Dunlop - JBF-3 Joe Bonamassa Fuzz Face [schematic]
- Xplorer
- Solder Soldier
looking at he tycobrahe schematic : am i right if i say that for an "octaved" basic fuzz it's as simple as adding the doubling octave circuit ( with the transformer and the two diodes ) , just between the 0,01 uf cap and the 500k volume pot, on a simple fuzz circuit or am i wrong ? cause i think that the smooth and rich personality of the joe bonamassa's germanium fuzz is a good candidate as a base for an octavia, i wanna hear it. the fuzz alone, of a tycobrahe ( through the different videos on youtube of some clones ) is really a fuzz that i don't like ...
- Seiche
- Old Solderhand
So i tried it with the normal 500kA volume control and compared to the 100kA i had in there before (forgot to mention) it is much too dark. Basically the stock version of this circuit is almost unusable for me, don't get why Joe would like such a low volume and dark fuzz, not really "tuned for HBs" at all imho. Only advantage of a 500kA is a rangemaster after the fuzz works better, but that can be remedied with a higher input cap on the rangemaster anyway.Seiche wrote:so i finished mine today. YAFF right? but i gave my other ge ff to my friend for his b-day and started to really miss it. I really like the two trimmers.
i went with a 1k instead of the 332 ohm resistor, because it didn't have enough volume imho (i like to have some extra volume just in case. i guess joe can get away with it using multiple amps and effects loops etc.). I ended up using 1T308Bs for both Q1 and Q2 (Hfe 86 and 91) because they have very low leakage (i guess b/c they are military spec?) and sound great. I also left out the 10ohm res.
The stock JBF-3 is supposed to really "shine" (TGP speak) when boosting a cooking amp, which i didn't get the chance to try yet.
All in all the I like Axis Fuzz of FuzzCentral much better for what I want. Maybe I'm a silicon-guy, though
- Xplorer
- Solder Soldier
yeah, it can be dark. it depends of what settings you're using, in the chain.
a 100ka volume pot would change this according to you ?
probably a different cap value, maybe lower, would be fine ? anyway i have an echoplex ep3 preamp after the fuzz/octavia on my project, and it can add some boost, some clarity, some control on the overal gain and noises when the fuzz knob is cranked.
mine sounds a lot like this one :
the recording isn't good but the performance and what you can imagine through this is incredible, to me.
( but not as trebly as the studio version of are you experienced )
yes, i'd think of this fuzz like a bit dark, and that's what i was looking for. now, it's a bit the same as jeff beck's use of the treble knob completely turned to 0, but getting some higher frequencys back , with a cranked amp.
a 100ka volume pot would change this according to you ?
probably a different cap value, maybe lower, would be fine ? anyway i have an echoplex ep3 preamp after the fuzz/octavia on my project, and it can add some boost, some clarity, some control on the overal gain and noises when the fuzz knob is cranked.
mine sounds a lot like this one :
the recording isn't good but the performance and what you can imagine through this is incredible, to me.
( but not as trebly as the studio version of are you experienced )
yes, i'd think of this fuzz like a bit dark, and that's what i was looking for. now, it's a bit the same as jeff beck's use of the treble knob completely turned to 0, but getting some higher frequencys back , with a cranked amp.
- Seiche
- Old Solderhand
yes the 100kA definitely changes that. gets rid of the overall darkness (which is kind of like a "blanket"). Apparently that is also the value that Eric Johnson prefers. I only heard about that trick in "the technology of the FF" and other online sources.Xplorer wrote:yeah, it can be dark. it depends of what settings you're using, in the chain.
a 100ka volume pot would change this according to you ?
probably a different cap value, maybe lower, would be fine ?
Different cap value maybe, but that might also thin out the sound?
- Xplorer
- Solder Soldier
i'll try it. thanks. yeah, i don't know the tech of the FF article by heart yet
do you remember where you discovered that it's eric johnson's favourite value ? interesting.
i love his version :
does it sound more like this ?
do you remember where you discovered that it's eric johnson's favourite value ? interesting.
i love his version :
does it sound more like this ?
- Seiche
- Old Solderhand
- Xplorer
- Solder Soldier
yes, since i've seen that on the tech of the FF article. i didn't know that and i'll try it, thanks.
i'm thinking of this : why not having a 100k pot and a switch for a 400k resistor or a 400 - 500k pot which would act as a clarity controler ? i mean : switching or blending the highs or darkness ? what do you think ?
i'm thinking of this : why not having a 100k pot and a switch for a 400k resistor or a 400 - 500k pot which would act as a clarity controler ? i mean : switching or blending the highs or darkness ? what do you think ?
- Xplorer
- Solder Soldier
and ... something i don't understand, maybe it's a stupid question but i could perhaps endly discover what it means : why would that be different to have a pot that is a 100k resistor, compared to a 500k pot that is set at (1/5 up)
100k of resistance ? and when both are all the way up, it means that they have zero resistance on the output, whatever pot value they are when they're rolled down, right ? so how is it different ?
100k of resistance ? and when both are all the way up, it means that they have zero resistance on the output, whatever pot value they are when they're rolled down, right ? so how is it different ?
- Seiche
- Old Solderhand
it's because the pot forms a voltage divider like this:Xplorer wrote:and ... something i don't understand, maybe it's a stupid question but i could perhaps endly discover what it means : why would that be different to have a pot that is a 100k resistor, compared to a 500k pot that is set at (1/5 up)
100k of resistance ? and when both are all the way up, it means that they have zero resistance on the output, whatever pot value they are when they're rolled down, right ? so how is it different ?
now if you put the values of a 500k pot, compared to a 100k pot set at the same setting (1/5 up, or 4/5 up) in this formula:
you'll understand.
