2 stage Electra help needed

[ljoe1969]

First I am a noob. I would like to put two Electra's together into one circuit. Could someone tell me how to do this? I have two of them bread boarded, when I connect them with a jumper wire I get all kinds of noise.

Thanks in advance.

[antonis]

Do you connect them is series (first output to second input) or in parallel (adding individual outputs) ..??

Are there any out (vol) pots..??

If yes, what is their value..??


P.S.
If you try to distort an already distorted signal by exactly the same way you'll not practically notice any difference...

You better try to "alter" first stage's distortion - like move the pair of diodes between the Collector and Base of BJT (changing also the biasing resistor to something like 470k) and connect them via a - say - 10k resistor...

[duck_arse]

ljoe, draw the circuit (the one you're using, the one you're thinking of, doesn't matter), then show it to us.

[GibsonGM]

ljoe, draw the circuit (the one you're using, the one you're thinking of, doesn't matter), then show it to us.

^ would be very helpful.

To add to Antonis' reply.....if you try to amplify something that is already "maxxed out" in amplification, you multiply the signals (if in series)....and in trying to do so, you can get some VERY weird, uncontrollable oscillation.....you might be asking an already-high signal level to be amplified by 1,000 or something, which the power supply simply cannot do, and the resulting draws on the supply lead to massive protest (for lack of a better word).

There ARE ways to cascade gain/distortion stages, though!  I'm sure once you get a pic up, you'll get LOTS of advice, about interstage attenuation and the like.   Neat idea to play with. 

[knutolai]

A modification you could do is remove the diodes of the first electra distortion and make the diodes of the second Electra distortion switchable. Without the diodes it sound pretty sweet IMHO. On the first volume pot you could add a 1k resistor between lug 1 (the lug that would normally go to ground) and ground. This way you wont kill the sound completely when you turn it to minimum (similar to most pedal-format gain controls)

also it helps to supply the schematic when you need help with a circuit. Im guessing

if you try to amplify something that is already "maxxed out" in amplification, you multiply the signals (if in series)....and in trying to do so, you can get some VERY weird, uncontrollable oscillation.

That sounds odd. Im no expert by far, but Isnt amplifying a signal that is already "maxed out" just another way to achieve distortion? Like feeding your tube amplifier preamp with a boosted signal to achieve saturation?

[ljoe1969]

yep. that's the schematic i am using. i did not use any pots at all, and i ran the two electra's in series. i get a lot of noise, but it still works and to me it sounds good.

[GibsonGM]

"That sounds odd. Im no expert by far, but Isnt amplifying a signal that is already "maxed out" just another way to achieve distortion? Like feeding your tube amplifier preamp with a boosted signal to achieve saturation?"

I don't usually go way in depth for 'new folks' since I don't want to confuse them, or bring up a lot of stuff they may not know much about.  So I draw these analogies, which at times may sound kind of....stupid, LOL.  I try.

Amplify a signal from say .5V to 5V.  Nice distorted output, as from the Electra.    Now feed that 5V to the next stage...even if that signal is clipped, flat-topped, it's going to hit the next stage hard...and pretty badly, in my experience.   You overload the input (how much can a BJT swing?? LOL  Not enough headroom for the signal you're inputting, and the power supply doesn't have enough room).   

So, by "maxxed", I meant fully clipped by the first stage.  The next stage will just get overloaded.  Transistors sound like poo when you go too far with this - probably more my opinion than fact, but grossly overloading an input here shouldn't sound good.  Rarely (ever?) does taking the output from one distortion pedal and giving it to another one sound good....I'm glad you like it, ljoe...must be really fuzzy and not reproducing notes clearly?  The standard I'm using is "definition of notes".   I'd love to hear a clip.  What I'm saying isn't gospel, by any means...some ppl talk about 3 hard clipping stages like this, and have reported ok results...

Hitting your tube amp with TOO MUCH signal will just result in a totally square, rectified output that sounds like total @ss; perhaps 1 or 2 ppl would like it, tho.  "Into the Black" by Neil Young.  Giving it a boost that's within 'certain parameters' is NICE and very desirable, of course!!   A quick look at a load line shows this pretty well.

I mean this from the point of view of the active device and not just tonally...there is a point where you overdrive a device (tube, BJT, FET...) and nothing more is happening...saturation....you can try all day, and the shape of the wave doesn't change, holding all things the same. 

[knutolai]

...I mean this from the point of view of the active device and not just tonally...there is a point where you overdrive a device (tube, BJT, FET...) and nothing more is happening...saturation....you can try all day, and the shape of the wave doesn't change, holding all things the same.

I get your point I think I just misunderstood your phrasing.

...but it still works and to me it sounds good.

well then whats really the issue?  as pointed out your oversaturates your sound. Maybe by lowering the gain (pot between the electra distortions) you'll still get a favorable sound, but without all the noise and chaos surrounding it. give it a try!

[ljoe1969]

is there a way to upload an mp3? i can give a sound sample if so.

