That'll work. The one on the bottom. The circuit needs a simple gain stage and a pot to control it, then a tone stack.
Considering what it is and has under the cage, that's actually not so bad.
Instead, you could scrounge up some old vintage PA tube head, rewire the whole thing to get the two channels (with EQ, switching), but by the time you do all that I'm afraid saving maybe a $100 at the outset, it wont come out as pretty or perhaps even as functional.
The only reason to re-lace up some old vintage tube amp for guitar these days is for your own experience and education. Perhaps some pride in a job done well.
It certainly wouldnt be economical as a business - the vintage tube amplifier stock available to rework is all too expensive. Even if you could whip up some miraculous circuit, like the one above, you'd have to convince any customer (yourself in this case) that its more than a 1 trick pony - what with FLAMMAs floating about in the used market for < $100 - to trust their wallet to your craft.
@jjasniew said, "The only reason to re-lace up some old vintage tube amp for guitar these days is for your own experience and education. Perhaps some pride in a job done well."
That's what I had in mind. The Bulgara would simply be a test bed to start with, making DIY-ing easier and less expensive. I don't consider plugging in a cheap DSP modeler DIY. Right now, I'm using 3/4" plywood flat on the bench so there's something to stop the boards/components from moving around, and for easy access. The next step is an aluminum (or even wood) angle for all the pots and switches. And this if for basic operation. When everything gets mounted in a chassis, things may go from excellent to nightmare.
The context is Solid State, so I envisioned gutting the power section to make room for the SS power amp and another power supply--SMPS of course.
For learning and the possible discovery of some good, new concept, how about digitally controlling the analog signal? Personally, I don't see the need to model thousands of amp/speaker cabinet combinations to rotate through, unless you're part of a cover band. I just had a Johnson JM-250 on the bench. It is an early modelling amp notorious for its unreliability and extreme difficulty in repairing, so much so that few dared to take it on. I did find it quite amazing though, and the build quality was impressive. But it didn't sell and the company went defunct.
It's my opinion better to have a "Patton tank" and keep all the FX outside the box. When we get sick of something, or something better comes along, it's just a matter of bending down and unplugging/replugging. The old unit can then be sold, although for a loss, but at least we get something back.
That's what I had in mind. The Bulgara would simply be a test bed to start with, making DIY-ing easier and less expensive. I don't consider plugging in a cheap DSP modeler DIY. Right now, I'm using 3/4" plywood flat on the bench so there's something to stop the boards/components from moving around, and for easy access. The next step is an aluminum (or even wood) angle for all the pots and switches. And this if for basic operation. When everything gets mounted in a chassis, things may go from excellent to nightmare.
The context is Solid State, so I envisioned gutting the power section to make room for the SS power amp and another power supply--SMPS of course.
For learning and the possible discovery of some good, new concept, how about digitally controlling the analog signal? Personally, I don't see the need to model thousands of amp/speaker cabinet combinations to rotate through, unless you're part of a cover band. I just had a Johnson JM-250 on the bench. It is an early modelling amp notorious for its unreliability and extreme difficulty in repairing, so much so that few dared to take it on. I did find it quite amazing though, and the build quality was impressive. But it didn't sell and the company went defunct.
It's my opinion better to have a "Patton tank" and keep all the FX outside the box. When we get sick of something, or something better comes along, it's just a matter of bending down and unplugging/replugging. The old unit can then be sold, although for a loss, but at least we get something back.
The waveform looks exactly like a Fuzz Face but uses only one transistor. It will also be noisy.
Sounds like a "Tubelab" setup.
As many ways as there are petals on a flower. One of the myriad could be using model airplane servos mechanically connected to a potentiometer. That's closed loop position control that responds to a PWM value; give it 50% PWM, it goes to the halfway point in its rotation. I believe. The low torque ones are cheap, because everyone wants the high torque models. Given that they're probably not moving about a lot in a guitar amp, I'd expect reliability to be decent, say, compared to steering a model car.
Another unpopular one I've never seen anyone actually use is the old PWM over resistor trick. Imagine 100K with 10K in parallel, only with an (LED or Gate controlled) analog switch in series with the 10K. PWM 0%, you of course get 100K. PWM 100%, you get 9.1K. PWM somewhere in between 0 - 100%, you get a resistor somewhere in between 9.1 and 100k. As long as the PWM frequency is, say, 10X higher than any audio passing through you'd have a "digitally" controlled resistor value. Should not be too tough to generate PWM for guitar amplifier bandwidth, or ~100kHz.
