Design Challenge #2

I have not seen the L3 circuit, do you have a schematic? I might have a better idea why they did something if I can see it in context. There is nothing special about positive ground or negative ground.
 
Interesting... For 5 out of the 6 inverters in the two CD4007s, they use only the P-channel devices, operating them single-ended. For that configuration, using -15V power makes sense. I believe they get more gain by running the MOSFET stages single-ended. They run the effects loop driver stage push-pull to get the extra current needed. I run all of the CD4007 MOSFET pairs push-pull in my CMOS Distortion. They use servos for biasing the JFET input amp and all of the single-ended stages. Clever design. Complicated, but clever.
 
Thanks for taking a look, Chuck! From what I could find, it sounds really sweet. From clean to pretty overdriven. I'm kind of obsessed with good sounding SS preamps, so I might try and recreate it (minus the reverb driver and recovery)
 
The L5 is an awesome project! It takes a completely different approach (an OTA is used for distortion), but sounds really good as well! The multifilter stage is also really interesting
 
Can some kind soul point me to C16 on the schematic? I know it's 100nF, but for some reason I cannot find it.

Thanks in advance.
,
 
Can some kind soul point me to C16 on the schematic? I know it's 100nF, but for some reason I cannot find it.

Thanks in advance.
,
Page 9 off of pin 8 of the 4558 schematic says 10nf if your talking about the l5 or

Here for the L3 it is 100nf
 

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Sorry, I forgot there were schematics flying in every direction..I am building..


cmos-overdrive-rev-1-4-png.10082



...using Matt's board. Maybe I missed a revision?
 
Sorry for the confusion. Matt's board is based on v6.2.1 which has a MID control. Look at post #11 on page 1. C16 was not shown on the schematic; it goes in parallel with C15. Here's an updated schematic.

CMOS overdrive rev 6.2.1a.png
 
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Hi.
The Maestro Fuzztain (MFTZ-1) uses a 4007 in the Audio path. Lectric FX just came out with a clone board. Their build docs has a schematic. I think the 4007 is used for distortion.
 
Found the MFZT-1 Service Manual.
According to the schematic, the 4007 is used as a voltage-controlled resistor in the compressor. It is not used to make distortion.

maestro fuzztain MFZT schematic.png
 
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Sorry, I forgot there were schematics flying in every direction..I am building..


cmos-overdrive-rev-1-4-png.10082



...using Matt's board. Maybe I missed a revision?
Excuse me, I seen this schematic and I noticed something weird/knew. Those transistors mosfet type symbol with CD4007 label.
I use Tina TI software to draw schematics, but I can't insert CD4007 to draw the Red Llama schematic.
Is that maybe a sort of trick to "emulate" a CD4007?

Edit: I'm sorry. I confused CD4007 with CD4049UBE. Can I do anything, awnyway to emulate it?
 
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Excuse me, I seen this schematic and I noticed something weird/knew. Those transistors mosfet type symbol with CD4007 label.
I use Tina TI software to draw schematics, but I can't insert CD4007 to draw the Red Llama schematic.
Is that maybe a sort of trick to "emulate" a CD4007?

Edit: I'm sorry. I confused CD4007 with CD4049UBE. Can I do anything, awnyway to emulate it?
I found the parameters for the TINA-TI MOSFET model, but I'm not sure if it is what your looking for. Do you know if the LTSpice models are compatible?

Screen Shot 2021-10-19 at 7.49.33 AM.png
 
Excuse me, I seen this schematic and I noticed something weird/knew. Those transistors mosfet type symbol with CD4007 label.
I use Tina TI software to draw schematics, but I can't insert CD4007 to draw the Red Llama schematic.
Is that maybe a sort of trick to "emulate" a CD4007?

Edit: I'm sorry. I confused CD4007 with CD4049UBE. Can I do anything, awnyway to emulate it?
When you say "emulate," do you mean simulate? I have LTSpice models for the MOSFETs inside the CD4007 & CD4049. I don't know anything about TINA-TI or if the models are compatible.
 
Thanks for your replies, guys.
I'm looking for a CD4049UBE spice to use with Tina TI to draw the schematic of the Red Llama and to see the frequency response, etc. The Red Llama schematic is very simple, and I did some experiments on breadboard, but I'd like to draw it, anyway.
I don't know I can find somewhere the CD4049UBE spice, or I can "build" it with its inner schematic.

I found the parameters for the TINA-TI MOSFET model, but I'm not sure if it is what your looking for. Do you know if the LTSpice models are compatible?

View attachment 17239
Do you think I can use that to get or to create a spice of the CD4049UBE? I don't know if I really can.
 
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