Looking for boost only mid eq circuit

[maertz13]

Hello all, I’m looking to add a mod boost eq to the front of an existing circuit. I know the Clapton mid boost exists, but it is huge. Hoping for something op amp based. Just need to be able to switch in some mids to goose the front end. The zorkmid has this sort of boost, but the build doc isn’t out yet.

Thoughts?

 

[BuddytheReow]

Only boost and not cut?

 

[Feral Feline]

Peccary swears by the Mercurial Boost (and others advocate it vociferously, too).

Also check out the Pariah Mid Boost.
Maleficent Mids is another.
Then there's the Hyped Boost...

Maybe the XB-MB would work but is probably a lot bigger than you want if it's meant to be included in a single build with another circuit.
A tube-screamer type circuit without the clipping diodes...?
Just about any EQ pedal could do it, but the EQ Anyone? or other boost and then tailor the freq to your needs...

Zorkmid will have the parts-values printed on the board, so you wouldn't need the build-doc unless you need to do some trouble-shooting.

 

[maertz13]

Only boost and not cut?

yes, the original pedal is fairly scooped already

 

[maertz13]

Also check out the Pariah Mid Boost.

that is exactly the kind of quick and dirty solution i was looking for. i guess it's a modern take on the anderton schematic i saw but it didn't look complete. this with a fixed volume and a DPDT bypass switch will be perfect

 

[HamishR]

The BB-MB does have a significant mid-bump but the "mid-boost" isn't really a mid boost. The BB is a TS with the stock tone control preset and a two-way EQ added. The BB-MB is exactly the same but with the stock tone control reinstated. So not really a mid boost at all - quite confusing.

There are loads of simple pedals which boost mids and gain. The Tchula can be used as a mid-boost if you leave off the diodes and add a master volume - very easily done. The Red Rooster is called a Treble Booster but is really more of a mid-boost. The name is deceptive. It doesn't really boost treble as much as a lovely mid bump. You can hear where the TS came from - it's almost a successor to the Treble Booster.

 

[Alan W]

The Mercurial’s ability to select the boosted frequency is really useful—the other circuits mentioned may also have this; I’m not familiar with them.

 

[aquataur]

freqboost
There is a schematic on the web from muzique.com that is indeed incomplete. It shows only the principle.
You find a complete working pedal in C.A.'s book "Electronic Projects for Musicians", project # 10.
The complete pdf is on the web, you have to poke a little...

 

[spi]

Mecurial was my first thought. Maybe Tone Job as another option.

 

[jcpst]

The mercurial is great. I have thought replacing the frequency pot with a reverse taper, I still think it’s weird to go from hi freq to low when turning CW.

 

[Feral Feline]

The mercurial is great. I have thought replacing the frequency pot with a reverse taper, I still think it’s weird to go from hi freq to low when turning CW.

I had so many builds where I was going to use a reverse taper pot to have the rotation of something the way I wanted while still having the pot board-mounted... and then I read RG Keen's The Secret Life of Pots and discovered the only way to accomplish what I wanted was to offboard-wire the pots, which defeated the purpose of having the pots board-mounted and holding the board in place and ... *sigh*.

For a control that gets bassier the more you turn it clockwise, to reverse it — bass CCW to treble CW — normally you'd want to swap out the outer-leg wiring (3 to 1 and 1 to 3 for a voltage divider) — not sure how that'd work in the Mercurial what with one gang of the dual-gang pot being wired as a rheostat while the other is wired as a voltage divider.

 

[peccary]

Everyone needs a Mercurial Boost.

 

[jcpst]

I had so many builds where I was going to use a reverse taper pot to have the rotation of something the way I wanted while still having the pot board-mounted...

If I’m being honest with myself, I’d rather just live with it. It can only be turned in two directions, after all. Much easier to just turn it the other way than modify it.

 

[Feral Feline]

If I’m being honest with myself, I’d rather just live with it. It can only be turned in two directions, after all. Much easier to just turn it the other way than modify it.

I think of it as a bass control, so the more bass wanted (and I want it all, all yer bass are belong to us), turn it up CW...

I don't like where the knob is on the Dielectric, for instance... (Tchula) board, so I'm going to mount all components on the back side of the board, flip it over so I can have the knob in the exact centre of the pedal while still turnin' the correct way and s'portin' the PCB — then I'm going to stick the second stomper up between the jacks; might have some rails bolted to the pedal to protect the knob from all the stompin on the stomperswitches... Two stompers in a portrait-oriented 1590N1 are usually too close together, so instead top and bottom something like this:

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Rails like those used by Effectrode to protect the tubes: