Booster with mid boost and treble&bass boost lodes?

[Kennt82]

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[Kennt82]

"Here's the gyrator, every 1/10th of the control's travel: As you can see, it only really does anything between 0-20% and 80-100%. The middle 60% is pretty subtle. "

Would a W-taper pot, like on Boss and old DOD pedals, work more evenly? I ask in general, not just to the topic project.

[Fancy Lime]

"Here's the gyrator, every 1/10th of the control's travel: As you can see, it only really does anything between 0-20% and 80-100%. The middle 60% is pretty subtle. "

Would a W-taper pot, like on Boss and old DOD pedals, work more evenly? I ask in general, not just to the topic project.

Yes it would. That is exactly the reason why they are used in these situations. It is also worth noting that the uneven pot response problem scales with total range. Meaning, if you only want to do ±9 db, it's not great but mostly fine. At ±15db it is already quite annoying. To me, ±12 db seems to be the absolute maximum range where gyrator EQs with linear pots are usable. Above that, W (or G or S) type are a must above that.

[antonis]

IMHO, +/- 12dB should be the upper/lower limit of anything system balancing..
(if more is needed, system is essentially inadequate and needs redesign..)

[Rob Strand]

IMHO, +/- 12dB should be the upper/lower limit of anything system balancing..
(if more is needed, system is essentially inadequate and needs redesign..)

What's often not realized with first-order equalizers is more dB can only be achieved by stretching the span of frequencies.  You either shift starting point or the ending point to make the hill higher.   There's no point going from 12dB to 18db if the difference is a boost 6dB between 10Hz and 20Hz.

This one moves the upper frequency of the bass (more or less) to get more boost but then it starts affecting the mids.




If you get 12dB boost from *two* 6dB boosts the slope is faster and the range of affected frequencies is more narrow.

[m4268588]

But, this may increase noise.

[Rob Strand]

You sometimes can get away with linear pots on gyrator circuits if you make the value of the pot 4 times (or less) the value of the feedback resistor.   (For the TS-9 values of pot = 20k and feedback R as 1k the ratio is 20:1 and you really need a G taper pot to prevent the control cramping at the ends.)

When compared to a larger pot value, the smaller pot value does affect the response to some degree.  You may need to tweak the gyrator values a bit to make the response similar to what it was before.   It depends what amount of boost you want to match them at as well.

[Fancy Lime]

IMHO, +/- 12dB should be the upper/lower limit of anything system balancing..
(if more is needed, system is essentially inadequate and needs redesign..)

+1

[ElectricDruid]

IMHO, +/- 12dB should be the upper/lower limit of anything system balancing..
(if more is needed, system is essentially inadequate and needs redesign..)

While this might be true for "system balancing" like in a hi-fi system where the original point of tone controls was supposed to be to help correct for room responses (lots of heavy curtains? Turn up the treble a touch) I don't think this is true for "tone shaping" applications at all. We're not trying to balance some existing response - we're creating one. For that job, we can make it as extreme as we like - although going crazy rarely leads to fantastic results in my experience.

This is fairly true for guitar pedals, although in that situation we do have some other tonal responses to consider (the guitar itself, the amp) but they are highly variable and unknown to the designer, so it's basically impossible to "design them in". Where it's even more true is for synth designs where you're creating sound from scratch and there's no previously-existing tonal response at all until you put it in.

So...depends what you're doing and why, I'd say.

[antonis]

We're not trying to balance some existing response - we're creating one.

So it is if you think so..

[Fancy Lime]

IMHO, +/- 12dB should be the upper/lower limit of anything system balancing..
(if more is needed, system is essentially inadequate and needs redesign..)

While this might be true for "system balancing" like in a hi-fi system where the original point of tone controls was supposed to be to help correct for room responses (lots of heavy curtains? Turn up the treble a touch) I don't think this is true for "tone shaping" applications at all. We're not trying to balance some existing response - we're creating one. For that job, we can make it as extreme as we like - although going crazy rarely leads to fantastic results in my experience.