I mention the PWM tack because I've seen the microprocessors these days with many I/O pins that are assignable to PWM output, whose PWM value sits in a register that you can easily program. Details like max frequency various uPs can do I know from nothing.
What to do for something "new", AFAIK? Get a circuit that makes a DC voltage proportional to how you're playing the guitar. Soft / loud is easiest and you can do soft/loud across a few frequency bands independently easily. (If you happen to have a Hex pickup, even easier) Have these signal values be read by a uP running some code, that then adjusts in real time all the servo connected mechanical potentiometers controlling your amp's paramaters. It'd be like having your own sound man continuously listening to your playing and adjusting the amplifier to sound how you like. Of course, there's a few steps between this dream and that reality, but why not auto-dynamic the whole amplifier tone? Compressor or auto-wah on steroids...the gain of every stage in the amp subtely goes up, as your last note decays.
I have too much fun thinking about any of this and no fun actually doing anything with it. You can do it; I hope it all works out somehow.
I got confused with the fuzz box. This one uses a single transistor. It's the "Russian" version of the Fetzer valve. I don't have the time or the desire to figure this out, but for tube distortion, it is common practice to use two stages; Hot and Cold bias is the lingo. The waveform supplied indicates a Fuzz Face kind of clipping; hard on top, soft on the bottom. It needs a buffer or the guitar pickups will be overloaded.
This looks like it should be quieter than the all transistor types because of the diodes, and the low resistor values.
This looks like it should be quieter than the all transistor types because of the diodes, and the low resistor values.
Sorry to have been unable to reply sooner. The demands of real life took over for a while.
Yes, the circuit looks as simple as a Fuzz-Face. But it sounds absolutely nothing like one!
To me, the sounds made by a Fuzz-Face are crude, nasty, and hideously unpleasant. If the sound of the Fuzz-Face was wiped from music history, I wouldn't be shedding any tears.
On the other hand, to my ears, the sound clip of Azevedo's "2BJTE" has a richer and better-sounding overdrive sound than any other solid-state analogue guitar amp I've heard, including many circuits that are much more complex. IMO, the sounds in the clip are not harsh, the texture is complex and varies with signal level, you can hear duty-cycle modulation going on, et cetera, et cetera. It's a really good overdriven guitar sound.
Of course one short recorded clip performed by a guitarist with limited skills and bad timing isn't much to go on. It could turn out that my early first impressions of the 2BJTE circuit are totally wrong, who knows.
For example, the clip doesn't really reveal how progressive the distorted sounds are. Do they go gradually from fully clean to fully distorted, like a great tube amp? Or do they jump straight from too-clean to fully distorted, with little transition in between? Or is there no clean at all, only full-on heavily distorted tones?
I have no idea.
But, FWIW, based on just that one short clip, I would say that there are many full-blown tube guitar amplifiers that sound less good than Azevedo's simple two-transistor circuit set to full-on "rawk" mode, as we hear it in that clip. 😱
Some years ago someone on diyAudio posted sound clips of a large, expensive, complex, tweaked and modified Marshall clone he'd built (it was a clone of some famous musicians Marshall that had been tweaked or modified by some agency known as SIR-something-or-the-other). The build was a labour of love, and the builder had obviously put lots of time, effort, blood, sweat, and tears into his very beautifully built amplifier.
For me it was an odd experienced to compare the sound clips of the $2000 hand-built Marshall clone, with the sound clips of Azevedo's fifty-cent, breadboarded-in-one-hour, two-transistor circuit. Played through headphones on my computer, both clips sounded very similar, except for minor differences in EQ!
As mentioned before, my first reaction to Azevedo's sound clip was that it is just too good to be true. I can't help but wonder if the Boss overdrive pedal Azevedo used between his guitar and his 2BJTE circuit was contributing some or most of that rich tone.
I have not built or verified that Azevedo's circuit really is capable of the sounds in that clip.
If it really does sound like that, I think it might be the sleeper of the last fify years of solid-state guitar amplifier design. More bang-for-the-buck than anything else I've ever seen or heard.
