Mercurial Boost (Catlinbread Varioboost)

MichaelW

Well-known member
Build Rating
5.00 star(s)
I can’t recall what or who inspired me to buy this board but i’ve been sitting on it for quite some time. Rather uncharacteristic of me being the “boost freak” that I am….haha.

Was chatting with my Chief Enabler @szukalski and we’ve been talking about the Modus Operandi boost. We’re both huge fans of this boost (actually @szukalski was the one that turned me into it). Hard to put into words why it sounds so good. Might be the eq, or the “faux compression” like effect it has but it makes any overdrive just sound better to me. Anyway, the discussion has been around what boost out there would knock the Modus off the board. So I asked if he had built the Varioboost yet. To which his prompt reply was to whip it up on a breadboard. (I look forward to the day when I get around to learning how to do that, just too much going on right now with builds heh….waiting for a break in the action….). Anyway, he was pretty glowing with his results and opined that this might be “the one” that could finally top the modus, so of course I had to build it!

Super straightforward and easy build. Low component count, perfect for a “just before dinner” build. I had drilled a bunch of enclosures and painted them yesterday so it all went together pretty quickly,. I was just starting to mess with it when I got the call for dinner then got busy afterwards and never got back to it. But what I did hear sounded really promising. I really like the notion of being able to dial up the frequency you want to boost but it’s not an EQ per se. It’s not as precise as that for tone shaping but rather the frequency knob seems to change the characterof the boost. So in a sense it’s many boosts in one. Still figuring out how to use it, i think i need to go look up the manual. I‘m not quite sure what the 12db knob does exactly, but will definitely be playing with it more tomorrow.

I painted this one a flat gray then put a coat of satin gloss over it for easier handling. Not completely sure I like this satin gloss paint, seems to leave a bit of milkiness to the color. But it could also be from uneven spraying technique.

I’m building up a pretty healthy collection of rattle can paints and the experimentation continues,

Oh and if you look closely you can see an extra center punch mark, which was where the drill template located the led. I noticed how far off it was from the led pads on the board before drilling and decided to relocate the led. Initially the color coats of gray paint filled the hole but once it dried it reappeared. But I think i can live with it.

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I can’t recall what or who inspired me to buy this board but i’ve been sitting on it for quite some time. Rather uncharacteristic of me being the “boost freak” that I am….haha.

Was chatting with my Chief Enabler @szukalski and we’ve been talking about the Modus Operandi boost. We’re both huge fans of this boost (actually @szukalski was the one that turned me into it). Hard to put into words why it sounds so good. Might be the eq, or the “faux compression” like effect it has but it maks any overdrive just sound better to me. Anyway, the discussion has been around what boost out there would knock the Modus off the board. So I asked if he had built the Varioboost yet. To which his prompt reply was to whip it up on a breadboard. (I look forward to the day when I get around to learning how to do that, just too much going on right now with builds heh….waiting for a break in the action….). Anyway, he was pretty glowing with his results and opined that this might be “the one” that could finally top the modus, so of course I had to build it!

Super straightforward and easy build. Low component count, perfect for a “just before dinner” build. I had drilled a bunch of enclosures and painted them yesterday so it all went together pretty quickly,. I was just starting to mess with it when I got the call for dinner then got busy afterwards and never got back to it. But what I did hear sounded really promising. I really like the notion of being able to dial up the frequency you want to boost but it’s not an EQ per se. It’s not as precise as that for tone shaping but rather the frequency knob seems to change the characterof the boost. So in a sense it’s many boosts in one. Still figuring out how to use it, i think i need to go look up the manual. I‘m not quite sure what the 12db knob does exactly, but will definitely be playing with it more tomorrow.

I painted this one a flat gray then put a coat of satin gloss over it for easier handling. Not completely sure I like this satin gloss paint, seems to leave a bit of milkiness to the color. But it could also be from uneven spraying technique.

I’m building up a pretty healthy collection of rattle can paints and the experimentation continues,

Oh and if you look closely you can see an extra center punch mark, which was where the drill template located the led. I noticed how far off it was from the led pads on the board before drilling and decided to relocate the led. Initially the color coats of gray paint filled the hole but once it dried it reappeared. But I think i can live with it.

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I own an Original & I also built this, It's a Great little Boost to fine tune your Pickups!
Here is Brettt Kingman who was the agent for Catalinbread at the time in Australia:
 
Lovely build!

Like @music6000 said, perfect for tuning your pickups or a stack. With an amp on edge of breakup, it’s great. (Jumpered Jtm45 and the varioboost settles a lot of wishes).

