EQ Anyone?

Nic

Well-known member
Build went really well, sat on the workbench for some months before I finally ordered an enclosure then another couple months to finish the wiring.

It does what it does. I find it cuts a lot of volume but that may be how it works.

Here it is, simple design, 1590B cream color with brown accents.

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Hey, neat build!
Your electro caps soldered to the rear, just an aesthetic choice? It looks super tidy.
 
Hey, neat build!
Your electro caps soldered to the rear, just an aesthetic choice? It looks super tidy.
I was not sure how I would mount the board at first and those were kind of tall. They fit well around the pots.
 
Nice, clean build! Can you compare this to a Mercurial Boost? Better? Worse? Same?
I wasn't familiar with the NE-1, so I just did a bit of research to confirm my guess. Short answer—no, they do different things (although the Mercurial might be able to closely imitate what the NE-1 does. Mercurial is a boost, with a tunable notch filter. You pick a center frequency, and then you can boost it, or reduce it, and then it gets blended with the original signal and both get output through a gain stage that can also allow it to be a boost. (One of my most favorite sounding IC based boosts.)

The NE-1 takes that center frequency you select, and then applies a notch filter to it, of tunable Q. I'm not sure if the level control is for output, or for how much of the effect is mixed with the original signal (I had assumed the former, but their description makes me think the latter. Plus @Nic saying that its cuts volume—which makes sense, since the filter is subtractive). I'm guessing the higher you turn the level the lower the output gets—does that track with your experience, @Nic?

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EDIT: I looked more carefully at their charts, and hadn't noticed the dashed line before, so those graphs do imply that it can add gain also.
 
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It's funny, because of the design I figured it was based on a Boss pedal, and then saw that the NE-7 was the Boss 7 band. And I've been out of the pedal building hobby for a while (just taking a break!) I didn't realize that the post title was the PCB name—Boy, Robert has BEEN BUSY!

And. as several others have said, really nice clean work.
 
I'm guessing the higher you turn the level the lower the output gets—does that track with your experience, @Nic?
I will have to play with it a little more. I really think level work intuitively, so CW for higher output, it's just that unity is really high, I'll really have to confirm the interaction between the knobs and switch.
 
Reminds me of @Passinwind preamp.
I actually have a different EQ pedal in design that combines a one band PEQ and a variable HPF, using a 9V—> +/- 15V Traco power converter chip. It has plenty of headroom to drive any power amp directly and my primary projected use case is FRFR powered speakers. I hope to add it to my open source GitHub repository sooner than later.
 
I actually have a different EQ pedal in design that combines a one band PEQ and a variable HPF, using a 9V—> +/- 15V Traco power converter chip. It has plenty of headroom to drive any power amp directly and my primary projected use case is FRFR powered speakers. I hope to add it to my open source GitHub repository sooner than later.
You had a design where the resonant LPF was used like a tone control yeah. Kind of an alembic deal?

That's what I was thinking of when I brought it up.
 
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