High or low impedience volume pedal with pedals

Discussion in 'Effects, Pedals, Strings & Things' started by soldano16, Feb 1, 2008.

  1. soldano16

    soldano16 Member

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    This is from another forum..

    Is this true. What if you do use a high impedience volume pedal?
     
  2. stinkfoot

    stinkfoot Member

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    A high impedance volume pedal is essential when placed first in line (with the guitar "seeing" the volume pedal directly). It will also work fine after a buffered/active pedal (Boss-type or other pedal left on). A low impedance volume pedal will be a little smoother than the high z version when placed inside the chain (after a buffered pedal), but will damage the tone severely if the guitar is plugged straight into it.

    /Andreas
     
  3. pgissi

    pgissi Member

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    A low impedance volume peal is strictly for keyboards and synths which have a low impedance unbalanced output, do not use one for guitar, it will seriously degrade tone
     
  4. willyredeemed

    willyredeemed Member

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    yes, had a FV-50L and it sucked A LOT of tone, no kidding. heard that you can use buffer before or after it and it will maintain the signal, tho. still not worth it for me, however. i removed a volume pedal all-together from my pedalboard.
     
  5. soldano16

    soldano16 Member

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    On my rig I only use the volume pedal when I'm using fuzz or OD. Those three pedals are on a sepate loop.

    I put my volume pedal at the end of my fuzz/OD loop, to act as a master volume for my dirt pedals.

    So which type is best in this situation? Is the fellow I quoted above basically wrong?
     
  6. pgissi

    pgissi Member

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    yes he is technically wrong.

    You could use a low imp vol pedal and yes using it later in the pedal chain with a loop and/or buffering type pedal pre and post the thing, will minimize the impedance issue but its going to affect your tone either way

    There may be a way to may it work and it would involve something called a line driver, an expensive buffer. Used on large stages in pro rigs

    But why pay several hundred bucks to use a $100 or less vol pedal

    I would go with a vol pedal for guitar exclusively and besides the proper impedance, the taper of the internal volume pot will be more suited to the guitar signal and the human ear.

    They are typically Audio taper pots so they are equal over the turning range of the pot. Not sure if the low imp variety is.
     
  7. stinkfoot

    stinkfoot Member

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    If your fuzz/od pedals will always (regardless of which of them is on at the moment) present a low impedance signal to the volume pedal, you could use a low impedance volume pedal. As long as the output impedance going into the volume pedal is low enough (which most normal guitar pedals will provide) the volume pedal will not harm the tone at all. Most pedals have an output impedance of 1Kohm or less, which is just fine for the 25K pot in the low impedance volume pedal. Fuzz pedals can be tricky, though - some of them don't have output buffers, and can be much more sensitive. So it depends on the pedals in question, really. If you want to be on the safe side, go for the high impedance version.

    /Andreas
     
  8. walterw

    walterw Gold Supporting Member

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    allow me to agree with your premise and dispute your conclusion. a high impedance volume pedal (pretty much always 250k, right?) will still suck a little tone if placed directly after a passive guitar, by loading down the pickups. after a buffer, it will not hurt the sound, but will offer a poor taper, acting more like an on/off switch. so to me, that means it's worthless either way!

    a low impedance pedal placed after a buffer will have a useful sweep and no tone loss. most run-of-the-mill buffered output boss or ibanez pedals in front of the low-impedance volume pedal will do the job just fine, as will putting the volume pedal in a typical amp's effects loop.
     
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  9. Ed Reed

    Ed Reed Senior Member

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    That was my quote. If you don't believe me go over to HRI and ask David Phillips (rackdoctor) he owns LA Sound Design http://www.lasounddesign.net/, he knows what he's talking about, he builds pro board all day long. I can't help it if some guys here have incorrectly hooked up high and low Z volumes and they didn't work right. If they are hooked up right each has a place they work well.

    In fact here is a link to one of his threads http://www.hugeracksinc.com/forum/viewtopic.php?t=41509&highlight= the board pictured there in deed has a low z volume pedal on it in the middle of the signal chain. As I said "ask him, he knows".
     
  10. soldano16

    soldano16 Member

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    I have NO problem with my pedal taper. I guess because the EB VP jr has a toggle switch to pick the sweep you want

    On my board, the loop with the volume pedal has 3 true bypass pedals. I never use the volume pedal loop unless I'm using one of the pedals.

    So in my situation, do I have the right pedal?
     
  11. Ed Reed

    Ed Reed Senior Member

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    Not to beat a dead horse but it's really only wrong if you arn't happy with how it sounds.

    No joke, contact David Phillips, he's cool and very easy to talk to.
     
