SOLVED Delegate has a siren sound in the background

[diregummybear]

So my delegate pedal has developed a siren sound that is louder when used with a drive pedal. It comes through in the noise floor whenever the pedal is powered on. The sound gets louder in certain positions of the volume knob. Any ideas on what is causing this?

 

[Betty Wont]

What did you use for the charge pump? The wrong 1044 will make an audible whine.

 

[diregummybear]

What did you use for the charge pump? The wrong 1044 will make an audible whine.

Hey there! That is a good thing to check now isn't it? I will do that as soon as I can.

 

[diregummybear]

What did you use for the charge pump? The wrong 1044 will make an audible whine.

 

[Betty Wont]

Hrm... I'm not familiar with that particular chip. I use this https://stompboxparts.com/semiconductors/tc1044scpa-charge-pump-ic/
Specifically you are looking for the SCPA suffix. That is the one known not to introduce audible whine.

 

[Robert]

The switching frequency of the LTC1044ACN8 is 5kHz, that's most likely going to be the problem.

 

[diregummybear]

Thank you all. The charge pump IC did in fact cause the issue. Thanks for that!