Volume pedal impedance question

[spargo]

I currently have a Boss FV-500L low impedance volume pedal at the very end of my signal chain for volume (this pedal also has an expression jack).  I also have an Ernie Ball VP Jr 25k volume pedal, which I use as an expression pedal for a Timefactor.

I'm wanting to switch my volume pedal to the very FRONT of my chain so it's before my delay.  But it seems both of the volume pedals at my disposal are low impedance, when at the front of the chain it should be high impedance.  Is this correct?  What negative effect on my tone will happen if I were to use one of these at the front of my chain? (it doesn't matter so much which one to me, since I can use either as an expression pedal)

Would it be better to go from guitar > compressor > volume?

I suppose if needed I could always sell/trade one for another.

[Hides-His-Eyes]

The pedals are both low impedance. However, a simple buffer in a 1590A at the front of your chain will allow you to use a low impedance pedal.

[kvandekrol]

Volume after compressor is a very good idea. You'll have smoother swells, especially if the sustain is turned up on the comp.

[petemoore]

  Scenario suggestions [not necessarily implementation suggestion...
  Two volume pots in a row ? [drawing schematic actually is easier to leave the question mark out]. 
  Say they're both the same value.
  Would mean 1/2 the resistance to ground.
  Would mean 2x the signal path resistance.
  ...depending on the settings of course, can be ballpark-thought-through...look at [or for anaccurate measurement, measure] the pot positions you set.
  Options:
  Get rid of a duplicate volume pot', use treble bleed cap across large SP Resistance[s.
  [many volume treadles have room for a fair amount of extra's, perhaps re-do the entire 'schemata section'...make more room while getting rid of a couple jacks and a box and anything redundant.]
  Use a buffer when it benefits the tone by way of improved impedance match, such as when encountering loading effects.
   

[fxseth]

Hi,

You want the pedal after your guitar to have a high input impedance so that the signal from the pickup appears across it.  If it is too low of impedance, you will start losing a lot of the signal.  Try running the pedals with it plugged in and then remove it completely and see if the difference in sound bothers you.

Usually, a buffer pedal has a high input impedance and a low output imedance. 

I found the schematic here:
http://img818.imageshack.us/img818/180/fv500l.jpg



You probably could put  a higher value resistor between the two pots.  Then the voltage across the volume pedal would be higher.  The only problem would be that the voltage range you control would be reduced.

[spargo]

I swapped the FV-500L to be used as my expression pedal, and put the EB VP Jr. 25k after my compressor and a boost and played it for a couple hours.  Sounded fine to me.  Putting it after the boost allows me to have massive gain swells with the boost cranked up.

[dmc777]

Why don't you just put either one of them Last in your chain but Before the delays? Or last in chain>buffer>volume>delays?