This is fairly true for guitar pedals, although in that situation we do have some other tonal responses to consider (the guitar itself, the amp) but they are highly variable and unknown to the designer, so it's basically impossible to "design them in". Where it's even more true is for synth designs where you're creating sound from scratch and there's no previously-existing tonal response at all until you put it in.

So...depends what you're doing and why, I'd say.

+1 to that, too! However, I find that beyond 12db, controls with a standard pot get too coarse for most tone shaping applications. It's really more "tone remodeling" at that point. Also useful but a different application in my mind. If I want something more drastic than 12 db boost/cut, I like to add a 3-way switch to add or subtract another 24db. Total ±36 db with quite fine grained control should cover a lot of use cases.

[antonis]

I find that beyond 12db, controls with a standard pot get too coarse for most tone shaping applications. It's really more "tone remodeling" at that point.

That's partially what I was meaning..

But Tom took it into heart, viewing my comment as personal debasement regarding Hard Bargain..

[ElectricDruid]

I find that beyond 12db, controls with a standard pot get too coarse for most tone shaping applications. It's really more "tone remodeling" at that point.

That's partially what I was meaning..

But Tom took it into heart, viewing my comment as personal debasement regarding Hard Bargain..

Awww, no, Antonis, it's not personal and I didn't take it as such!

I think we basically all agree here, but perhaps we each have our own personal terminology?!? I like "Tone shaping becomes tone remodelling" though - very descriptive.

[antonis]

I think we basically all agree here,

Unfortunately, Yes..!!
(no room for a meaty spat..)

[ElectricDruid]

(no room for a meaty spat..)

LOL!! We should try harder!!

[Fancy Lime]

(no room for a meaty spat..)

LOL!! We should try harder!!

NEVER! ONLY WIMPS TRY HARDER!!!! AND COMMUNISTS!!!!!!!1!!!1!!¹11!!

Damn, I'm not good at this. Who would've thought that it could be this hard to start a senseless shouting match on the internet

[iainpunk]

on the topic of tone shaping with filters, i was doing some mid control experimentation a month ago, and came up with this circuit:



it boosts and cuts midrange inspired by the classic Swedish Chainsaw tone, but my own interpretation/weird version. i designed it and tinkered with it to have a perceived constant volume, while drastically changing the midrange character, this balancing of the perceived volume resulted in two different depths, and how 'fast' they react to the increased rotation of the pot (the boost lowers quicker than the cut). it cuts 16dB around 400-ish Hz, and boosts 27dB around 1100-ish Hz, but their overlapping bands make it less extreme as it may seem. best results with a anti-log pot, or a log pot in reverse.
its part of a very minimal-ish-t chainsaw inspired distortion.

I find that beyond 12db, controls with a standard pot get too coarse for most tone shaping applications. It's really more "tone remodeling" at that point.

i agree with this very much. this is one of the few ''common'' applications of a boost/cut way above 12dB. i would generally keep any band boosting under 6dB and any band stop under 9dB for most ''conventional'' sounding pedals.

cheers

edit: wrong image

[antonis]

on the topic of tone shaping with filters, i was doing some mid control experimentation a month ago, and came up with this circuit:

I presume it's designed for dual symmetrical supply, Iain..
Nevertheless, it should still need a bias resistor (path to GND), which should interact with 4.7 nF cap..

[iainpunk]

it was designed to tack onto a drive circuit without a coupling cap. its just a snippet of a circuit, a way to convey a basic idea without muddying it with the bias, coupling and power supply situation. kind of like how they do it in my textbooks from school, nice and uncluttered.

i'd think people would know by now that most of the time i put ideas out like that.

cheers

[antonis]

i'd think people would know by now that most of the time i put ideas out like that.

People would also know by know that you leave the all the dirty job to them..