series resistance vs voltage dividers

[caress]

i'm wondering what the difference is between attenuating a signal with series resistance (as between gain stages in a big muff) or with a voltage divider (as the "sustain" pot in a big muff or a standard volume pot)?  are there pros/cons to either or situations in which you should/shouldn't use one or the other?

[kurtlives]

But there is voltage dividers?
Look at the series resistance then notice the "tail" resistor of the bias voltage voltage divider. Also acts like a voltage divider for the signal.

Series resistance usually limits current, also kills highs.

[caress]

ok so there's current limiting as well as high end loss... anything else?

[G. Hoffman]

ok so there's current limiting as well as high end loss... anything else?

Well, any resistor is going to add a bit of noise.  The bigger the resistor, the more noise.


Gabriel

[frank_p]

Can I put in a 3rd case (?)... :
When the pot is partly inside the NF the opamp.
Like, in most of the Marshall dist. pedals. See (1st stage 1st opamp):
http://www.aronnelson.com/gallery/main.php/v/johan_0/drivemaster.jpg.html?g2_imageViewsIndex=1

[Projectile]

Series resistance doesn't attenuate a signal (unless you raise the noise floor so much that the signal effectively disappears). Passive attenuation is usually the result of some sort of voltage divider. So, the answer to your question is that there is no pros or cons because there is really only one way: a voltage divider.

[Hides-His-Eyes]

A series resistor could form a voltage divider with an input impedance though, could it not?

Like a 10M resistor in series before a SHO would halve the signal?

[caress]

Series resistance doesn't attenuate a signal (unless you raise the noise floor so much that the signal effectively disappears). Passive attenuation is usually the result of some sort of voltage divider. So, the answer to your question is that there is no pros or cons because there is really only one way: a voltage divider.

lovely!  it must be some of this

A series resistor could form a voltage divider with an input impedance though, could it not?

Like a 10M resistor in series before a SHO would halve the signal?

that i'm hearing... along with some high end loss = quieter

[DougH]

Series R *is* a voltage divider as there is always a shunt R, whether explicitly set by resistor, input Z of nxt stg, etc. How much do you want to attenuate? If high shunt R, high series R can add noise. Low shunt R will lower Zin of nxt stg, etc which may/may not be ok. These are the trade-offs.

[Projectile]

A series resistor could form a voltage divider with an input impedance though, could it not?

Yup, that's how it works. As DougH stated, there is always going to be a shunt R of some type.