Inverter Distortion

[TejfolvonDanone]

Hi everybody!

I ordered some digital inverters to experiment with (CD4009, CD4049, CD4069, 7404, 74HC04, 74AHC04, 74HCT04, 74LS04). I would like to try them in distortion circuits like the Way Huge Red Llama. I've found out that with the TTL types (7404, 74LS04) you can't bias with a simple feedback resistor but with a voltage divider from Vcc. With this setup i could bais around the threshold (1.3V - 2.2V). Based on the internal schematics i could simulate the it.

But my questions are:
Has anyone tried any of these ICs? In what kind of setup? What was the outcome?

[anotherjim]

Once, 74xx TTL was all we had, and there were circuits using them - squaring fuzzes and dividers, but a 741 amp was usually employed first, then a Schmitt trigger (7414?) then some divider, often a D-type (7474?). If I remember those 74xx functions right then my memory isn't too bad! Afraid I can't think of anything that attempted use them in a more linear fashion.

If you can find them, 74Cxx are basically CD4000 made functionally pin for pin as 74xx TTL. A 74C04 is very much like a CD4069UB. A big functional difference is that TTL tended to choose Low active levels or negative clock edges while CD4000 are active high and positive clock edges.

74HC etc are faster 74C, a lower On resistance for the mosfets meaning higher shoot-thru current meaning lower maximum supply voltage to keep power consumption down.

[TejfolvonDanone]

After a quite big research i've found that people say that these TTL chips (7404 and 74LS04) aren't good sounding at all. I couldn't really tell if they've just put it in instead of the CMOS types or they've done anything else. Looks like i have to try them myself.

Once, 74xx TTL was all we had, and there were circuits using them - squaring fuzzes and dividers,

If these experiments won't work out i'll have to create a squering fuzz.

A 74C04 is very much like a CD4069UB.

I also found that they have the same threshold as the regular 74xx series chips.

If I remember those 74xx functions right then my memory isn't too bad!

Your memory searves you well! 

[anotherjim]

A lot of chip synth circuits can be done with TTL. The Schmitt triggers still make oscillators with one cap & resistor. I can't think of any advantage the original 74xx series has over 74LSxx though. LS is more useful with battery power.

[TejfolvonDanone]

I can't think of any advantage the original 74xx series has over 74LSxx though.

As far as i know they have more current drive than the LS series.