The additional head-scratcher is that the 2BJTE circuit completely dispenses with all the well-known mechanisms for creating acceptable-sounding distortion from an e-guitar using a SS circuit. No JFETs, no diodes, no carefully designed clipping circuits, no EQ, no low-pass filter, no high-pass filter. Just a couple of everyday transistors in a crude two-transistor DC coupled amplifier configuration.
From the engineering point of view, there are many design mistakes in the 2BJTE circuit, including useless components that don't do what they're supposed to do. But maybe they contribute to the distorted sound by accident, like Leo Fender's DC-coupled cathode follower. Or maybe they really do nothing at all. Someone has to build and try this thing out before we can know for sure. 🙂
-Gnobuddy
That's the one!
Yes, the circuit looks as simple as a Fuzz-Face. But it sounds absolutely nothing like one!
To me, the sounds made by a Fuzz-Face are crude, nasty, and hideously unpleasant. If the sound of the Fuzz-Face was wiped from music history, I wouldn't be shedding any tears.
On the other hand, to my ears, the sound clip of Azevedo's "2BJTE" has a richer and better-sounding overdrive sound than any other solid-state analogue guitar amp I've heard, including many circuits that are much more complex. IMO, the sounds in the clip are not harsh, the texture is complex and varies with signal level, you can hear duty-cycle modulation going on, et cetera, et cetera. It's a really good overdriven guitar sound.
Of course one short recorded clip performed by a guitarist with limited skills and bad timing isn't much to go on. It could turn out that my early first impressions of the 2BJTE circuit are totally wrong, who knows.
For example, the clip doesn't really reveal how progressive the distorted sounds are. Do they go gradually from fully clean to fully distorted, like a great tube amp? Or do they jump straight from too-clean to fully distorted, with little transition in between? Or is there no clean at all, only full-on heavily distorted tones?
I have no idea.
But, FWIW, based on just that one short clip, I would say that there are many full-blown tube guitar amplifiers that sound less good than Azevedo's simple two-transistor circuit set to full-on "rawk" mode, as we hear it in that clip. 😱
Some years ago someone on diyAudio posted sound clips of a large, expensive, complex, tweaked and modified Marshall clone he'd built (it was a clone of some famous musicians Marshall that had been tweaked or modified by some agency known as SIR-something-or-the-other). The build was a labour of love, and the builder had obviously put lots of time, effort, blood, sweat, and tears into his very beautifully built amplifier.
For me it was an odd experienced to compare the sound clips of the $2000 hand-built Marshall clone, with the sound clips of Azevedo's fifty-cent, breadboarded-in-one-hour, two-transistor circuit. Played through headphones on my computer, both clips sounded very similar, except for minor differences in EQ!
As mentioned before, my first reaction to Azevedo's sound clip was that it is just too good to be true. I can't help but wonder if the Boss overdrive pedal Azevedo used between his guitar and his 2BJTE circuit was contributing some or most of that rich tone.
I have not built or verified that Azevedo's circuit really is capable of the sounds in that clip.
If it really does sound like that, I think it might be the sleeper of the last fify years of solid-state guitar amplifier design. More bang-for-the-buck than anything else I've ever seen or heard.
The additional head-scratcher is that the 2BJTE circuit completely dispenses with all the well-known mechanisms for creating acceptable-sounding distortion from an e-guitar using a SS circuit. No JFETs, no diodes, no carefully designed clipping circuits, no EQ, no low-pass filter, no high-pass filter. Just a couple of everyday transistors in a crude two-transistor DC coupled amplifier configuration.
From the engineering point of view, there are many design mistakes in the 2BJTE circuit, including useless components that don't do what they're supposed to do. But maybe they contribute to the distorted sound by accident, like Leo Fender's DC-coupled cathode follower. Or maybe they really do nothing at all. Someone has to build and try this thing out before we can know for sure. 🙂
-Gnobuddy
One SPICE simulation, with a single steady-state sinewave input signal, at one single amplitude, reveals almost nothing about how an e-guitar circuit will sound.
A Fuzz-Face is like a face-tattoo. Hideous to most people, but a wonderful idea to a few. 😀
-Gnobuddy
Only your ears can decide if it's true for you. 🙂
Of course this also depends on the speaker(s) you play the FS06 through.
I've had good results with everything from headphones to computer speakers to small P.A. systems to an actual Boss Katana 50, set on its Acoustic channel, and with a simple signal attenuator inserted between the FS06 and the Katana, to keep from overdriving the Katana's own preamp.
