Maybe stupid question concerning fuzzface, buffers impedance, etc.

Started by CodeMonk, April 29, 2015, 04:48:15 AM

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CodeMonk

The "so called conventional wisdom" has said for ages that having a buffered pedal before a fuzz face (and tone bender I assume). is not a good thing.
The reason being from what I have read is that those effects expect the pickups, with high impedance to be feeding it, while a buffered effect has a low output impedance, affecting the sound in a sometimes negative way (Yeah I know, personal preference and all that can negate all that).
Also this page on muzique.com ( http://www.muzique.com/news/buffers-before-fuzz/ ) kinda poo poos that "theory" or myth.
To my own ears, my various fuzzes that I ran after my wah made my way sound better after I added an output buffer (Taken from the Clyde) to my wah.
(Doesn't really apply to my main point here, just thought I would mention it).

Now for several questions, thoughts, random mussing, and blathering idiocy...
1. Low Impedance signal going into a FF : Bad?
2. High Impedance signal going into a FF : Good?
3. The Big Cheese (Courtesy of RG and Lovetone) which has op amp input and output buffers is supposed to sound awesome. Due to far more than the buffers I'm sure.
3b. Is the output impedance of the Big cheese input buffer high or low, or middle of the road, or unicorn tears?
4. Note on the Bazz Fuss Deluxe reads "42TM018 transformer is not required if NO buffered effects preceed this circuit" for pickup simulation. ( http://home-wrecker.com/bazz.html )

This gives rise to a few thoughts/ideas/solutions (whether needed or warranted or a waste of time space, resources, brain cells, etc.) regarding the Fuzz Face/ Tonebender and buffer/impedance issues...
1, Stick the Big Cheese buffer in the Fuzz Face/Tonebender box.
2. Stick the 42TM018 transformer into the Fuzz Face/Tonebender box.
3. Do something else. Like a Rum and Coke and forget about all this crap? (Or all of the above?)

Any thoughts, solutions (if needed), comments, insults, donations to the *Codemonk Foundation™, are appreciated.





*Fictional institution but still accepts donations of donuts, rootbeer and pizza.

Gus

If you search this forum you might find good information about what is going on in a FF like circuit.  The feedback/ first transistor bias resistor and Q1 used is important

BG is not a FF circuit there is a difference (not the opamps)

Output resistance can be calculated for the BG

Do the math or run a sim or build the circuits and measure/test would be a good way to learn.  There is a difference with a buffer and the first stage of a 3 transistor tone bender like circuit (the input stage of the hot Si gain and output resistance was adjusted for the gain stage after it)




CodeMonk

Quote from: Gus on April 29, 2015, 05:17:03 AM
If you search this forum you might find good information about what is going on in a FF like circuit.  The feedback/ first transistor bias resistor and Q1 used is important

BG is not a FF circuit there is a difference (not the opamps)

Output resistance can be calculated for the BG

Do the math or run a sim or build the circuits and measure/test would be a good way to learn.  There is a difference with a buffer and the first stage of a 3 transistor tone bender like circuit (the input stage of the hot Si gain and output resistance was adjusted for the gain stage after it)

Got my cheeses mixed up.
I think maybe this post, right or wrong, kinda confuzzled me a bit me ( http://www.diystompboxes.com/smfforum/index.php?topic=45791.msg335822#msg335822 ) plus a few other posts here alluding to some similarities or concepts between the two circuits to some, even if to a small, degree.
I do realize they are VERY different circuits.

My main point for this thread was:
QuoteThe "so called conventional wisdom" has said for ages that having a buffered pedal before a fuzz face (and tone bender I assume). is not a good thing.

And could these ideas be part of a solution.
QuoteThis gives rise to a few thoughts/ideas/solutions (whether needed or warranted or a waste of time space, resources, brain cells, etc.) regarding the Fuzz Face/ Tonebender and buffer/impedance issues...
1, Stick the Big Cheese buffer in the Fuzz Face/Tonebender box.
2. Stick the 42TM018 transformer into the Fuzz Face/Tonebender box.
3. Do something else. Like a Rum and Coke and forget about all this crap? (Or all of the above?)
#2 is what really piqued my interest.

