looking for a clean blend for my fuzz face'ish pedal?

[foxfire]

i did a search or 2 but didn't see anything obvious or the link ended up being dead. i know this has been covered many times cause i remember ignoring the posts not knowing that most of the little circuits i was putting together were ff's. anyway i've used the buff'n blend but since i don't want a buffer on this i'm not sure were to go?

[Kornell]

If you don't want a buffer before splitting the signal you could try the minimal blender.

[foxfire]

obviously i had completely forgotten about the mini blend, thanks. i built the fet version, quick and simple. well it sure is noisy! i get signal but, it sounds liked like the fuzz was bleeding through so killed the fuzz. it wasn't the fuzz bleeding through. i've heard that fets are noisy but. if i weren't uing this with a fuzz it would be useless. now with a part count of 6 pieces i'm 99.9% sure my work is right. so where did i screw up?

[Gus]

Think about the input node of a FF type circuit (guitar to FF type).  What is it and how is it different than other input nodes like a TS...
If you understand that part then you can work out what you would need to do

[Barcode80]

the buff n blend is quiet as a mouse, and buffered, and in my layouts gallery

[Gus]

looked for the buff and blend found this link
http://www.geocities.com/jrtookmyfalseteeth/buffblnd.gif

Barcode80 did you try this with a stock FF?  A stock FF should act different after the SF than after just a guitar.

One could do a SIMPLE adding of one part to it for a stock FF type.  Hint in the 3tran circuit  and look around Jacks site for a inductor based  guitar sim.

[Barcode80]

no, a fuzz face should behave exactly as it usually does. the guitar is still hitting the fuzz face unbuffered, only the clean side is buffered. i can think of no logical reason it would act differently.

[foxfire]

i put together the ic mini blender using a 741. i still couldn't get it 100% even if i removed the output cap of the fuzz to kill it. so i thought how in the heck did i screw up the blender until i removed the input cap of the fuzz. with that gone i get a true clean. i haven't quite figured out what all this means yet though...

Think about the input node of a FF type circuit (guitar to FF type).  What is it and how is it different than other input nodes like a TS...
If you understand that part then you can work out what you would need to do

i'm not quite sure what you are hinting at but, i guess i'll have a comparative look at them. 

[Gus]

Look up inverting opamp circuits.  The first part of the ff can be thought of as the same circuit the Q2 emitter(think of it as a buffered Q1(collector)feedback R to Q1 base and the source R feeding the input node(the source R is the guitar)  A guitar is not a resistor but inductor(s) (pickups) resistors(pickup(s) and pots) and even has cap(s).  Q1  section of the ff type is part of what sets the touch control AND because it is part of the feedback of the first stage of the FF types there is an EQ from the RLC in the guitar

The opamp has high gain so the gain is close to the feedback R divided the series input R(Z)

The FF hfe Q1 selection is for Q1 openloop gain working with the closed loop feedback Rs(100k 47K etc divided by the guitar mess) for a more imperfect  closed loop first stage than an opamp inverting circuit. Q1 has way less gain than the opamp so the input node is not as close to being a perfect current summing node a perfect node would be 0 ohms at the - input of an opamp inverter. 

So one simple thing is to add a series resistor into a FF when it is driven by a low Z driver like a SF or EF Look at the 10k between the buffer and input of the distotion section of the 3 tran.  Jack's site has a better sim of the guitar.

Barcode80 did you try it or just post it should work?

[Barcode80]

admittedly, haven't tried it. i've used the bn'b for numerous fuzz blends, but not yet for a FF. i jut can't think of a logical reason it wouldn't work the same.