Taming unwanted noise in a 4049 based dirt pedal.

[skiraly017]

Using a Red Llama for example, I'm referring to the hiss level at idle with the guitar volume rolled off. It's not a grounding or construction issue and I've had it happen using different layouts (yes, I used the CD4049UBE). I though maybe if you used more of the invertors but found this statement about the ROG Double D -

"We tried using all six stages in series, but the level of hiss was incredibly high. Good tones were there, but the noise level was too much. We discovered the maximum limit for a well-behaved circuit was around four inverters in series. Even then, the noise was pretty high."

Is there anything that can be done or is this just the nature of the 4049? Thanks.

[skiraly017]

Bump. Still curious. 

[anchovie]

It's the nature of the 4049.

[zach]

Have you already tried grounding the input with a 100k resistor?  That took care of the noise for me.  I would also check any other chips you're sharing ground with. 

Also added a diode between the output and one of the unused stages, which seemed to get rid of the low pass portion of the schmitt trigger.  I can't explain that at all.