GGG Neutron build noise question.

[skiraly017]

Having finally gotten my Neutron build up and running successfully with the charge pump, I have a question regarding noise. In lowpass and bandpass modes with the range switch in either high or low the pedal sounds fine but highpass mode seems to introduce a fair amount of unwanted noise, especially with the range switch in the high position. I don't think it has anything to do with the project I think that's just how the circuit is, however I do not have a MuTron to compare it with so I was hoping for confirmation from other Neutron builders or MuTron users. Although the highpass position is not one that I would use regularly I'd like to know that I got the build right.

All that being said, this is one of the best filters I have played, it just sounds right. Thanks R.G. and JD.

[R.G.]

Noise is "any unwanted signal".

I your noise:
(a) hum
(b) whining
(c ) hiss, like escaping steam?

If c, it's the nature of the beast. Any treble boost boosts whatever thermal noise that's already there. You may be able to lower it by more judicious choices of parts or values.

[skiraly017]

Noise is "any unwanted signal".

I your noise:
(a) hum
(b) whining
(c ) hiss, like escaping steam?

If c, it's the nature of the beast. Any treble boost boosts whatever thermal noise that's already there. You may be able to lower it by more judicious choices of parts or values.

Letter "C". It's not unbearable, I just don't have anything for comparison. There were no deviations from the bill of materials included in the project file so I'm inclined to go with it's the nature of the beast rather than a build error.

[skiraly017]

I wanted to revise my original statement, it's when the sweep is in the "Up" position that I get the noise. Nothing unbearable, just wanted to make sure I got it right.

[lowstar]

in my neutron build, there also was some noise, also only in the high pass position if i remember correctly. i had a faint whining, i´m sure it had to do with the charge pump. since i´m a bass player and the high pass position is uninteresting for me anyway, i ditched the bp/hp/lp switch, hardwired it to lp, used the free space on the enclosure to install a volume control instead that utilizes an inverting opamp gain stage and made it true bypass.

cheers,
lowstar

[skiraly017]

Pretty shure this isn't charge pump noise as it happens with two 9v batteries as well. I think it's just the circuit.