Another primary point is getting the FF to play nice with buffered pedals and if anyone here has gone down that path for better or worse.

I'm not looking for any hand holding here, just the personal experiences of others that have worked on this and what resources they may have used to accomplish their respective tasks (Links. books, other circuits, what have you).
I'm the type that occasionally likes to reinvent the wheel.
I also prefer to learn things the hard way. By reading loads of info, trail and error, etc.
I personally think that a lesson learned the hard way is a lesson remembered better.
If you've noticed any of my posts here, I don't often ask for help. Thats one of my biggest flaws, I have trouble asking for help, regardless of the task.
To me, its far more rewarding to learn something when you have to bust your ass to learn it than being spoon fed the info.

Sorry if I came across as someone looking for the easy way out.


And this is definitely on my to do list (As well a some more reading after I get a few other tasks that I am way, way behind on):
QuoteDo the math or run a sim or build the circuits and measure/test


Edit:
BTW, this is a project/idea that I am still several weeks away from even starting.

induction

You may find this interesting.

I've had good experience with the AMZ pickup simulator, which is similar to your item #2, but I prefer to use it only when necessary (fuzz after wah, for example). It makes the fuzz face sound nice, but it changes the way it cleans up with the volume knob. Hardwiring it into the fuzz face circuit isn't a bad idea, but I'd want to keep the option of turning it off. I'd also want to include the input buffer before the transformer/pickup sim, because the wah into fuzz trick doesn't work with just the pickup sim, it needs the buffer.

But aquataur and Gus know way more about this than me, so add a few grains of salt wherever you see fit.

CodeMonk

Quote from: induction on April 29, 2015, 06:34:20 AM
You may find this interesting.

I've had good experience with the AMZ pickup simulator, which is similar to your item #2, but I prefer to use it only when necessary (fuzz after wah, for example). It makes the fuzz face sound nice, but it changes the way it cleans up with the volume knob. Hardwiring it into the fuzz face circuit isn't a bad idea, but I'd want to keep the option of turning it off. I'd also want to include the input buffer before the transformer/pickup sim, because the wah into fuzz trick doesn't work with just the pickup sim, it needs the buffer.

But aquataur and Gus know way more about this than me, so add a few grains of salt wherever you see fit.

That was very very interesting.
The nomenclature and writing style he used was a little unconventional compared to what I seem to see more often, but I've got a method of reading for that *.
I'm the type of person that while a passenger on a long trip, I tend to read technical books/documents (Except when I read Stephen King's The Langoliers while on a flight to mexico for xmas vacation a few years ago :) My GF thought I was a nuts for that )

And I almost always add those grains of salt.
I often learn best by reading several articles to accomplish the same thing via different means and pick and choose bits and pieces from each one to build my own solution.
That method has served me VERY well over the years.

* This works VERY well for me and maybe it will help others.
Pick part of the technical aspect of the text that you understand 100%
Read it 3 or 4 times, but pay more attention to HOW THEY SAY it instead of what they say. It makes reading and understanding the rest of it A LOT EASIER.

garcho

QuoteStick the 42TM018 transformer into the Fuzz Face/Tonebender box.

That's worked on a few pedals for me.
  • SUPPORTER
"...and weird on top!"

Gus

induction
I looked at the poker face link and that had a link to fuzz central axis fuzz.  Have you seen this schematic?

This was first on the web at effectronics Note the 10K 100 ohm resistors at the first stage, the placement of the bias control and RC filter

CodeMonk you can try a 4.7K or 10K etc. series resistor before the input of the FF like circuit.  IIRC the Fulltone 69 fuzz has a variable resistor input.

The FF has the inverting feedback and so does the BMP input (C to B resistor, however the interaction is reduced because of the input series resistor) Look for how the input stage is biased.
Looking at how the input configured can give a hint to the interactions it will have with what is before it.

CodeMonk

Thats an intriguing idea there.
Will definitely give it a shot.


Thanks.