High headroom Preamp Pedal Schematic Design Help

Feral Feline said:
*Claims to not know how to draw a schematic, draws one when prompted.*



That last sentence I quoted is the key — you have ideas you want to make happen.

That's what got me to finally learn how to read schematics, I had ideas I wanted to make happen.
There's tons I still don't know/understand, but I'm a step closer to making my ideas happen because I learned the basics of reading a schematic and THEN started to breadboard thnigs.

Honestly, that long list of ChatGPT stuff gives me a headache — I don't understand the underlying basic info it's trying to convey.
Would be so much easier to read a schematic to try and help you...

So... TAKE that SCENARIO schematic and break it down and build it back up as your own on the breadboard.

This idea of yours, it's exciting; enjoy your journey.
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Yes! I am currently trying to create a schematics with scenario preamp as my guide. I will post another schematics later. Please help me point out errors guys and suggestions, that would be great!
 
Feral Feline said:
IMO... High-end low-noise op-amps are great for EQs and compressors — anything that's clean where a noisy opamp would degrade your signal.

For any DIRT circuits where you are degrading your signal anyway, well, then any standard op-amp will do: JRC4558, TL072, LM1458...

However, if it sounds good to your ears it IS good, so audition the opamps on your breadboard.
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I see, then I need to order at least 5 of opamps you listed to try it on later. Thanks!
 
I strongly suggest looking at the LTC1144 charge pump if you're looking at that much voltage ... also have you considered using MOSFET instead of JFET?
 
ICTRock said:
I strongly suggest looking at the LTC1144 charge pump if you're looking at that much voltage ... also have you considered using MOSFET instead of JFET?
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I will try to use 18v so i will ditch the booster.

I haven't tried MOSFET yet, but in your experience? MOSFET vs JFET? I am trying to create maybe from edge of breakup to light crunch max for gain character.
 
Hi Guys! I tried to make the scenario preamp work on LiveSpice. Fig.1 is working loaded and tested as plugin pedal on DAW *i use generic opamps. But when i try to use other opamps like op134 , it doesnt work when i try to add the gain stages but it works when i bypass it. Fig2 vs Fig3. Should i just use single generic opams? considering tl072,opa2134 are just 2 opamps inside. Thanks! silently enjoying LiveSPice and LTSpice! Thanks @temol for mentioning this app! love it.

Fig.1

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Fig2
1754153892456.png

Fig3
1754153955940.png
 

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Live spice doesn't like overly complicated circuits, you sometimes have to split things up.

Ive found issues in the past with specific opamps if they're not powered with +/- supplies.

Im still not sure what your ultimate goal is here. Why do you need high headroom.
 
rossbalch said:
Live spice doesn't like overly complicated circuits, you sometimes have to split things up.

Ive found issues in the past with specific opamps if they're not powered with +/- supplies.

Im still not sure what your ultimate goal is here. Why do you need high headroom.
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Higherer is betterer, even if you can't use 80% of it.
 
rossbalch said:
Live spice doesn't like overly complicated circuits, you sometimes have to split things up.

Ive found issues in the past with specific opamps if they're not powered with +/- supplies.

Im still not sure what your ultimate goal is here. Why do you need high headroom.
Click to expand...
Thanks! I tried to reduced the oversamples and now it works. I just want to make a preamp that i can use on fx loop. i want to push more the power amp section, thats the reason i want a higher headroom so it will not just distort early on the front.
 
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hydr41n said:
Thanks! I tried to reduced the iteration and now it works. I just want to make a preamp that i can use on fx loop. i want to push more the power amp section, thats the reason i want a higher headroom so it will not just distort early on the front.
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As a replacement for the amps in built preamp?
 
You're unlikely to run into headroom issues with a guitar signal input and the output required going into a poweramp.

Look at what the Revv G3 and the Firedman BEOD achieve on 9v.

Something to think about with a clean channel is you still want some compression. Spikey transients aren't nice going into the power amp. It's part of the reason people think tube watts are "louder" than solid state watts. Sometimes solid state preamps are too clean.
 
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