Tone knob Or not tone knob?

[owenjames]

Hi all,

I have just finished designing and making my new pedal. The Fuzzilla (pictures soon, atm its just the circuit). Its a standard fuzz, got a much different circuit topology to things like the Tonebender, Fuzz face and all those old school fuzzes. At the moment it just has fuzz and level controls. I really like the sound it makes, It basically has infinate sustain if you vibrato the string a little bit, and if you roll back the fuzz knob and guitar volume it gets almost completely clean.

But anyway my question is: Given I am going to be selling them, should I have a tone knob on it?

The circuit has a high cutoff at 6KHz into the fuzz section and one at about 1.5Khz out of the fuzz, to kill all off those horrible squarewave harmonics, It is a fairly standard 3dB/octave cut off so it doesn't kill all the treble when you set the gain low just softens the fuzz when you have high gain.

I could also just raise that cut off frequency and allow the player to cut the highs if need be using his/her amp tone controls.

If you suggest tone control what type should it be. A low pass filter with a freqency variable from 1.5KHz up would be the easiest, but would that suffice. I looked into the BMP tone control. Now I can mod that so it doesn't have that notch at 1KHz i wouldn't really want my pedal to have mid scoop, that just limits what you can do with it, woul dit be worth having that kind of tone control?

Thank you,

Ps check out my website for my previous creation the TriDrive.

[MikeH]

Looking at it from the side of the buyer, I'd say better to have a tone control and not need it, than to need a tone control and not have it.  Even if it's simply a low pass filter that most people will leave up all the time.  Sooner or later someone will want to darken up the sound; it's worth the extra $3 in parts.

[frequencycentral]

I personally think a tone control is essential. I really like the BM tone control, you can do a lot with it to tailor it to your needs by playing about with the values on Duncan's.

[CynicalMan]

I agree that its best to have a tone control but, if you're trying to market this as "vintage style" then leaving it out would be more convincing. If not, go for it!

[owenjames]

So you are all saying tone control.  What is best for fuzzes, something like the BMP that controlls bass and treble at the same time or somethign simpler?

[frequencycentral]

One observation I would make on the BM is that it imprints it's own character to whatever you graft it to. That may not be what you want. You should be able to engineer it to be a little more neutral. Maybe also try Mark Hammer's SWTC.

[Mark Hammer]

There is whether to have a control, and there is how to have a control.  

Some tone controls eat up a lot of signal, so if the design and intent of the pedal is to provide only modest output level, then some types of passive tone control might make it a wimpy pedal or necessitate enough of a design change to accommodate the tone control that it becomes a different pedal.

Alternatively, if the pedal has way more than enough output to pummel and amp's front end, then you have a certain amount of latitude to explore some passive tone-control options because there will be plenty of signal left over.

What is the typical anticipated context of use?  If someone is expected to throw this on top of an already dirty sound then it may well add so much treble and upper mids that it is annoying.  In which case a treble cut is needed to avoid rushing over to the amp every time you turn it on.

Then there is where you place any tone control.  In some of Joe Gagan's terrific designs, the bass rolloff is part of how the input to the clipping section is shaped.  In that roll it doesn't function as a make-it-sound-a-bit-smoother control but something that changes the character of the resulting distortion.  Finally, no reason why input-shaping and output shaping controls can't co-exist.

[Renegadrian]

I generally say NO to tone controls...there are some pedals that you just don't want anything that modifies its tone...
In the Valvecaster the tone just sucks, so the first thing to be done was getting rid of it...
At the other end, I really enjoyed the Fulltone Fat Boost Tone...

[jefe]

Generally speaking, I think people like knobs. The more knobs, the better. If I had to choose between a fuzz with 3 knobs, or a mere 2 knobs, I'd go for the 3 knober. Even though I'd probably just set the tone knob in one place and leave it there. 

Maybe offer it both ways? The "vintage" two knob, and the "delux" three knob.

[owenjames]

There is whether to have a control, and there is how to have a control.  

Some tone controls eat up a lot of signal, so if the design and intent of the pedal is to provide only modest output level, then some types of passive tone control might make it a wimpy pedal or necessitate enough of a design change to accommodate the tone control that it becomes a different pedal.

Alternatively, if the pedal has way more than enough output to pummel and amp's front end, then you have a certain amount of latitude to explore some passive tone-control options because there will be plenty of signal left over.

What is the typical anticipated context of use?  If someone is expected to throw this on top of an already dirty sound then it may well add so much treble and upper mids that it is annoying.  In which case a treble cut is needed to avoid rushing over to the amp every time you turn it on.

Then there is where you place any tone control.  In some of Joe Gagan's terrific designs, the bass rolloff is part of how the input to the clipping section is shaped.  In that roll it doesn't function as a make-it-sound-a-bit-smoother control but something that changes the character of the resulting distortion.  Finally, no reason why input-shaping and output shaping controls can't co-exist.