- Xplorer
- Solder Soldier
Actualy now, i start again to not understand where is the difference.it's because the pot forms a voltage divider like this:
now if you put the values of a 500k pot, compared to a 100k pot set at the same setting (1/5 up, or 4/5 up) in this formula:
you'll understand.
because with this formula, if we compare the 100k and the 500k at half way up for example ( with Vin = 9v ) :
Vout = 50/(50+50) x 9 = 4,5
Vout = 250/(250+250) x 9 = 4,5
so .. why is it different to have a 100k pot instead of a 500k ?
- Bernardduur
- Transistor Tuner
High pass filter
'No more....... loud music.......'
Follow my love for pedals and amps on https://bernardduur.blogspot.com and https://www.instagram.com/bernardduur1
Follow my love for pedals and amps on https://bernardduur.blogspot.com and https://www.instagram.com/bernardduur1
- Seiche
- Old Solderhand
that's right. the voltage divider explained above is the reason why a smaller pot has the same volume on all settings. But the output cap forms a high pass filter with the volume pot.Bernardduur wrote:High pass filter
The higher R gets, the lower the cutoff frequency is, passing less high frequencies leading to a darker sound.
- Xplorer
- Solder Soldier
ok.
so the 0,01 uf is C , and acts on the high pass, into this phenomen, with the pot and the ground. but i'm not sure to understand how i can find back what is what in this schematic, compared to the previous one with the pot.
on this one, R is going at this point where C and Vout are connected, and at the other point, is it the ground ?
so the 0,01 uf is C , and acts on the high pass, into this phenomen, with the pot and the ground. but i'm not sure to understand how i can find back what is what in this schematic, compared to the previous one with the pot.
on this one, R is going at this point where C and Vout are connected, and at the other point, is it the ground ?
- Xplorer
- Solder Soldier
guys, thanks for this important lesson.
i tried with a 100k lin as i didn't have a log, and i replaced the 1k by a 2k pot for the fuzz.
indeed, it's a lot brighter.
bu there are still some things i like when it's a 500ka pot. so is it right if i still use the 100k pot as a volume, but if i add a pot wired as a variable 500k resistor, between the two lugs of the 100k that define Z 2 ? ( second lug and the ground lug )
so i would have both worlds, and i could adjust the frequencys, from the previous 500k volume with its darker tonal character, to the simple brighter 100k volume pot used in this version, when the 500k pot has zero resistance. is it right ?
i tried with a 100k lin as i didn't have a log, and i replaced the 1k by a 2k pot for the fuzz.
indeed, it's a lot brighter.
bu there are still some things i like when it's a 500ka pot. so is it right if i still use the 100k pot as a volume, but if i add a pot wired as a variable 500k resistor, between the two lugs of the 100k that define Z 2 ? ( second lug and the ground lug )
so i would have both worlds, and i could adjust the frequencys, from the previous 500k volume with its darker tonal character, to the simple brighter 100k volume pot used in this version, when the 500k pot has zero resistance. is it right ?
- Xplorer
- Solder Soldier
but yes, thinking of this, if for example with the 100k pot set on max for max volume, and the 500k "tone" pot set on max for a dark sound, Vout = ( 500/(500+0) )x 9 = 9v , and some darker frequencys.
now , with the 500k pot set on zero, and the 100k volume pot set on max volume i'd still have
Vout = ( 100/(100+0) ) x9 = 9v and some brighter frequencys.
but if i set the 500k pot at max, and the volume pot at half way, the 500k pot would have an efect on the voltage division : Vout = ( (500+50) / ((500+50)+50) ) x 9 = ( 550 / 600 ) x 9 = 8,25v, much over 4,5v though the "real" volume pot ( 100k ) is set at half way..
i wonder how to do to avoid the effect of the dark/bright 500k pot on the voltage division, the volume.
now , with the 500k pot set on zero, and the 100k volume pot set on max volume i'd still have
Vout = ( 100/(100+0) ) x9 = 9v and some brighter frequencys.
but if i set the 500k pot at max, and the volume pot at half way, the 500k pot would have an efect on the voltage division : Vout = ( (500+50) / ((500+50)+50) ) x 9 = ( 550 / 600 ) x 9 = 8,25v, much over 4,5v though the "real" volume pot ( 100k ) is set at half way..
i wonder how to do to avoid the effect of the dark/bright 500k pot on the voltage division, the volume.
- Seiche
- Old Solderhand
be careful how ohms law works, parallel resistors don't add up, that's resistors in series.
how about a switchable resistor in parallel to the 500k, giving you about 100k when the switch is closed (like a 130k? correct me if I'm wrong). letting you switch back and forth from 100k to 500k.
i know Analogman uses a 250kA pot for the Sunface, as an in-between-choice.
how about a switchable resistor in parallel to the 500k, giving you about 100k when the switch is closed (like a 130k? correct me if I'm wrong). letting you switch back and forth from 100k to 500k.
i know Analogman uses a 250kA pot for the Sunface, as an in-between-choice.
- Xplorer
- Solder Soldier
yes, very nice tech site about pots. i'll read it.
yeah, i realise that i was wrong, as the 100k pot and the 500k pot wouldn't be synchronised when turning.
but this resistor in parrallel could perhaps be replaced by a pot instead of using a swith ? and it would be much more simple than my previous wrong idea !
yeah, i realise that i was wrong, as the 100k pot and the 500k pot wouldn't be synchronised when turning.
but this resistor in parrallel could perhaps be replaced by a pot instead of using a swith ? and it would be much more simple than my previous wrong idea !