I assume you've already found and listened to Brett Kingman's You Tube review of the Flamma Preamp? Kingman is Australian rock-guitar royalty, a top-notch studio / session musician as well as a "gun for hire" by some of the biggest performers in the country. He has the chops to demonstrate what the little FS06 Preamp is capable of.
We're getting into philosophical topics here, but my philosophy is that if lots of other people want something badly, then it will be overpriced, and therefore I avoid that thing.
Instead, I find an alternative. Most of the time, you can find an alternative that is just as good or better, but far less popular, and therefore, far less overpriced.
In our insanely consumerist society, the price you pay for a thing does not reflect its value or quality. It only reflects what advertisers have managed to convince people that it's worth.
This manipulation of people's assessments has been going on for decades. In the 1980s, as the Yuppie consumerist culture took over from a more considered and thoughtful earlier American viewpoint, sociologists did an experiment in which they cut cheeses in half, marked up prices on one half, and put both halves back on supermarket shelves (with permission!).
The sociologists found that the majority of people had already been brainwashed to believe "You get what you pay for", and therefore, blindly picked out and preferred the more expensive cheese-halves, thinking they were superior to the lower-priced halves, when in fact, they were identical.
Agreed.
Today on Amazon.com, you can find the Flamma Preamp for $60.79 USD: ( https://www.amazon.com/FLAMMA-Digit...e/dp/B08LMLRQ44/ref=sr_1_5?crid=2KUGBIVUNCZI5 )
If you simply painted the logo of a "boutique" FX pedal manufacturer on the pedal, it would immediately be worth $350 USD instead of $61.
If you painted an Apple logo on an FS06, and put it in an Apple store, it would immediately be worth $500 USD instead of $350 USD.
To be clear: I have no affiliation whatsoever with Flamma Innovations.
-Gnobuddy
Had a listen, and yes to my ears it's a good classic overdrive sound. I have played though a couple of modern styled Marshall tube amps that sounded ice picky and harsh distortion..This sounds more like a vintage style, smoother and you can still discern individual notes of the chords. It would probably pair up nicely with a cleanish Jfet boost in front giving the higher impedance input, adding a volume control etc.. good stuff.
That's what I think, too. To me it sounds kinda like a well-recorded classic Marshall amp, after the recording engineer's worked a little magic to remove some of the spikier and harsher treble frequencies.
Now, how in the world can a couple of fifty-cent transistors manage to sound like a big box full of Marshally goodness that costs several grand?
I think Western culture's taste for harsh timbres has been gradually increasing for a very long time - many centuries. I think the process accelerated dramatically in the second half of the twentieth century, though it began centuries earlier than that.
In the English church, several centuries ago in the era of plainsong, octave harmony became the only acceptable polyphony. Before that, even perfect octaves were too harsh; only monophony was acceptable to the Church.
It took a long time before a perfect fifth (very, very slightly harsher than an octave) became acceptable in addition to the octave.
Another long period before major and minor thirds became acceptable. Before that, thirds were considered too harsh.
Fast-forward a few centuries to Les Paul (the musician) and his squeaky-clean electric guitar sound on hits like 1951's "Mocking Bird Hill":
In that song, Lester Polsfuss' (Les Paul's real name) guitar sounds so clean and bright it sounds more like an imaginary steel-stringed harp than a sound we would identify as electric guitar today. Almost a music-box tinkle, even for the guitar solo (with lots of Les Paul's trademark slapback echo slathered on.)
After Les Paul, the electric blues-guitar greats came along and added perceptible amounts of low-order distortion to their music. We got what we now think of as classic blues guitar tones.
After that came Jim Marshall's box of grit, a weapon well deployed by Jeff Beck, Jimi Hendrix, Eric Clapton, Robin Trower, et al. These guys sounded so harsh that while teenagers loved their stuff, their parents were aghast.
After "classic rock" we had things like Deep Purple, which evolved into Metal, which itself fragmented into a whole slew of ever-harsher derivatives.
By the 1990s and early 2000s there were music genres that sound so harsh to me that I find them unbearable to listen too. To my ears, the guitars in some of these bands sound more like power tools grinding on the proverbial tin roof than like guitars. Les Paul's 1950 steel-harp sounds are a universe away.