This pedal has about 40dB of gain so output is no problem.
I was planning on putting a tone control in the clipping stage (if you imagine where a fuzz face places its fuzz control, having a pot at the emitter of one of the transistors then having a cap attached to the variable leg of the pot.) I would do that but have the collector resistor as a pot with the leg connected to a cap that goes up to V+. As the gain of the common emmiter bjt amp is Rc/Re having the right cap value across a portion of Rc lowers the gain for those selected frequencies (selected by the position of the leg of Rc and the Cap value). What this does is when you roll down the tone control you are effectivly changing the cuttoff frequency of what gets amplified. so its kind of like an active filter.

I am doubting they would need anymore gain/dirt so i doubt they will be putting in a signal that loud or distorted, but you never know what guitarists might do.

I am not sure about input and output tone controlls, gettign to be too many knobs on one box, it is only 120X65mm. Which is best, input or output tone control? I presume output as lots of new harmonic content is generated by the clipping, is that a correct assumption? Also I have noticed that my guitar tone know does barely all to the sound when i put the gain at max. It does alot if you clean up the pedal a bit though so would an input tone knob be useful then?

[Mark Hammer]

Because the signal amplitude from wound strings is greater than that from unwound strings, allowing more bass content in the input signal increases the likelihood (and perceived amount) of distortion.  So, in some respects, that makes it very interactive with any gain/drive/fuzz control, and produces a broader range of possible tones.

At the other end, distortion IS added harmonic content, so there is always the question of whether the amount of harmonic content added when you step on the stompswitch is going to be a pleasant increase above what you had a moment ago, or a jarring and disruptive increase.  I can't emphasize enough here that you can go from super clean to seriously fuzzy without necessarily pushing the harmonic content past the point of tolerance.  Many overdrives, distortions, and fuzzes incorporate lowpass filtering so as to keep the the excess treble reined in. 

On the other hand, we all know that fuzz produced via a humbucker neck pickup is different than fuzz produced via a lipstick pickup or a dual-rails bridge pickup, so some means of tailoring the treble to allow less or more treble out helps to make a pedal manageable for more players.  If the pedal was just for you, then you could tailor the treble internally via component choices and be done with it.  But you say you want to sell it, so you need to plan for players who use rigs nothing at all like what YOU would use.  When factoring in the added control/s, sound business planning would suggest that you weigh the added production costs/effort against the differential likelihood that someone might buy it.  So, yeah 2 knobs is nice and cheap and simple and often "good enough", but if the pedal sits on the shelf without a buyer that elegance hasn't gotten you very far, has it?

Is 4 knobs "required"?  Not at all.  All some pedals want is one more control to taper off the top end.  The so-called SWTC (not my innovation at all, I just brought it to people's attention and touted its usefulness and simplicity) makes a really nice addition to a lot of 2 knobbers, and many folks here have done just that.  It's NOT an in-your-face sort of tone control like the BMP style, but is more suitable for dialing in "just right" treble content for just enough bite.

One way of accomplishing some interesting tonal adjustment but keeping knob-count manageable is to use a dual-ganged pot for tone, with one section used to alter bass content at input and the other for adjusting treble content at output or even for use within a BMP-style control.  So, let's say you had a small-plus-big input cap like Joe Gagan uses.  One half of a 100k dual-ganged pot could be used to dial in how much bass on the input.  In the meantime, the other half adjusts the treble/bass balance on the output.

Now, the BMP control normally adopts the strategy of splitting up the spectrum at a certain point, either with or without a bit of midscoop.  Check Jack Orman's AMZ site for some excellent info about this:  http://www.muzique.com/lab/tone3.htm   http://www.muzique.com/lab/dtone.htm    http://www.muzique.com/lab/atone.htm   So, what would happen if we moved the "crossover" point in the BM control up a bit, and wired up the second ganged section of the tone pot to reduce bass input as we turned the tone knob towards the bass side?  Think of it this way: with the post-fuzz tone control set for max treble, the fuzz would be hit with the most bass, getting the nastiest buzz possible, but with the post-fuzz tone set more towards the bass end, the top-end buzz would be removed/deaccentuated but the slighted-shifted crossover would let more lower mids through at the same time that the input bass would get progressively tamer.  In other words, this would achieve a warmer less "stressed" sound.  Points in between would get you a bunch of other variations.  three knobs and multiple personalities.  I like it!

[solderman]

Hi all,

IBut anyway my question is: Given I am going to be selling them, should I have a tone knob on it?

Hi
I think you might consider what you aim to accomplish with it. If its a standard passive treble roll off or something you want to shape what frequencies are distorted. why not a wet/dry pot to mix dist/not dist  Xx -to-Yy Hz and  with together with a filter pot to Set the limits for Xx and Yy Hz

//Solderman