I see this in my top three boosts:
Mercurial - flexible opamp boost w/ frequency control. Has that opamp hi-mid presence.
Modus - great Si transistor boost. Has the BJT attributes, a “blanket” on your tone.
Chickenhead- great Ge transistor boost. Adds a bit of noise to your signal.

I like having all three on hand when stacking. The methods of boost add their own flavour, and interact with the other pedals differently. My ears don’t like stacking the same type, I.e. opamp boost into opamp overdrive, it accentuates their attributes too much.

Waiting on the Chickenhead build next. Maybe @Robert comes up with a new revision for PNP Ge? :)
 
I wish this dang pedal fit the normal 3 knob layout. I assume the double gang pot is too big?
Not sure what you mean. It IS a standard 3 knob layout......just upside down :ROFLMAO: .

I think @Robert was just following how the original retail pedal was laid out with the freq knob in the middle. The dual gang pot would fit in any of the 3 positions just fine like any other board that uses a dual gang. (Although you'd probably want to hack some kind of pot cover.)
 
So I played around with it some more this morning, definitely a very cool boost and sounds great but it's not "idiot proof".
You have the flexibility to hone in on boosting certain frequencies. I also read an old thread where @Chuck D. Bones was saying that the 12db knob acts almost like a Q control, that helps me a lot in understanding how to use it. All 3 knobs are highly interactive and there's a lot of flexibility in how to use this boost. Definitely a "thinking man's boost"......(which begs the question...why did "I" build it hahahaha)

I am not getting the notion that Brett Kingman was talking about "making a Strat sound like a Les Paul and vice versa". Not that I would ever want to do that but my singles still sound like singles and HB's still sound like HB's.
 
Peccary is so effective in his championing this circuit that I bought the PCB, and then discovered I already had it.

So I'll build one for me and the secondf for my friend.


Then I'll have to buy the 4-knob version that's pending. Why? I don't know... I collect PCBs, just in case the apocalypse comes and I run out of drink coasters.

Yep, it's a bit more complex than the Mercurial.

So what is this new 4-knob "Mercurial"?

Will it get a new name?

If so, how 'bout "Crazy 'Bout A Mercury"?
Or maybe sticking with messenger of the gods etc: "HERMES"

Or the following in bold could be the new name:
from Latin mercuriālis, of the god or planet Mercury, from Mercurius, Mercury. ... Stella Mercuriī Star of Mercury
OR
"More Curious"
or...
"Marie Currie"


I don't know, but the name should somehow pay TRIBUTE to the original Mercurial...

...some sort of Homage or Acclamation; perhaps Paean, Panegyric or even Encomium, but not Eulogium.
Possibly @peccary could be put in charge for naming it, given his extensive virtue-extolling and giving LAUDATION of/to the original Mercurial.
 
For those of you that have built and used this - what overdrives have you tried stacking with?

I haven’t built this yet, but I’m thinking this with a flexible OD could be the magical “find my tone with any guitar and amp” pedal I’ve always wanted. In particular, I’m thinking maybe a Tommy (Timmy) would be a particularly great pairing, given the Tommy’s flat response and flexible bass and treble controls. Perhaps even the Tim with its effects loop might be a good place for the Mercurial…

Currently I’m liking the Ember Boost (TCE Spark Booster) for this Swiss army role, and I like it, but I feel like a pairing of this Mercurial Boost might give even more flexibility…
 
For those of you that have built and used this - what overdrives have you tried stacking with?

I haven’t built this yet, but I’m thinking this with a flexible OD could be the magical “find my tone with any guitar and amp” pedal I’ve always wanted. In particular, I’m thinking maybe a Tommy (Timmy) would be a particularly great pairing, given the Tommy’s flat response and flexible bass and treble controls. Perhaps even the Tim with its effects loop might be a good place for the Mercurial…

Currently I’m liking the Ember Boost (TCE Spark Booster) for this Swiss army role, and I like it, but I feel like a pairing of this Mercurial Boost might give even more flexibility…
The Mercurial definitely has a lot more oomph than the Ember/Spark. I look at the Ember as more of a tone shaper as opposed to a "boost" per se. The VarioBoost is not as intuitive to use as the the more standard tone stack of the Ember but you can dial in and boost specific frequencies to shape your tone. I've played with it boosting my Green Russian Muffin, DOD250, 5lb Bag of Gold, Grover Drive, Tellurian Drive. Chauffer, Cattle Driver and Finale Overdrive (just because they happen to all be still sitting in my pedal chain on my desk at the moment) :) I'm sure it would work just as well with anything else I have on the shelf. Not that all of those drives NEED to the Mercurial, just saying I've played around with boosting them to see how the Mercurial works. Pretty cool boost for sure. I don't see it leaving my board anytime soon.
 
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