Been playing with EQs over the past couple weeks...

[skreddy]

First I wanted to make an exact duplicate of my Hiwatt's tone stack (well I didn't bother with the Presence control, just wanted a quick listen of how its 3 regular bands would work in a stompbox format). Good news: it works. Bad news: way too lossy. Then adding a gain-makeup stage after brings up a massive noise floor. So that's out.

So I went to an active 3-band tone stack. I also designed a really cool pre-gain stage (instead of just a buffer at the input) that features soft, ever-so-slightly-gritty germanium-diode compression as you turn it up (not unlike the sound of a Klon in cleanish-boost mode). Good news: it works great! No loss, obviously. Noise level is fine, can do a flat response with all controls at noon, can boost or cut all 3 bands no problem. Only minor issue: after playing with it, I got frustrated with the lack of ability to fine-tune and target specific midrange bands. It's more of a "sledge hammer" approach to tone control. Works super great but not particularly good for precision or elegance. You can stay flat, add a bit of compression, do a very honky midrange hump, or a doomy mid scoop, etc., etc.

So now I want to make a new version where I can have 3 separate midrange bands, parametric, each with freq, Q-factor, and boost/cut. Plus bass and treble, each with 3 selectable shelving freqs. Have not proto'd this version yet, but I will soon.

Now I'm thinking, why not both? Why not make a 3-band version and a 5-band parametric version too? I already have names picked out for both...

[ak47]

Hiwatt tone stacks are my favorite by far each control works so well.. especially if you like using pedals.. yes, I loooove my Hiwatts!!

So of course you now have my full attention Marc A question on placement.. what is your take on a 5 band parametric pre dirt and 3 band passive post dirt setup?

[skreddy]

Hiwatt tone stacks are my favorite by far each control works so well.. especially if you like using pedals.. yes, I loooove my Hiwatts!!

So of course you now have my full attention Marc A question on placement.. what is your take on a 5 band parametric pre dirt and 3 band passive post dirt setup?

Well, my initial idea was to actually put gain stages, each with a different sort of available distortion, on both sides of the tone stack. I already did design that nice mostly-clean pre-gain stage, and it should really please folks who like the Klon's cleanish boost sound. And I was going to make something more along the lines of a power-amp distortion to go after, something that will get that certain amp-on-the-verge-of-meltdown, juicy but filthy compression, on the back end.

But now after seeing how much will go into the 5-band parametric version, I'm thinking of making it all clean so it will go ANYWHERE in the chain, before, after, or in-between dirt stages.

(oh, the 3-band isn't going to be passive; it's all active. Passive was too lossy and would introduce an unacceptable noise floor after bringing the volume back up)

[ak47]

Ok. Cool.. I like the sound of both ideas actually one thing that I have always thought about is that a lot of people boost & cut frequencies a bit too far when using eq's with guitar.. just me perhaps; but to get a tasty curve through the right frequencies without it sounding too notched or honky can be quite a challenge. I don't know how this would affect design though because it is a matter of balancing the ability to offer a wide range of control on different bandwidths against keeping it sounding natural in extreme settings.. does this make any sense? Running an eq that doesn't sound overly eq'd?

[skreddy]

Ok. Cool.. I like the sound of both ideas actually one thing that I have always thought about is that a lot of people boost & cut frequencies a bit too far when using eq's with guitar.. just me perhaps; but to get a tasty curve through the right frequencies without it sounding too notched or honky can be quite a challenge. I don't know how this would affect design though because it is a matter of balancing the ability to offer a wide range of control on different bandwidths against keeping it sounding natural in extreme settings.. does this make any sense? Running an eq that doesn't sound overly eq'd?

Well, job one is to make it sound good. I do like to dial out unpleasantries too, so that even extreme knob settings won't sound like garbage. But on this deluxe 5-band thingie, I can't guarantee that a user still can't make it sound overly eq'd. Just the nature of giving so much power and so many knobs. But I totally get what you mean.

A lot of folks have been interested in the Frank Zappa thing, where he gets those crazy mids, and a lot of folks like the cocked wah thing, and then there is the whole deal of just wanting something a little bit tweaked. Usually we builders will design the whole eq into a pedal, you know? But we have no way of predicting what sort of room or hall or stadium, indoors or outdoors, you might be playing; and every situation comes with its own set of unique eq requirements. Not to mention the whole recording studio thing, where you don't necessarily want an open, full-spectrum eq but something that sits well in its own place in the mix. And overdubs might want to sound a little different from each other, etc., etc.

So the multi-band parametric would likely not be for everybody, only the truly dedicated knob twiddlers, and of course a two-edged sword--with all that power comes the ability to make horrible choices!

Edit: I will spend a little bit more time tuning the bands of my 3-band version, though.

[ak47]

So the multi-band parametric would likely not be for everybody, only the truly dedicated knob twiddlers, and of course a two-edged sword--with all that power comes the ability to make horrible choices!

Exactly!! This is giving me a 'Lord of the Rings' vibe Bring it on!

Of course it is all about the sound as you point out.. finding that inspired tone that gets the creativity flowing is what it is all about

[skreddy]

So the multi-band parametric would likely not be for everybody, only the truly dedicated knob twiddlers, and of course a two-edged sword--with all that power comes the ability to make horrible choices!

Exactly!! This is giving me a 'Lord of the Rings' vibe Bring it on!

Of course it is all about the sound as you point out.. finding that inspired tone that gets the creativity flowing is what it is all about

Oh crap; so I really got into the zone yesterday tweaking those freqs on my 3-band eq. Started to sound nice, so I abandoned the concept of giving it a dirty boost at the input (instead I'm just giving it a "clean, graceful overload" compression ability at high gain levels rather than allowing the op-amp to hit the limits of its supply rails) and upgraded the op-amp to a hi-fi Burr Brown. OMG, it's definitely not frustrating to play with now. I haven't abandoned the 5-band idea, but I'm all in on the 3-band concept, and it sounds great. Will almost certainly fit into a small enclosure, too, unless I do something extravagant like adding loop(s) to it (you know, for piggy-backing other things like OD/dist so one switch turns on multiple things all eq'd at the same time). But I already have a separate product, the Dual Loop, that's designed for just that, so why incorporate that into another pedal that could be compact instead?

[ak47]

You know it must be good when the designer is this happy..