just like they did with the Electra!   As long as the thing is amplifying enough to forward-bias the diodes, they will turn on and clip your signal.    Taming the tone is up to you, though!   

Note that you place them after the output cap to keep DC off them.  Look up "Distortion +" schematic to see how it's done with an opamp...