I think this is why newer Marshall amplifier designs sound harsher and brighter than vintage ones. They are made for a different generation of ears, ears that want a lot more harshness than the ears of old fogies like us. These younger ears grew up listening to guitar sounds like the ones in the group Evanescence, rather than the guitar sounds of Cream or The Rolling Stones or Santana.
My thoughts exactly.
If the sound clip really did come from this 2BJTE circuit, I also think the circuit is ripe for some further tweaking.
Look, for example, at the values of R2/C2. Both components appear to do nothing whatsoever. R2 is too small to affect the DC operating point of T1, and C2 is too small to bypass it at audio frequencies.
Or look at the values of R7 and C3. The second BC109 is running at quite a high current. Is this really necessary for it to sound right? If not, it would be interesting to scale down operating currents and scale up resistor values, to reduce power consumption in case someone wants to run this off the usual 9V flat battery.
Even the ratio of R4 and R1 is curious. If R4 were a bigger value, C3 wouldn't need to be so huge. (But would it still sound the same? I don't know, because I still don't understand why this circuit sounds the way it allegedly sounds in that MP3 clip Azevedo posted.)
There's also the striking fact that there is no EQ curve built into the circuit at all, other than the accidental one resulting from the effect of the bootstrap components C3/R4 at lower frequencies. Would it sound better with some of the usual EQ tricks, in particular, removing some of the deeper bass frequencies before applying the signal to T1?
-Gnobuddy
Attachments
Well, what I've found is you read what people say about stuff. If the person is the type who's honest and speaks in a believable way, i.e. authentic, you can trust in the probability of what they say being true. It helps to know such person has a valid background in the context of which they speak. Example, I bought my Lii Audio F15s because of what certain people with experience in the context of such things said about how they sounded and I coundnt see any reason not to believe them.
Walmart has this FLAMMA device currently on sale for $60 USD, free shipping. I just sold a few random ShopSmith parts that had been lying around for years, for $50 on ebay. My FS06 will arrive by Dec 3rd, according to Walmart. They also mention free returns, until Jan 31st. That should give me enough time to confirm any truth - as in Jeff Beck Truth - to my ears. As if I could play anything like him...
Thanks, Gnobuddy! Perhaps I'll hang my DIY guitar amp design / build hat with this one too.
Earlier in this thread, I mentioned a British company that made a guitar amplifier consisting of an all-valve preamplifier, feeding into a massively powerful solid-state class D power amplifier.
I had forgotten the manufacturer and model name, and couldn't locate that video on the Anderton's Music You Tube channel, where I first saw it.
I finally found the manufacturer: a British company known as Matrix Amplification.
Here is the manufacturer's product page for their VB800 hybrid amplifier: https://usa.matrixamplification.com/guitar-amps.html?___SID=U
It's listed as "Out of stock". The now-usual supply chain woes, or did the product get axed because it didn't sell well enough? I have no idea.
Matrix Amplification also makes massively powerful 1U and 2U rack-mountable class D power amplifiers for use by guitarists with their Axe FXs and Kempers and Quad Cortexes.
-Gnobuddy
I had forgotten the manufacturer and model name, and couldn't locate that video on the Anderton's Music You Tube channel, where I first saw it.
I finally found the manufacturer: a British company known as Matrix Amplification.
Here is the manufacturer's product page for their VB800 hybrid amplifier: https://usa.matrixamplification.com/guitar-amps.html?___SID=U
It's listed as "Out of stock". The now-usual supply chain woes, or did the product get axed because it didn't sell well enough? I have no idea.
Matrix Amplification also makes massively powerful 1U and 2U rack-mountable class D power amplifiers for use by guitarists with their Axe FXs and Kempers and Quad Cortexes.
-Gnobuddy
Wow. The deal of the decade, from my perspective!
Thank you for the implied confidence in my posts. When I post, I do try to make it clear whether I'm stating a personal opinion, or an actual fact. Obviously my fondness for the Flamma Preamp is in the former category.
I have spent literally years building and trying out multiple tube and solid-stage guitar amplifiers, so it would be reasonable to think I'd be biased towards one of my own creations. But no, I think the Flamma Preamp has completely outclassed everything I've ever come up with myself. 😳
I hope you find you enjoy your Preamp as much as I enjoy mine! 🙂
I have two of these, now. One sits on a side table in the living-room, next to the beater guitar, for instant guitar noodling.
