Mercury / Vario Boost

[cooder]

Mercury, compares to Catalinbread Vario Boost.
Built on Pedalpcb.com board, 1776 fx relay bypass, acrylicfaceplate over laser decal.
Excellent sounds out of this one, very useful and flexible boost circuit. Love it!









Brett Kingman can demo it much better than I can:

[Tremster]

You're building a pedal a day, an amazing amp and whatnot, all of it of professional quality. Do you find time to sleep?

[alanp]

Interesting, don't think I've seen this kind of "tune-able" boost before. Nicely executed -- the screwed in clear panel on top is becoming a signature mark!

I wonder why they used two TL072s, rather than one TL074...

[mrclean77]

So clean - keep em coming! I gotta check out this video, I'm also intrigued by the idea of a "tuneable" boost circuit.

[cooder]

Cheers guys!

You're building a pedal a day, an amazing amp and whatnot, all of it of professional quality. Do you find time to sleep?

Haha... no I'm not losing any sleep over this... and my bedtime has become way earlier than what it used to be. Nothing like a good few Zzzzzzzzzzzzzzzzzz....

So clean - keep em coming! I gotta check out this video, I'm also intrigued by the idea of a "tuneable" boost circuit.

Thanks Mrclean you must know about clean then...

Interesting, don't think I've seen this kind of "tune-able" boost before. Nicely executed -- the screwed in clear panel on top is becoming a signature mark!

I wonder why they used two TL072s, rather than one TL074...

Yes it's a great very flexible circuit, hard to understand why Catalinbread discontinued it. Probably just to change the line up and keep it fresh, maybe peeps didn't get the pedal? I think it's great.
Not sure about the two 072s versus 074... ask BuGG, he designed the pcb. I dunno what Catalinbread used originally.

[mrclean77]

Maybe it's my style of playing, but I think boosts are largely underrated/under-noticed. I'm sure there are a lot of TGP folks/etc who love boosts and have 4 different kinds on their boards, but 99% of my conversations, especially with local/younger players, regarding boosts all I get is crickets. Oh well. I was unfamiliar with this guy, need to do some homework.

[stringsthings]

... but I think boosts are largely underrated/under-noticed ...

+1

[dropanchor812]

Ooooo, didn't realize there was a pcb for this, gonna have to make it now!  Build looks great as always!

[cooder]

Quick update on this as I have incorporated in on my board and played with it awhile now: great sounds in there, very nice and versatile boost and tone shaper.
I did had a fairly strong switch popping which of course buggs me.
The pedalpcb circuit doesn't have any pull down resistor strangely. So i added a 1Mohm across input to ground which helped a lot but there was still a little bit. A second 1M ohm at output solved it all together, so if any of you guys build this as well and have some popping happen, this worked for me.

[jubal81]

Quick update on this as I have incorporated in on my board and played with it awhile now: great sounds in there, very nice and versatile boost and tone shaper.
I did had a fairly strong switch popping which of course buggs me.
The pedalpcb circuit doesn't have any pull down resistor strangely. So i added a 1Mohm across input to ground which helped a lot but there was still a little bit. A second 1M ohm at output solved it all together, so if any of you guys build this as well and have some popping happen, this worked for me.

Nice. Was just rereading the Mr. Black article on pop and he says a series resistor on the input helps, too, limiting any input rush current.

[cooder]

Nice. Was just rereading the Mr. Black article on pop and he says a series resistor on the input helps, too, limiting any input rush current.

Cheers Jason, what value of series resistor did he suggest?

[jubal81]

Nice. Was just rereading the Mr. Black article on pop and he says a series resistor on the input helps, too, limiting any input rush current.

Cheers Jason, what value of series resistor did he suggest?

Eh, he didn't specify. I'd reckon 1K would do it.
Here's a link to the article. Series resistor bit is near the end.https://www.mrblackpedals.com/blogs/straight-jive/6629778-what-really-causes-switch-pop

[cooder]

Nice. Was just rereading the Mr. Black article on pop and he says a series resistor on the input helps, too, limiting any input rush current.

Cheers Jason, what value of series resistor did he suggest?

Eh, he didn't specify. I'd reckon 1K would do it.
Here's a link to the article. Series resistor bit is near the end.https://www.mrblackpedals.com/blogs/straight-jive/6629778-what-really-causes-switch-pop

Thanks, that's and excellent and very entertaining read...!

[mjg]

So, if I understood the article, it means we don't actually need the input pull-down resistor on our boards, if we are using a switch that grounds the input when the effect is off?