  12. KagakuNinja

    KagakuNinja Member

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    Exactamundo. This is what I do (or did, until my buffer died, I am using a SHO as a buffer at the moment, a bit of overkill)
     
  13. soldano16

    soldano16 Member

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    It sounds good. Could it sound better?
     
  14. pgissi

    pgissi Member

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    A low impedance volume pedal works no doubt for some, maybe its dependent on the core tone (cleaner versus overdiven) but the only way to know if a high imp pedal sounds better for you is to try since there are variables not considered here like buffering before or after the vol pedal.

    In the post below, the low imp vol pedal refered at the link to is post a Boss Compressor so its been coupled to the guitar by a pedal with a hi imp input for the pups.

    I would think it would be a problem, to what degre is unknown, if you had the low imp pedal as the first in your chain and/or with no buffering after (post buffering may compensate for a low imp pedal 1st to some degree) and the only way to know is to a/b and once again, it may be better for a certain target tone.

    I am think tones bordering on clean to slightly dirty would be less affected.

    Lastly, if your not so sure yourself about it and maybe are overcompensating elsewhere in the signal chain and may not be aware of it, explore it more.

    In Leui of fancy test equipment to determine the answer, your ears will do. Buy one and return if your results dont satisfy.

    Let us know how it works out and what tones are you going for

    Country blues, rock, metal etc,

    I think this has a bearing on how impedance affects and works for the targeted tone in the pedal chain with my money on tones that are on the cleaner side of things verus heavily overdriven tones.

    I can see a low imp working in the fx loop but in my world its a shunt to ground, throwing away tone and not practical since I dont want to stand back at my amp just for that and running cables beyond a few feet is out.


     
  15. fly135

    fly135 Member

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    A high impedance pedal should still have a decent taper after a buffered device. The reason is although it's after a buffered device, it's still going into a high impedance device. Most likely the next device after the vol pedal will be another pedal that designed to have a guitar plugged into it. That means it will be a high impedance input.

    The vol control acts as a voltage divider. If you plug a high impedance pedal into a low impedance input like most line level inputs, then the response curve will be thrown off. But since even after the buffered output you are still going into a high impedance input, the high impedance vol pedal should still work fine. So the designation active or passive really depends on both what's in front and behind the vol pedal. Although you always want passive after a guitar.
     
  16. pgissi

    pgissi Member

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    Not using passive will add tonal coloration that will be characteristic of the active circuitry, for the good or bad it is. Just something to be aware of as with anything that buffers.
     
  17. fly135

    fly135 Member

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    When the term passive is used with a volume pedal it doesn't refer to passive or active circuitry in the pedal. It refers to the type of circuit it's designed to be placed in.
     
  18. pgissi

    pgissi Member

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    you mean this...good info, I go back far enough to where you got one type of pedal, now you have choices

    http://www.ernieball.com/faq_content.php?subjectcode=vol_pedals
    Q: When would I use an active (25k) pedal as opposed to a 250k/500k "passive" pedal, and why?


    A: Passive vs. Active: Whenever there is a passive signal leading into an EB pedal, the 250K or 500K pedal is recommended (mono VP & VPJR 250K and stereo 500K VP pedals available). Whenever there is an active signal (powered preamp in the instrument, effects loop, etc.) leading into an EB pedal, the 25K pot is recommended (stereo VP and mono VPJR pedals available). If an active signal is placed before a 250K or 500K EB pedal, or if a passive signal is placed before a 25K EB pedal, then the consequence may be that the swell of the pedal does not act as designed. Either way, as stated above, try whatever combination you desire, and determine if it works for you. All of our volume pedals are designed to be as transparent as possible in a signal chain. However, whenever you add any component to a signal chain, the signal will change whether it is audible or not. Keyboards are generally served best by the 25k pedals as well.
     
  19. soldano16

    soldano16 Member

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    If my fuzz unit is turned on, is the signal coming out of the fuzz and into the volume pedal considered active now that it's been boosted by a battery powered fuzz unit?
     
  20. pgissi

    pgissi Member

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    Yes, anytime you have a pedal on its buffering the signal and can be considered active. If its not a True Bypass pedal it could be buffering when off also, depends on the circuit. Boss pedals and those like it like the Tube Screamer are Buffering when bypassed.

    The vast majority of soft (electronic) switching pedals are buffering when off.

    The Ernie Ball page suggests using the 250 or 500k pedal if your plugging a guitar that has passive electronics in the pedal as the 1st in the chain. The 250 or 500k pot is what you find in a guitar. Single coils usually use 250k to roll off some highs and humbuckers 500k, so the hi imp pedal is is just duplicating the guitar volume pot in this case.

    If your using the low imp pedal you need buffering before it according the EB
     

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