4049/4069--CMOS inverter devices

[The Eristic]

I've been meaning to breadboard one of these for a long while as the demos have always sounded really good to me...

I've played it a few times, it does one of the best "extension of amp'" drives out there. Adjusting it is an absolute pain, though, which is why I've never bought one.

[Dandolin]

hmm - anything that sounds similar to you but with more tweak friendly layout?

[LaoWiz]

Not sure if mentioned yet but the Way Huge Fat Sandwich got a 4049 in there. That thing sounded great when I played oldangelmidnight's unit.

[Dandolin]

yass - i ended up scoring one a few years back when i learned it was CMOS and was in my honeymoon phase with the Distortion X. Tripps put so much adjustability into those boxes, and when my used Fat Sandwich arrived it sounded like ass to me. Apparently the previous owner was a bass player who was going for a particularly dark sound (darker even than i would if i was using it with bass), but on guitar it was just...dark...and rubbery.

a quick look @ the manual and some trim tweakery tho and it went right back to the CMOS goodness i'd been expecting

[Dandolin]

cross-posting from the "Stop Not Posting" thread while this one still has life:

https://reverb.com/item/53291348-super- ... es-edition



pretty nice looking build of the ROG "UBE69" (UBEscreamer?) overdrive

[The Eristic]

hmm - anything that sounds similar to you but with more tweak friendly layout?

Not really! All the other CMOS stuff I've played (that I know of) has been pretty different, usually more rough and... hairy around the edges. Apparently there's a madbean for the Blackstone that gets everything including the internal trimpots onto external controls, might look into building that if it isn't too crazy.

[Dandolin]

thanks! yeah - madbean build might be interesting. it seems like the difference in hairiness might come down to highs filtering for each stage/pin of the CMOS chip? i can see why that might be a pita to implement and might significantly influence the tone of these things. luckily for me wrt CMOS inverter designs, i generally prefer hairiness to smooveness, tho as with anything there are shades and degrees....

[Chankgeez]

What do you people think of this professor dude?



https://www.youtube.com/watch?v=4TdM-kuJ-sg

He's lookin' for pedals to dissect. Would a CMOS inverter device be a good candidate?

[crochambeau]

What do you people think of this professor dude?



https://www.youtube.com/watch?v=4TdM-kuJ-sg

He's lookin' for pedals to dissect. Would a CMOS inverter device be a good candidate?

I love Aaron Lanterman's channel, there's also an excellent series on analog synthesis (in addition to the recent stuff about amplifiers). Highly educational (as would be expected from Georgia-Tech).

I don't know enough offhand about CMOS distortion circuits to know if it would be class-worthy, but my take is that he's a genuinely approachable individual who may find amusement in off the wall circuits regardless of it making the grade.

(also, thanks to this thread I have some CMOS ideas chewing on my brain, with luck they won't go full prion)

[Dandolin]

aww !!

[Chankgeez]

Lots of interesting builds gonna be built from this thread.

[Dandolin]

huh - so i had a look @ the guts of a pedal claiming to be a clone of both the Revv G3 and G4 in one enclosure and noticed it was sportin' TLC2274s on both halves of the pcb - which, it turns out, is a CMOS device. So does that mean the Revv G3 and G4 i've been mooching around belong in here too?

whoa, slow down there hoss, not exactly - the real deal uses TL072s and TL074s, which are (dual) JFET opamps - so, maybe kissing cousins at best?

i am kinda interested now in why the cloner thought using CMOS/kinda MOSFET devices was the way to go instead of just using JFET ics like the OG?

[crochambeau]

The TL07n have JFET on the front end, followed by a largely BJT architecture:



The TLC227n is primarily CMOS throughout, we can pick out P channel and N channel complementary pairs along many of the vertical connections:



If you can live with the reduced power supply restrictions (+/- 8 volts for CMOS, +/- 16 volts for the TL07n family) the packages share pinout, and you can just drop one into a layout designed for the other.

While datasheets are not the best vehicle for comparing parts, it would appear that small signal linearity is not a priority guiding the design of the TLC227n.

[Dandolin]

oh - cool - surprised how much of that i followed

[qersty]

What do you people think of this professor dude?



https://www.youtube.com/watch?v=4TdM-kuJ-sg

He's lookin' for pedals to dissect. Would a CMOS inverter device be a good candidate?

this guy's great!