Author Topic: Increasing Output/Volume (not gain/overdrive) of Electra Style Circuit?  (Read 529 times)

chumbox

Hi All

I'll preface this by saying I've had a search and read similar topics but still a little unsure what my best option is for these simpler circuits where you don't have as many parts to mess with like Tube Screamer schematic.

Each time I build an Electra style circuit, which I realise are very low gain/output, I find I'm always running the volume somewhere between 3/4 and flat out just to get unity, especially with certain diodes.  Is there an 'elegant' option for increasing the output with minimal (I understand there will be some) impact on the tone?

I read that potentially a clean boost circuit is an option (but which type?), and removing/changing the diodes would be an option but the tone will change greatly.

Any advice appreciated
 

antonis

Re: Increasing Output/Volume (not gain/overdrive) of Electra Style Circuit?
« Reply #1 on: February 09, 2018, 06:54:27 AM »
till Sir Mike comes together with his MosFet booster solution.. :icon_wink:

Low Volume means low signal level for which is mainly responsible diodes clipping threashold..
(unless of course your specific gain setting results in a lower than diodes Vfd signal voltage..)

Diodes clipping is a "brute" behavior and you can't face it using "elegant" ways.. :icon_wink:
Adding a extra series pair on existing diodes or changing them with another pair of higher Vfd should indeed improve volume level but it would affect the "hardness" of clipping..
(it will raise clipping threadshold hence leaving more space for signal waveform curve before slope cut-off - the higher the clipping threashold the "softer" the clipping..)

I'd propose some kind of boost/recovery stage (e.g. like Big Muff final BJT amp) but it might be an overkill for such a simple circuit like Electra style..

edit: When you speak about Volume pot setting do you refer on Guitar pot or you've placed such a pot on your circuit output..??
« Last Edit: February 09, 2018, 06:58:48 AM by antonis »
Can't follow your signature changes, Stephen..!!

GibsonGM

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Re: Increasing Output/Volume (not gain/overdrive) of Electra Style Circuit?
« Reply #2 on: February 09, 2018, 08:21:48 AM »
Antonis is making fun of me again  ;) 
but yes - you could follow the Electra with a boost such as the Mosfet Boost, or a BJT recovery stage, an opamp...whatever gain stage you like.   They will all do the job.   Some will color your tone a little, which is why you see some suggesting opamp, some like the Mosfet (me)...some like JFET....by experimenting, you will find what you like.    This may a good project to do that with - you may spend more time on the boost than the input stage, ha ha....which is great!

Antonis also suggests a way to increase the Electra's apparent volume, by adding one (or more!) diodes in series to each of the clipping diodes. This will make the threshold of clipping higher, and of course that allows more of your signal level at the output.   It will result in "less distortion", however.    It is a much easier thing to do, though!   Be sure to try it.   

The drawback of a 1-stage effect like the Electra is that is does not generate enough level to do additional 'useful things' with.   It is simply, but you can't do much to modify it without adding more parts.    IMO, it is more of a clipping stage than a complete effect, but for some that is enough.
MXR Dist +, TS9/808, Easyvibe, Big Muff Pi, Blues Breaker, Guv'nor.  MOSFace, MOS Boost,  BJT boosts - LPB-2, buffers, Phuncgnosis, FF, Orange Sunshine & others, Bazz Fuss, Tonemender, Little Gem, Orange Squeezer, Ruby Tuby, filters, octaves, trems...

duck_arse

Re: Increasing Output/Volume (not gain/overdrive) of Electra Style Circuit?
« Reply #3 on: February 09, 2018, 08:57:27 AM »
here's an idea - take the diodes outta the electra, and listen to the nude tone. any good? if so, put the diodes back in, and build a second electra w/out the diodes as a boost to follow the first. you can put the volume pot either after the diodes, or after the second electra, there may well be a usable difference in the two positions.
now you can get vintage spanners - who knew?

antonis

Re: Increasing Output/Volume (not gain/overdrive) of Electra Style Circuit?
« Reply #4 on: February 09, 2018, 09:20:17 AM »
Not a bad idea Stephen but shouldn't that increase total distortion..??
(unless second Electra has a gain of less that 15db or so..)
Can't follow your signature changes, Stephen..!!

duck_arse

Re: Increasing Output/Volume (not gain/overdrive) of Electra Style Circuit?
« Reply #5 on: February 09, 2018, 09:56:32 AM »
I dunno. that's why OP is going to listen nude!
now you can get vintage spanners - who knew?

karbomusic

Re: Increasing Output/Volume (not gain/overdrive) of Electra Style Circuit?
« Reply #6 on: February 09, 2018, 01:34:34 PM »
Quote
here's an idea - take the diodes outta the electra, and listen to the nude tone. any good? if so, put the diodes back in, and build a second electra w/out the diodes as a boost to follow the first.

That's exactly what I did with mine and worked wonderfully. :) It's possible I tweaked the second stage's gain a tad but either way, worked great.

iainpunk

Re: Increasing Output/Volume (not gain/overdrive) of Electra Style Circuit?
« Reply #7 on: February 10, 2018, 01:27:24 PM »
I've build my electra as a triple electra where only the middle gain stage has diodes, and there was a bass cut (shelved, -12 db, @ 700 hz) between the 1st and 2nd stage to reduce fuzzyness. I clipped with a red and green LED. Sounded great, output in spades. Shame i gave it away.
If we don't study the mistakes of the future, we're bound to repeat them for the first time.
-Ken M

chumbox

Re: Increasing Output/Volume (not gain/overdrive) of Electra Style Circuit?
« Reply #8 on: February 14, 2018, 04:39:50 AM »
Thanks all for the replies! I've been trying a few of these ideas and finding the BJT stage really sounds good for this purpose, keeping things pretty flat but I also liked a similar deal with a MOSFET.