[duck_arse]

I was thinking about this (no good will come). if you put 2 electras front to back, each with output level pot, and have a single set of b-to-b diodes on a switch that switches between either the collector of the frist stage, or the collector of the scond stage, then you would have a boost into an overdrive, or an overdrive into a boost. (both stages have the required series 10k before the diode point, natch.)

any takers?

[knutolai]

I was thinking about this (no good will come). if you put 2 electras front to back, each with output level pot, and have a single set of b-to-b diodes on a switch that switches between either the collector of the frist stage, or the collector of the scond stage, then you would have a boost into an overdrive, or an overdrive into a boost. (both stages have the required series 10k before the diode point, natch.)

any takers?

Thats similar to what I suggested. Sounded pretty good IMHO

[pee-j]

hi,
(different time, different ear but the same circuit )

I landed here cause I was searching for this..

cause I thought of doing "this", too...

as I imagine: the idea is about "cascading" two stages like in the BMP ...

of course, the signal need be lowered after stage one... back to nearly the original..
but that's as far as I can imagine it

and I understand Antonis's remark:
"If you try to distort an already distorted signal by exactly the same way you'll not practically notice any difference..."

but the level doesn't have to be the very same... there could be 2 gain and 2 vol pots..
but I'm no expert, apparently

I don't know what good could come out of this
but the Electra is so good that one will think let's go on deeper into shaping the tone.. be it more of overdriving or distorting...

this is how I approach the idea

...

[soggybag]

I feel like putting two Electras back to back would give you more compression and start heading into Big Muffish territory.

Where I think the Electra could be improved is adding an output buffer. Like the last transistor stage on the big muff. Maybe include the big muff tone stack and the last transistor?

[Locrian99]

Hadn't see this simple little schematic before, i may have to breadboard this and run it into my ruby.   Make a little dirt switch for it.   

[andy-h-h]

Have you checked out the EQD Special Cranker?   Might be of interest as it's quite a similar idea.   

Build docs and schematic in pedalpcb. https://docs.pedalpcb.com/project/SpecialK-PedalPCB.pdf

[antonis]

as I imagine: the idea is about "cascading" two stages like in the BMP...

Good idea - tricky implementation..

You see, Electra's output impedance is 47k (Collector resistor value) for output amplitudes lower than diode pair clipping threshold where its input impedance is (h_FE x 680) // (2M2 X [680/47k + 1]) (about 32k..)
So, the signal coming into the 2^nd stage is attenuated by 60% (1.8V for 4.5V 1^st stage output..) leaving enough margin for further amplification toghether with a HPF (100nF/32k) of about 50Hz..

So, it could be a good idea a 2 stage Electra with 1^st stage diode pair wired with a switch to GND..

[nocentelli]

hi, (different time, different ear but the same circuit )

I landed here cause I was searching for this..

The EHX Ripped Speaker fuzz uses exactly this x2 cascaded, diodeless electra to generate the fuzz sound. Pedalpcb has traced it out here:
https://docs.pedalpcb.com/project/PaperScratcher-PedalPCB.pdf

....although it also has a buffer upfront, another transistor stage with a bias-twiddling pot to get some gated sounds and an interesting opamp-based active version of the BMP tonestack on the end.

You could just snip out the middle pair of transistors for a basic schematic of what you are after, i.e.




...but with a 100k volume pot tacked onto the end.

[pee-j]

hi guys,

for several months I kept it in mind that you just don't put two electras in series...
seriously
however, just a few minutes ago I saw this video (a very cool podcast), about electras...
and they go into Love Pedal's Tchula project...
which is two electras...
it is no contradiction to your expert reactions though...
cause the first one doesn't go from 0.5 to 5V, but say only to 3...
anyway, here's the video...  from 5:00  https://youtu.be/WzO7r3Jelbs?t=300

[GibsonGM]

Yup, sounds good!  The best way to see what happens if you cascade 2 overdrives like this...is to just do it!    

He mentions that he set the 1st one for about half gain, and then sends it into the 2nd electra.    That's classic gain staging...setting how hard you want one stage to hit the next.   Nothing wrong with that in ANY way.    The signal isn't 'totally squared off' coming out of the 1st circuit, so there's still something left to work with for the 2nd. 

I think what I wrote way back then still holds, tho I could've been more clear I think. I was referring more to uncontrolled fuzz feeding fuzz/dist.  This is all about how much you clip in each stage and how much you drive the next stage.  If you have some headroom left to give the 2nd stage, that's fine, and you also have a chance to tweak coupling caps...to make sure you don't have too much bass content, which may make bad mud tone if not adjusted.   The Electras may not do this, but some ODs will, just requiring a smaller input cap on one or both circuits to taste.

Same principle as using an OD to hit preamp tubes with a hotter signal. You could also play with the diodes here....maybe try 1N4148s in the 2nd one, or LEDs, that could change up the tone and also give a larger signal output.  2 in series sounds like a fun tweaking opportunity!   

[Mark Hammer]

It was my understanding that the EQD Special Cranker WAS essentially two cascaded Electras.
http://effectslayouts.blogspot.com/2022/05/earthquaker-devices-special-cranker.html