frequencies in guitar

Ok, you got your soldering iron and nothing is going to hold you back, but you have no clue where to start or what to build. There were others before you with the same questions... read them first.
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copachino
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Post by copachino »

hi, i was thinking about freq in guitar but im not sure about i, i mean for example highs, mid or bass, if i ant to set a filter for each freq, what would be the setting freq of each???

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Duckman
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Post by Duckman »

Check this :thumbsup
http://dpaudioa.blogspot.mx/2011/02/fre ... nd-eq.html
You have a lot of range to cover in a guitar.
Why not start analyzing any standard EQ pedal, like the Boss GE-7 or something similar from Ibanez or MXR?

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oldrenegade
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Post by oldrenegade »

Have a look at some equaliser schematics. See list at left bottom of pic
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electro harmonix graphic eq.jpg

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phatt
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Post by phatt »

Just work out what frequencies the guitar covers (See the coloured graph on the link Duckman posted) :thumbsup

Every octave is a doubling of Freq,,So

Tenor guitar;
Bottom E string is 82Hz
4th String second Fret =164
Open top E string =328
12th fret =656
24th fret =1312
---------------
From there up is harmonics;
2624Hz and 5248Hz.

Past that is likely to hinder the chase for mojo tone. :secret:

caveat;
If all you do is strum a few chords on a clean guitar then bandwidth won't matter much
BUT once you introduce light too hard driven distortion then limiting bandwidth is VITAL to success. Distortion is easy to make happen the magic is in the tone shaping and that is the hard part to nail down.

IME, the magic points are notch cut around 400Hz and then again somewhere between 700 < 1kHz.
That in either separate or combination will cover most of the classic rock sounds.

Metal you can boost the bottom end as well as a mild scoop.

If you want the midrange honk then invert the 400Hz and the 700Hz. Don't boost above ~1500Hz as it will get brittle fast and destroy the sweetness.

There is no Exacts as all this is highly dependent on a multitude of variables from pickups to speakers used and dozens of places in the Amplification circuits used.

I've spent hours fine tuning the magic smoke of circuits I've built and just when I've found the magic.
Well I take to the gig and it sounds like crap.

the environment (Room acoustics) also plays a big role in the end result. :scratch :hmmm:
Phil.

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copachino
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Post by copachino »

phatt wrote:Just work out what frequencies the guitar covers (See the coloured graph on the link Duckman posted) :thumbsup

Every octave is a doubling of Freq,,So

Tenor guitar;
Bottom E string is 82Hz
4th String second Fret =164
Open top E string =328
12th fret =656
24th fret =1312
---------------
From there up is harmonics;
2624Hz and 5248Hz.

Past that is likely to hinder the chase for mojo tone. :secret:

caveat;
If all you do is strum a few chords on a clean guitar then bandwidth won't matter much
BUT once you introduce light too hard driven distortion then limiting bandwidth is VITAL to success. Distortion is easy to make happen the magic is in the tone shaping and that is the hard part to nail down.

IME, the magic points are notch cut around 400Hz and then again somewhere between 700 < 1kHz.
That in either separate or combination will cover most of the classic rock sounds.

Metal you can boost the bottom end as well as a mild scoop.

If you want the midrange honk then invert the 400Hz and the 700Hz. Don't boost above ~1500Hz as it will get brittle fast and destroy the sweetness.

There is no Exacts as all this is highly dependent on a multitude of variables from pickups to speakers used and dozens of places in the Amplification circuits used.

I've spent hours fine tuning the magic smoke of circuits I've built and just when I've found the magic.
Well I take to the gig and it sounds like crap.

the environment (Room acoustics) also plays a big role in the end result. :scratch :hmmm:
Phil.


i guess ill have to set the filters that i want to for example a notch, or a band pass and stuff like that and then just adjust values to hear

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phatt
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Post by phatt »

Hey , your catching on fast :thumbsup

Remember tone shaping is cumulative. :scratch:
You have to tune the whole system tone so in one place you might need a lot of bass cut while another section you may need to leave flat then another cut before poweramp to get the desired effect.

And that can be very tricky to pull off.

A simple simulation of some of the classic Valve Amps shows the above observation.
In most cases the better sounding rigs had treble roll off as well as bass roll off especially inside the power stage. Add limited bandwidth OT's and bingo they sounded great.
Sadly SS power stages in general run a flatter response so you have to take that into account in the preamp sections. (use notching and cab sims for example)

Some of those fender SS rigs use a hi pass filter right at the input yet the bass tends to flab out on the models I've worked on.
Maybe the designer thought that once you cut the bass it matters little after that.
Obviously that was nowhere near enough lol.

You have to keep cutting bass in other places in the signal chain otherwise you can render a good tone shaping idea useless.

Most folks think the tone controls are the important part for tone which is Understandable but it's far from the truth. :secret:
They are just there for fine adjustment,, the real tone is dependent on how well you design the whole system tone.

An old wise teck once stated that to build an audio amplifier you need to start at the speaker and work back,, having spent 30~ something years trying to get my head around it all I now see wisdom in his approach.
Classic Valve Amps were AC coupled (cap isolation between stages) but opamps and their high current relatives (poweramps) are DC coupled so you have to work in a very different manner.

Today the player is continually frustrated because the basic concept has been lost too 20/20 bandwidth tiny harsh noise making crap Amplifiers.
Some of the greatest electric guitar sounds ever recorded where likely done on very basic and bandwidth challenged equipment.

If you want the classic sounds get away from wide bandwidth equipment.
They only use high SPL speakers because they *KNOW the kids* off today will buy the loudest amp rig in the shop.
Phil.

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