The second one is packed into a little box with a few FX pedals that I carry to our weekly jams. It's also a back-up if Flamma Innovations disappears just as quickly as they appeared, and all their pedals disappear too. (So many oddly-named Chinese FX pedal manufacturers seem to come and go within months. Only their You Tube reviews and demos remain.)
My personal favourite two amp models in this little purple box are #1 (a Blues Deluxe) set to its clean channel, and #3 (a Two Rock Coral) set to its drive channel. To my ears, the Fender model in the $60 Preamp sounds better than any of the actual Fender modelling amplifiers, including the budget Mustang Micro, and the very expensive Tone Master amps. The Tone Masters seem to totally lose it every now and then, sounding utterly and unpleasantly solid-state for a split second as though the modelling mask fell away for a moment, revealing the naked solid-state sound underneath.
I've never seen or heard and actual Two Rock Coral, so I have no idea how the Flamma model compares. But what I can say is that the Coral model sounds very good to me, is extremely progressive and touch-sensitive if you're conservative with the gain knob, and does a beautiful job of "just on the edge of overdrive" tones, moving between clean and overdriven based on your picking force. This is exactly the thing that most solid-state guitar amps famously fail at, so I was very impressed.
I've found the Flamma Preamp works well with pedals, too. I've tried it with an EHX Soul Food in front of it, and various reverb and delay pedals after it, as well as a Digitech SDrum, a Digitech Trio+, and a Flamma drum/looper pedal. The Preamp got along with all of them, though I ended up using a DIY pot-in-a-little-box to reduce the Preamp output level before feeding it into the Flamma drum/looper pedal, for better gain staging.
-Gnobuddy
I am wondering if this is an example of a circuit "behaving somewhat badly" which for electric guitar sounds surprisingly good! The first stage emitter resistor and "bypass" cap as you mentioned..R2 might as well be zero, but having something in the order of 100 ohms would introduce some degenerative local feedback, maybe to make the operating point more stable. But C2? Luckily it's a straightforward build on a solderless breadboard, and it might be very interesting to tinker with.
Well, I just did a first test run of the circuit. It sounds pretty impressive for a two transistor minimalist design, but I don't feel (yet) it is the holy grail of overdrive. The first thing that came to my mind is that it sounds like a tube screamer, but a bit harsher on high frequencies. I ran it in a simulator first, and indeed the top of the waveform has rather sharp edges..
The setup was a clean jfet stage with a direct coupled emitter follower, to have a low enough impedance, into a 100k pot and then the 2BJTE circuit. The output then goes through a 'master volume' pot and a big muff style tone control, and then a transistor power amp with a celestion eight-fifteen speaker. So very simple gear.
It is a circuit worth fooling around with I think, you do get a lot of tone for only two transistors... recommended for tinkering!
The setup was a clean jfet stage with a direct coupled emitter follower, to have a low enough impedance, into a 100k pot and then the 2BJTE circuit. The output then goes through a 'master volume' pot and a big muff style tone control, and then a transistor power amp with a celestion eight-fifteen speaker. So very simple gear.
It is a circuit worth fooling around with I think, you do get a lot of tone for only two transistors... recommended for tinkering!
One observation is that for most normal amplification stages, a designer will try to make design choices which follow certain standards of good stability, linear operation, minimal distortion etc. Most of the time when these criteria are met, one "assumes" the circuit to be operating within normal constraints. So for example how small does a signal have to be, in order to for us to consider the amplifier to be operating as a small-signal amplifier with the normal calculations and rules applying to said amplifier stage? According to my college text book, a signal is considered "small" if the peak to peak swing in emitter current is less than 10% of the quiescent emitter current (Ie). For larger signal swings you start to see the effects of compression on the sine negative half cycle and elongation of the positive half cycle (progressive increase in distortion). This is due to the non-linearity of the diode curve of the BJT. R2 is lower than what we would see in a "normal" CE amplifier, and I suspect that increasing it up past 100 ohms, say 500 to 1 K ohm would reduce the signal at the emitter to a point where the peak to peak current swing would get below 10% of quiescent Ie and it would behave "nicely". Reducing R2 down to zero may have the effect of sounding more fuzz-like. I still don't get why C2 is there exactly.