How to have a natural and flat response on FX?

[Phorhas]

Iwas wondering, how do we control the EQ so that when the knob are all turned down the respone would flat with no scooping or boosting ?

It's maybe a silly question I know (I'm just starting) but I have played on a many differant amps and FX boxes and I knoe that a flat response isn't  that frequent...

Thnx,
Dan
:roll:

[ExpAnonColin]

I assume you're talking about the logarithmic pots versus straight-line (can't think of the rigght word) pots.  There are two different kinds, there's even audio taper to make it harder.  If you took algebra, you should know that a logarithmic graph starts really slowly and then all of a sudden curves up and goes just about straight up while a straight graph is just a ramp.  I think in order to control and EQ without logarithmic pots, you'd need to get one with non-logarithmic pots, or just build your own.  They aren't that hard to build.

[Phorhas]

You know those amp and effect that can't give a flat EQ response (so they always add some definition to certain freaquencies? well
I want to know to get a round that - to build a tone stack that could be set to give the most natural and flat sound possible.

[aron]

You know those amp and effect that can't give a flat EQ response (so they always add some definition to certain freaquencies? well
I want to know to get a round that - to build a tone stack that could be set to give the most natural and flat sound possible.

Take a 5 band EQ, or something that has as many bands as you want.

Use a spectrum analyzer for every amp/pedal that you wish to "flatten out". Now replicate the EQ as fixed values when the knobs are turned all the way down by using fixed resistors inline with the pots.

There you go!

[The Tone God]

You know those amp and effect that can't give a flat EQ response (so they always add some definition to certain freaquencies? well
I want to know to get a round that - to build a tone stack that could be set to give the most natural and flat sound possible.

Silly question, why would you want to build an EQ that doesn't change the frequency response ? Wouldn't you just leave the EQ out if that is the case ? It might just be your wording but that question seems like saying "I want to build a distortion box that doesn't distorted the signal." Generally any effect you put in your signal chain will change the signal hence why its an effect.

If your asking about a tone stack to compensate exactly for the changing frequency response well thats alittle tougher. You have to look at what you are putting your signal chain and what each thing is doing to try to compensate for the change.

Andrew

[Nasse]

Hi-Fi guys use tone control bypass switch when they want absolutely shortest and straightest signal path. If potentiometers are too loose in tolerances you can use switches to select precision resistors and caps.

Even if you can make frequency responce straight, that does not mean that there is no different phase shifts at different frequencies or some exotic distortion you need be a professor to understand, and signal to noise ratio suffers mostly when signal goes trough eq. Have you tried Duncan Tone Stack Calculator? It draws a curve so you can see at which position your pots give flat response. Or they should :wink:

[downweverything]

Sorry to butt in, im prob completely wrong but what he asked for sounded like something I was looking for too.
I think what he was asking for was something like a boost only EQ.  When you turn all of the knobs fully counterclockwise you get no EQ.  Turning a particular knob clockwise give a boost at a specific frequency.  I tend to see these more in on bass active eqs because you usually only want a little more 40Hz or 3-4KHzish, this way it gives you more resolution and you dont have to worry about destroying the natural sound of a passive bass.  I cant answer the question of how to do it, but would be interested to know how.  Or if im completely in the wrong direction of what you want i apologize. just yell at me

[Mike Burgundy]

if that's what you want, you might want to borrow from a studio-style EQ with boost/cut, but use a half-the-original-value linear pot as a rheostat and a resistor of the same value. That way, with the pot at minimum it's half way as far as the circuit is concerned.
This only works if you can find a boost/cut schem using only one, linear, single pot.
Hm. Hold up, I might have a better idea:
Do a search on "pultec EQ" for ideas - the old pultecs had separate pots for boost and cut. Hardwire the cut part or leave it out if possible, replace the tube circuitry with, say, a minibooster and add a buffer in front: should do it.

[Nasse]

Oh I think have seen such thing somewhere, but it was somewhat opposite what you describe. It was in a guitar amp schem and there was that standard state variable filter (adjustable Q and center freq of course) circuit which give you lowpass, bandpass and highpass outputs and those were simply connected to mixing stage so that you could just dial each band as much as you like, and if all pots were full up, uou have straight response. Put reverse audio taper pots in that and thats it? Better or more hifi ready circuits and ready made units you can find in active loudspeaker crossover circuits. Mix those as you like.

[Phorhas]

First of all, Thanx all of you guys for answering and helping out.
BTW - mike I'm searching for the "pultec EQ" right now...

Well, just to ferther explain what I asked before.

I've played with amps that don't color your tone but rather give you the natural sound of your guitar with just a delicite (did I get that right?) touch of tubey-warmy-great ampy tone. Unlike some other amps which take your guitar and putout a differant beast altogether. maybe the question shoulden't concern EQs at all but rather other components or blocks of the FX/Amp anatomy...

Dan
:roll:

[Mike Burgundy]

keep in mind that an amp-plus-speakers that's *truly* not colouring your sound sounds like it actually *is* colouring - nasty and harsh, and thin.
What's percieved as "uncoloured" sound usually has some kind of low-end hump, a bit of a mid-dip and, really important, a high-frequency rolloff...
If you have this in the amp and guitarspeakers, the EQ idea will still be a good idea though.

[Phorhas]

Sweet

tnx

dan

[cd]

If you want to hear the "real" sound of a guitar, get/make a direct box, input it into your computer (or stereo) and listen through some good headphones.  As Mike B. says, what you'll hear will probably sound thin, buzzy, totally different from what you'd expect.  Amps are so variable that I tend to see the guitar + amp combination as a single instrument.  Come up with a good guitar + amp tone, then build on that... do you want that, only louder?  More mids/highs/bass? etc.  You start adding FX or EQ and have to tweak things using your ears.

Case in point: a friend of mine wanted a pedal that would boost the volume of his guitar without any EQ whatsoever.  He bought an expensive pedal that claimed to do just that, and for the most part, worked as advertised (I even put the circuit through a simulator and the EQ was pretty flat through the guitar's range, with minimal phase shifts.)  However, he was never satisfied with the pedal because the guitar may not have been EQd, but the increased volume sure made his amp sound different.  Not in a bad way, but not what he wanted either.