how to unbuffer the signal?

[mr_doyle]

hello,

i need to connect a fuzz pedal after a buffer (this can not be avoided) so i'm wondering how could i unbuffer the signal.
I guess there's a transformer involved...
I've seen the article on pickup simulation on muzique.com and i'd give it a try, but any other suggestions are more than welcome.

D.

[Melanhead]

what's ahead of it with a buffer in it ?

[mr_doyle]

it just doesn't "work", sounds awful: so i'd like to put an "unbuffer" before the fuzz input

hope this makes sense,
D.

[Melanhead]

Yup I got that, but what "buffer" are you running through ? Is it a pedal or something like a GCX unit ? Just wondering why it can't be avoided.

[Mike Burgundy]

Once the buffer's there, you can't just take it out - well, remove the entire pedal, yes.
What you want is something that fools the electronics into thinking they're seeing a pickup.
Have a look at the pickup simulator at AMZ. That might help.

[Sir H C]

A buffer lowers the driving impedance, the only thing I can think to do is add a series resistor with the output of the buffered pedal or in series with the input of the pedal you want "unbuffered".  Even that is faking it.

[Plectrum]

A buffer lowers the driving impedance, the only thing I can think to do is add a series resistor with the output of the buffered pedal or in series with the input of the pedal you want "unbuffered".  Even that is faking it.

In this instance, couldn't you could make a patch cable with the resistor inside?
I also think a transformer may be the best option here though. If you make the amz circuit, I'd like to know how it turns out...

Grant.

[Sir H C]

If you use a transformer, you are also altering the voltage that the signal is at.  For instance if you assume the source impedance is 600 ohm, and you go to 10k, you increase the voltage by 4x.  Truthfully the only way to "unbuffer" is to create a crappy buffer.  Since most poor buffers are emitter followers, these have uneven impedances for sinking and sourcing current.  And none of these will truly emulate the pickup going into a low impedance pedal.

[David]

Which fuzz pedal?  A Fuzz Face?

[Bernardduur]

Search around for the schematic of the Bazz Fuss; it has an transformator in front of it (connect only one half of the trafo) to make the signal unbuffered (I thought it called something like a "pickup simulator"). I use one before my "buffer hating pedals" and it works great!

[d95err]

Use a true bypass box and connect 100 metres of feet of poor quality guitar cable before the fuzz! 

(I once saw a truly analog delay that was made of a 100 meter garden hose...)

[bwanasonic]

Is a bypass switch/ loop box not an option for the buffered pedal? I keep my buffered pedals in a loop that can be switched out.

Kerry M

[Paul Perry (Frostwave)]

Sir HC is right, stick a resistor or pot in series. If you are experimentally inclined (and who here isn't? ) put an old pickup coil in series as well.

edit: yes, I can see a problem with putting the pickup in series..... but try it anyway!

[mr_doyle]

thanks for all replies guys: pedal is a Fuzz Face clone with germanium transistors, and buffer can't be avoied as it's built in in the switcher.
i know that it is possible to "unbuffer" the signal and that there's a "better" way that a resistor, so i thought at the pickup simulator.
i'll try to build it, will see if it works.

just wondering, does the sound of wah pedals change behind a buffer because of impedance as well?

thank you,
D.

[Paul Perry (Frostwave)]

just wondering, does the sound of wah pedals change behind a buffer because of impedance as well?

Certainly, some early wah designs had a low input impedance.
www.geofex.com/Article_Folders/wahpedl/wahped.htm

[mr_doyle]

Thanks Paul,

so such an "unbuffer" device could potentially solve that prob as well...
so me want to investigate more on the subject :-)

D.

[Melanhead]

and buffer can't be avoied as it's built in in the switcher.

D.

If it's a GCX switcher or similar with a buffered in there's a way around it ... plug the guitar into the in of the first loop ( fuzz in this loop ) take the output of loop 1 and run that to the buffered input ... if not then forget my reply

[amz-fx]

Search around for the schematic of the Bazz Fuss; it has an transformator in front of it (connect only one half of the trafo) to make the signal unbuffered

He credits on the schematic (or site) that he uses the technique from the AMZ pickup sim article, so if you cannot find the schematic, here is the link:

http://www.muzique.com/lab/pickups.htm

regards, Jack

[Paul Perry (Frostwave)]

Good one, Jack! wonder if that is the mystery passive impedance device that came up recently......