Tone section before clipping section in an distortion peda

[RandomRedLetters]

If the signal is eq'ed before going into a distortion pedal and sounds better to alot of guitarists (eq really shapes distortion aparently), wouldnt an improved design have the tone stack before the clipping section?

Anyone build a pedal that has that? Any thoughts on it?

[aron]

Yes. Years ago, I mean years ago, R.G. advocated a 5 band before and 5 band after a distortion pedal.

Of course this works, but what many found was that the amount of bass (lack of it actually) and hi frequency roll off were the two main factors that affected the tone going into a distortion pedal so the input cap and high frequency roll off caps can do the job and can be highly tailored to your guitar.

You still need the tone stack after the distortion if you want control over the disortion tone post clipping.

[JHS]

The first IBZ OD-2s have a pre-distortion EQ. The result is a very artificial, pinched distortion, and IBZ dropped the pre- tonecontrol after a short time and put the EQ after the clippingstage.

Some FX-Boxes have a small RC-network in front of the clippingstage for pre-shaping the tone or boosting mids (OD3, BD-2, it looks like they want to emulate that overdriven blackface sound).

Personally, I prefer cutting bass and increasing highs before a clipping stage and boosting the bass and reducing the highs after the clipper to taste, this helps to prevent muddy distortion especially in highgain drives (nowadays I prefer cascaded or parallel clipping stages in those drives).

If I add a tonecontrol, it's always sticked after the distortion,  I think that's the place where it's most effective.
Depending on the distortion structure of the drive, a tuned BM or RAT-style tonecontrol  is all I need so far for finetuning the sound.

JHS

[aron]

Yes, good post. The tone controls work much better with all of those harmonics to work with.

The pre-tone controls (ala Fender etc...) can work but obviously they have more affect on the tone before heavy clipping occurs.

[petemoore]

A cap added in series with the clipping diodes [for bass non distortion] and one across the diodes [for cliping / HF rolloff] may be used.

[RandomRedLetters]

So for something like a single stage overdrive, it might be good to have a tone stack on each end, but pre-eq before a really high gain clipping section may basically be useless? At least thats how Im understanding this.

[aron]

I don't know if I would say useless, but it would have diminishing returns once the distortion is above a certain level.

Of course with DIY, you can do anything even it if costs too much and might not be that effective.

[Mark Hammer]

I had a thread back in July about a modified Tube Sound Fuzz I called the Forty-Niner.  I built one of the Anderton Frequency Boosters into it just ahead of the CMOS invertors and stuck a SWTC (Stupidly Wonderful Tone Control) after the invertors.  This provided for modest pre-emphasis and modest post-distortion EQ.  It doesn't take a whole lot of before anf after stuff to yield some nice sounds.  I have a sound sample with the zipfile (hammer.ampage.org) that may or may not illustrate this effectively.

The rule to remember is that distortions run out of headroom sooner for those parts of the signal closer to clipping threshold, and add harmonic content based on what you feed them.  The pre-EQ/post-EQ arrangement allows you to determine what harmonics are generally being added, and what portion of that you wish to keep.

[WGTP]

I usually maximise the bass after the clipping stages and reduce it at input for smoothness without loosing too much at the output.